JP2002016638A - Routing information retrieving device and computer readable recording medium having routing information retrieval control data recorded thereon - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a routing information retrieving device capable of shortening the time taken to perform setting and setting changing and reducing the loads on setting, setting changing and cost. SOLUTION: Each address control table includes the pointers of lower order address control tables when all combined pieces of address information obtained by combining pieces of divided address information from its own divided address information up to the highest order divided address information coincide with the higher order part of any of pieces of higher order divided address information in each piece of divided address information of its own hierarchy, and includes routing information table pointers that correspond to higher order divided address information when information obtained by abandoning part of the divided address information from all of the combined pieces of address information or from the lowest order part of the combined pieces of address information coincides with all of any higher order divided address information.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a routing information search apparatus used for searching routing information (information indicating a packet transmission port) in a communication network device such as a relay device or a terminal device connected to a communication network. The present invention relates to a computer-readable recording medium on which routing information search control data is recorded, and more particularly, to a routing information search device and a routing information search control data for quickly searching for a routing information (address search) corresponding to a longest match of an address mask. The present invention relates to a recorded computer-readable recording medium.

[0002]

2. Description of the Related Art In communication between terminal devices in a communication network, an address for identifying a communication partner terminal device is used. A communication network device such as a relay device or a terminal device connected to the communication network performs processing such as determination of a transmission interface for transmitting the packet based on a destination address of the packet to be processed.
Specifically, the communication network device holds routing information for determining a transmission interface, searches for routing information based on destination address information of a packet to be processed, and obtains the routing information. The packet is transmitted by the transmission interface indicated in the routing information.

The routing information is associated with information obtained by multiplying address information (address information) by an address mask (hereinafter referred to as upper address information). here,
The address mask masks (hides) a predetermined number of lower bits of the address information. By multiplying the address information by the address mask, only a predetermined number of upper bits of the address information become valid.

That is, the upper address information is information of a predetermined number of upper bits of the address information, and indicates an address group in which the predetermined number of upper bits match. By holding the routing information in association with the upper address information, the amount of information to be held can be reduced as compared with the case where the routing information is held in association with each address information. Note that the number of bits to be masked can be set to “0”. In this case, the address information and the upper address information correspond one-to-one.

Here, there are cases where the address mask and the upper address information have a plurality of bit lengths. In such a case, even if the result of multiplying certain address information by a certain address mask matches certain upper address information, the result of multiplying that address information by another address mask matches the other address mask May be. That is, the result of multiplying one piece of address information by a plurality of address masks having different bit lengths may coincide with a plurality of upper address information having different bit lengths.

As a method of determining higher-level address information in such a case, "longest match of address mask" is known. In the longest match of the address mask, when a result obtained by multiplying one address information by a plurality of address masks having different bit lengths matches a plurality of upper address information having different bit lengths, among the upper address information, The upper address information having the longest unmasked bit length is set as upper address information corresponding to the address information. In a communication network device,
There is a demand for a process of searching for routing information corresponding to the longest match of the address mask at a high speed, to reduce a delay time due to this process, and to improve a throughput.

By the way, as a conventional routing information search method corresponding to the longest match of the address mask,
For example, a "network address search method" disclosed in Japanese Patent Application Laid-Open No. Hei 10-257066 is known.
In this network address search method, routing information is searched by using a plurality of hierarchically configured address control tables corresponding to divided address information obtained by hierarchically dividing address information by a predetermined number of bits. here,
The division of the address information is performed according to the bit length of the upper address information. The division address information is used as an index.

FIG. 19 is a diagram showing a configuration of an address control table used in the network address search method. Here, an example is shown in which a 32-bit IP address is used as an address, and a 4-layer address control table is configured to correspond to the divided address information obtained by dividing this address information into four every eight bits. This address control table stores the first divided address information corresponding to the uppermost divided address information.
An address control table 91, a second address control table 92 corresponding to the second divided address information, a third address control table 93 corresponding to the third divided address information, and a third address control table 93 corresponding to the fourth divided address information. 4 address control table 94.

The first address control table 91 is used for search processing based on the highest division address information (highest 8 bits) of the destination address of a packet.
Information 912 indicating whether to continue or end the search, at the positions indicated by pointers A000 to A255 corresponding to the most significant division address information of 255 (decimal number).
When the search is continued, a next table pointer 913 indicating a lower address control table to be referred to next (address control table used for search processing based on lower divided address information), and a packet is transmitted when the search ends. And information 914 indicating the transmission interface to be used.

Similarly, the second address control table 92
Is used for a search process based on the second divided address information (9th to 16th bits) of the destination address of the packet, and corresponds to the second divided address information from 0 to 255 (decimal number). Pointers B000 to B2
At the position indicated by 55, information 922 indicating whether to continue or end the search, a next table pointer 923 indicating the lower address control table to be referred next when the search is continued, and an end of the search In this case, information 924 indicating the transmission interface for transmitting the packet is recorded.

Similarly, the third address control table 93
Is used for a search process using the third divided address information (17th to 24th bits) of the destination address of the packet, and corresponds to the third divided address information from 0 to 255 (decimal number). Pointers C000-C
At the position indicated by 255, information 932 indicating whether to continue or end the search, and when the search is to be continued,
Next table pointer 933 indicating the lower address control table to be referred to next, and information 934 indicating the transmission interface for transmitting the packet when the search is completed.
Is recorded.

Similarly, the fourth address control table 94
Is used for a search process based on the fourth divided address information (25th to 32nd bits) of the destination address of the packet, and corresponds to the fourth divided address information from 0 to 255 (decimal number). Pointer area D000
To the position indicated by D255, the information 942 indicating whether to continue or end the search, the next table pointer 943 indicating the lower address control table to be referred next when the search is continued, and the search To end,
Information 9 indicating a transmission interface for transmitting a packet
44 are recorded.

Information indicating whether the search of each address control table is continued or terminated (hereinafter, referred to as a search end / continuation flag) 912, 922, 923, 942 is "0" when indicating the end of the search; When indicating continuation, the value is “1”. When the search end / continuation flag is “0”, a transmission interface name for transmitting a packet is set as information indicating the transmission interface corresponding to the search end / continuation flag. On the other hand, when the search end / continuation flag is “1”, a pointer indicating the next lower address search table to be referred to next is set as the next table pointer corresponding to the search end / continuation flag. Either the information indicating the transmission interface or the next table pointer is set for one piece of divided address information, and neither of them is set.

Uppermost first address control table 91
Is only one block from A000 to A255, but there may be a plurality of blocks in the lower address control table corresponding to different upper division address information. For example, if the search is continued when the highest-order division address information is “133” and “134”, the second second address control table 92 stores the highest-order division address information “133”, “134”. Are provided in two blocks. Also, the fourth address control table 94
Is the lowest address control table, all the search end / continuation flags 942 indicate “0” indicating the search end.
And all the next table pointers 943 are in an unset state.

In the following description, the upper address information and the address mask are divided for every 8 bits, and the numbers are separated by dots and represented by decimal numbers. The address mask has the same length as the address information, and validates the address information corresponding to the bit where a binary "1" stands. For example, the address mask “255.0.
0.0 "is represented as" 11111111.00 "in binary.
0000000000000000000000000 "
And the upper 8 bits of the address information are made valid.

In the example of FIG. 19, the address is an address mask "255.0.0.0" and the upper address information "13
In the case of "3.", the transmission interface B is selected, and the address is set to the address mask "255.255.25".
5.255 ", upper address information" 133.141.7 "
7.59 ”, the transmission interface C
, And the address control tables are set so that the transmission interface A is selected for addresses other than these.

As shown in the upper address information "133" and the upper address information "133.141.77.59", a relationship where all of one upper address information and a part of the other upper address information match (hereinafter, referred to as "higher address information"). When such a relationship is called an inclusive relationship), the address control table corresponding to the divided address immediately after the matching portion is made to correspond to all the divided address information other than the divided address information of the longer upper address information. Then, a transmission interface name corresponding to the shorter upper address information is set. In the example of FIG. 19, in the second address control table 92, the divided address information “0” other than the divided address information “141”
~ "140", "142" ~ "255"
The transmission interface name B is set.

Next, the processing flow of the network address search method will be described. For example, when transmitting a packet destined for the IP address “133.141.77.59”, first, the uppermost divided address information “133” of the IP address is used, and the first address control table 91 in the first address control table 91 is used. Reference is made to information corresponding to the division address information "133" (information stored at the position indicated by the pointer A133). Here, since the search end / continuation flag 912 is “1”, the next table pointer 913
To obtain the pointer B000 set as.

Next, a predetermined block of the second address control table 92 indicated by the acquired pointer B000 is referred to. Then, using the second divided address information “141”, information corresponding to the divided address information “141” in a predetermined block of the second address control table 92 (information stored at the position indicated by the pointer B141) See Here, the search end / continuation flag 922 is “1”.
Therefore, the pointer C000 set as the next table pointer 923 is obtained.

Next, a predetermined block of the third address control table 93 indicated by the acquired pointer C000 is referred to. Then, using the third divided address information “77”, information corresponding to the divided address information “77” in a predetermined block of the third address control table 93 (information stored at the position indicated by the pointer C077) See Here, since the search end / continuation flag 932 is “1”, the pointer area D000 set as the next table pointer 933 is acquired.

Next, a predetermined block of the fourth address control table 94 indicated by the acquired pointer area D000 is referred to. Then, the lowest divided address information “59”
And information corresponding to the divided address information "59" in a predetermined block of the fourth address control table 94 (information stored at the position indicated by the pointer area D059).
See Here, since the search end / continuation flag 942 is “0”, the information 9 indicating the transmission interface
With reference to 44, the transmission interface C is selected. Thus, the IP address “133.141.77.5.
9 ”,“ Send packet to interface C
Is sent as a search result.

Next, the IP address "133.141.
A case of transmitting a packet addressed to “78.244” will be described. In this case, first, the uppermost division address information “133” of the IP address is used, and the division address information “13” in the first address control table 91 is used.
3 (information stored at the position indicated by the pointer A133). Here, since the search end / continuation flag 912 is “1”, the pointer B000 set as the next table pointer 913 is obtained.

Next, a predetermined block of the second address control table 92 indicated by the acquired pointer B000 is referred to. Then, using the second divided address information “141”, information corresponding to the divided address information “141” in a predetermined block of the second address control table 92 (information stored at the position indicated by the pointer B141) See Here, the search end / continuation flag 922 is “1”.
Therefore, the pointer C000 set as the next table pointer 923 is obtained.

Next, a predetermined block of the third address control table 93 indicated by the acquired pointer C000 is referred to. Then, using the third divided address information “78”, information corresponding to the divided address information “78” in a predetermined block of the third address control table 93 (information stored at the position indicated by the pointer C078) See Here, since the search end / continuation flag 932 is “0”, the transmission interface B is selected with reference to the information 934 indicating the transmission interface. in this way,
For the IP address “133.141.78.244”, routing information “transmit packet from transmission interface B” is obtained as a search result.
Since the routing information is obtained from the third divided address information and the third address control table, the fourth divided address information and the fourth address control table are not used.

[0025]

However, according to the above-mentioned prior art, when upper address information has an inclusion relation, a large number of routing information corresponding to the shorter upper address information must be set. There is a problem that it takes time for the processing and the setting change processing, and the load increases and the cost increases. In addition, since routing information is acquired only for the address control table for all the upper address information, when the upper address information is large, the data amount of the lower address control table increases, the memory consumption increases, and the cost increases. There was a problem.

Further, according to the conventional network address search method, when the address mask which can be set with the upper address information becomes large, the second address control table,
It was necessary to have a large amount of the third address control table and the fourth address control table. As an example, in order to be able to set 1000 entries in any combination of the upper address information and the paired address mask (the set of the upper address information and the paired address mask is hereinafter referred to as an entry), the second address control table In the above, if B000 to B255 is one block, it is necessary to have 256 blocks. Similarly, if C000 to C255 is one block, in the third address control table, it is necessary to have 1000 blocks. In this case, if D000 to D255 are one block, it is necessary to possess 1000 blocks. In other words, the second address control table, the third address control table, and the fourth address control table respectively hold the number of entries that can be set in any combination or the number of blocks corresponding to the smaller of the maximum number of branches. In the case where the address control table is configured by a memory, a large amount of memory is required.

The present invention has been made in view of the above, and it is possible to shorten the time required for the setting process and the setting change process, reduce the load of the setting process and the setting change process, and reduce the cost. It is an object of the present invention to obtain a routing information search device and a computer-readable recording medium that stores routing information search control data.

[0028]

Means for Solving the Problems The above-mentioned problems are solved,
In order to achieve the object, in a routing information search device according to the present invention, a second address obtained by cutting out first address information included in processing data processed by a communication network device according to a plurality of network masks. A routing information search device for searching for routing information indicating a transmission route or processing content of the processing data according to information, wherein the first address information is divided hierarchically every predetermined number of bits. First storage means for storing first search control information provided in a tree shape corresponding to each layer of the address information; and the first search control information stored in the first storage means. Searching means for searching for routing information, wherein each of the first search control information is provided for each of the divided address information of its own hierarchy. If all of the combined address information obtained by combining the first to the uppermost divided address information coincides with a part of the second address information cut out from the uppermost part, the lower-level first search control information is referred to. In the case where a part of the combination address information or a part of the divided address information truncated from the lowest order of the combination address information matches all of the second address information, Irrespective of whether or not it includes information used for referring to the first search control information of
Routing information corresponding to the second address information or information used for referring to the routing information, wherein the search unit sequentially searches, from the highest order, divided address information of the first address information being searched and the first address information. Referring to the search control information, if the first search control information includes information used for referring to the lower first search control information corresponding to the divided address information, the lower first search control Information, the first search control information does not include information used for referring to the lower-order first search control information corresponding to the divided address information, and is used for referencing the routing information or the routing information. In the case where the first search control information is included, the first search control information is used for referring to the lower first search control information corresponding to the divided address information. And the routing information or the information used for referring to the routing information is not included, and the upper first search control information corresponds to the routing information or the information used for referring to the routing information in accordance with the upper division address information. In the case where the routing information is included, the routing information is obtained.

According to the present invention, the first search control information provided in the form of a tree is stored so as to correspond to each layer of the divided address information obtained by hierarchically dividing the first address information by a predetermined number of bits. Each of the first search control information is, for each of the divided address information of its own hierarchy, the combination of all of the combined address information from the divided address information to the uppermost divided address information is any of the second address information. When the partial address information matches a part of the divided address information that is obtained by cutting out a part of the divided address information from the least significant part of the combined address information or the least significant part of the combined address information. If the truncated part matches all of the second address information,
Regardless of whether or not it includes information used for referring to lower first search control information, it includes routing information corresponding to the second address information or information used for referring to the routing information. As a result, even if all of the certain second address information coincides with a part of the other second address information cut out from the highest level, that is, even if the second address information has an inclusive relation, it is added to the shorter second address information. There is no need to set a lot of corresponding routing information.

The routing information retrieval apparatus according to the next invention further comprises a second storage means for storing valid information indicating whether each of the routing information is valid or invalid. The means retrieves the routing information based on the valid information stored in the second storage means.

According to the present invention, valid information indicating whether each piece of routing information is valid or invalid is stored. Thus, the routing information can be easily invalidated, and the invalidated routing information can be easily validated.

In the routing information search device according to the next invention, the second address information, a network mask corresponding to the second address information, and a routing corresponding to the second address information are further provided. And a third storage means for storing second search control information including information or information used for referring to the routing information, wherein the first search control information is provided for each divided address information of its own hierarchy. In the case where all of the combined address information obtained by combining the divided address information and the uppermost divided address information coincides with a part of the second address information cut out from the uppermost part, the second The search means includes information used for referring to search control information or information used for referring to lower first search control information. When the information includes information used for referring to the second search control information corresponding to the divided address information being referred to, the second search control information is referred to, and the network included in the second search control information is referred to. When the mask multiplied by the first address information being searched corresponds to the second address information included in the second search control information, the routing information corresponding to the second address information is obtained. It is characterized by the following.

According to the present invention, the second address information, the network mask corresponding to the second address information, the routing information corresponding to the second address information, or the information used for referring to the routing information, ,
Is stored, and the first search control information includes, for each of the divided address information of its own hierarchy, the combined address information obtained by combining from the divided address information to the highest divided address information. Everything is any second
If the address information matches a part of the address information extracted from the top, the information includes information used for referring to the second search control information or information used for referring to the lower first search control information. Thereby, the data amount of the first search control information can be reduced.

In the routing information search apparatus according to the next invention, the first search control information indicates which part of the first address information is divided by each divided address information of its own hierarchy. Is included.

According to the present invention, the first search control information includes information indicating which part of the first address information each divided address information of its own hierarchy is divided. Accordingly, addresses of a plurality of types of protocols can be handled, and by preparing first search control information corresponding to each protocol, addresses of a plurality of types of protocols can be processed by one routing information search device. Can be.

In the routing information search device according to the next invention, the processing data includes a plurality of pieces of the first address information for one piece of the processing data, and the search means includes the plurality of pieces of the first address information. A plurality of search means are provided corresponding to one piece of address information, and the plurality of search means respectively search for corresponding routing information.

According to the present invention, the routing information corresponding to each of the plurality of first address information included in one piece of processing data is searched. Accordingly, when one piece of processing data includes a plurality of pieces of first address information, it is possible to search for routing information corresponding to each piece of first address information.

In a routing information search device according to the next invention, the plurality of search means are connected in series,
It is characterized in that a lower search means obtains information on a search result from a higher search means and searches for routing information based on the information on the search result.

According to the present invention, the lower-order search means acquires information on the search result from the higher-order search means, and searches for routing information based on the information on the search result. Thus, a search result in which a plurality of pieces of first address information included in one piece of processing data are associated can be obtained.

In the routing information search device according to the next invention, the search means comprises a plurality of hierarchy search means provided for each hierarchy of the divided address information, and the plurality of hierarchy search means comprises: A search process of the routing information in each layer is performed by pipeline processing.

According to the present invention, a plurality of hierarchical search means perform a search for routing information in each hierarchy by pipeline processing. This makes it possible to speed up the search process.

In a computer-readable recording medium recording the routing information search control data according to the next invention, the first address information included in the processing data processed by the communication network device is determined according to a plurality of network masks. A computer-readable recording medium recording routing information search control data used for routing information search for searching routing information indicating the transmission route or processing content of the processing data in accordance with the second address information cut out. The routing information search control data includes first search control information provided in a tree shape corresponding to each layer of divided address information obtained by hierarchically dividing the first address information by a predetermined number of bits. Wherein the first search control information is provided for each divided address information of its own hierarchy. If all of the combined address information obtained by combining the divided address information and the uppermost divided address information matches a part of the second address information cut out from the uppermost part, the lower first search is performed. Including the information used for referring to the control information, the whole of the combination address information or the part obtained by truncating the part of the division address information from the lowest order of the combination address information coincides with the whole of any of the second address information. In this case, the information includes routing information corresponding to the second address information or information used for referring to the routing information, regardless of whether or not the information includes information used for referring to the lower first search control information. And

According to the present invention, the routing information retrieval control data is provided in the form of a first tree which is provided in a tree shape in such a manner that the first address information is hierarchically divided by a predetermined number of bits and corresponds to each layer of the divided address information. Including the search control information of the first
Is the search control information for each of the divided address information of its own hierarchy, all of the combined address information from the divided address information to the highest divided address information are combined from the top of any of the second address information. In the case where a part of the divided address information coincides with a part of the divided address information, the part includes information used for referring to the lower first search control information, and a part of the divided address information is truncated from the entire combined address information or the lowest part of the combined address information. If the information matches all of the second address information, the routing information corresponding to the second address information regardless of whether the information includes information used for referring to the lower first search control information or not. Alternatively, the information includes information used for referring to the routing information. As a result, all of the certain second address information coincides with a part of the other second address information cut out from the top.
That is, even in the case of the inclusion relation, it is not necessary to set a large number of routing information corresponding to the shorter second address information.

In a computer-readable recording medium on which the routing information search control data according to the next invention is recorded, the routing information search control data further determines whether each of the routing information is valid or invalid. It is characterized by including routing information search control data including valid information shown.

According to the present invention, the routing information search control data further includes routing information search control data including valid information indicating whether each routing information is valid or invalid. Thus, the routing information can be easily invalidated, and the invalidated routing information can be easily validated.

In a computer-readable recording medium storing the routing information search control data according to the next invention, the routing information search control data further includes the second address information and the second address information. And second search control information including a network mask corresponding to the second address information and routing information corresponding to the second address information or information used for referring to the routing information.

According to this invention, the routing information search control data further includes the second address information and the second address information.
The second search control information includes a network mask corresponding to the second address information, and routing information corresponding to the second address information or information used for referring to the routing information. Thereby, the data amount of the first search control information can be reduced.

In a computer-readable recording medium having recorded therein routing information search control data according to the next invention, the first search control information is such that each divided address information of its own hierarchy is the first address information. The information includes information indicating which part is divided.

According to the present invention, the first search control information includes information indicating which part of the first address information each divided address information of its own hierarchy is divided. This makes it possible to correspond to the addresses of a plurality of types of protocols. By preparing the first search control information corresponding to each protocol, it is possible to process the addresses of the plurality of types of protocols with one routing information search device. Can be.

Here, the “computer-readable recording medium” is a magnetic disk such as a floppy (registered trademark) disk, or a semiconductor memory (a cartridge, a PC card, or the like) such as a ROM, an EPROM, an EEPROM, or a flash ROM. CD-ROM,
It includes a "portable physical medium" such as an optical disk such as a DVD and a magneto-optical disk such as an MO, and a "fixed physical medium" such as a ROM, a RAM, and a hard disk incorporated in various computer systems. Further, the “computer-readable recording medium” includes a communication medium for holding data and programs for a short period of time, such as a communication line for transmitting data and programs via a network such as a LAN, a WAN, or the Internet. You may. Note that the “data” is not necessarily limited to a single data, and includes data recorded in a distributed manner on a plurality of computer-readable recording media.

[0051]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described.
This will be described in detail with reference to the drawings. The present invention is not limited by the embodiment.

Embodiment 1 The routing information search device according to the first embodiment of the present invention is provided integrally with a communication network device such as a relay device or a terminal device connected to a communication network, and has routing information (communication) corresponding to the longest match of the address mask. A description will be given of an example of a routing information search device that searches for information indicating a transmission route of process data processed by a network device and information of the process. The processing data processed by the communication network device may be any data. Here, a case will be described as an example where a packet including address information of a 32-bit IP address is processed.

FIG. 1 is a diagram showing a schematic configuration of a communication network device 1 according to the first embodiment of the present invention. The communication network device 1 acquires address information, and searches for routing information corresponding to the address information based on an address control table and a routing information table, which will be described later, and a packet processed by the communication network device 1. And an address search requesting unit 16 that sends address information (for example, information of a transmission destination address) included in the search control unit 10 to the search control unit 10 and obtains routing information output by the search control unit 10 as a search result.

The search control unit 10 includes the address search request unit 1
When the address information is acquired from the address information No. 6, the divided address information is generated by hierarchically dividing the address information by predetermined bits in order from the most significant bit. The number of layers of the divided address information may be any number. Here, 8 bits, 1
A case where address information is divided into four by eight bits using upper address information of 6 bits, 24 bits and 32 bits, that is, a case where the layer of the divided address information is four layers will be described as an example.

The search control unit 10 includes a first address control unit 11, a second address control unit 12, a third address control unit 13, and a fourth address control unit 14 corresponding to each layer of the divided address information. A routing information unit 15 is provided for each of the control units 11 to the fourth address control unit 14. The first address control unit 11 stores a highest-order address control table to be described later, and performs a routing information search process (address search process) with reference to the highest-order divided address information and a highest-order address control table to be described later. Do. Similarly, the second address control unit 12
Stores a second highest-order address control table, which will be described later, and performs a search process for routing information with reference to the second highest-order address information and a second highest-order address control table, which will be described later.

Similarly, the third address control unit 13 stores the third highest address control table described later, and stores the third highest address control information and the third highest address control table described later. To perform routing information search processing. Similarly, the fourth address control unit 14 stores the fourth highest address control table described later, and refers to the fourth highest address control table described later and the fourth highest address control table described later. To search for routing information.
The search control unit 10 stores a routing information table described later, and outputs a transmission interface name as routing information of a search result.

FIG. 2 is a diagram showing a configuration of the address control table according to the first embodiment. This address control table is formed in a tree shape corresponding to each hierarchy, and includes a first address control table D11 at the highest level, a second address control table D12 at the second level from the highest level, and a third address control table D12 at the highest level. A third address control table D13,
And a fourth address control table D14, which is the fourth from the highest.

The first address control table D11 is used for a search process based on the highest division address information (highest 8 bits) of the address information.
A search in which any of the search flags “invalid”, “search completed”, or “search continued” is set at the positions indicated by the pointers Aa000 to Aa255 corresponding to the uppermost division address information (decimal number). Flag area D11
2, a root flag area D113 in which a root flag of any of "discard", "no root", "default", and "block" is set, and a position of a block of the lower second address control table D12 to be referred to And a routing pointer area D115 for storing a routing information table pointer indicating a position in the routing information table to be referred to.

Similarly, the second address control table D12
Is used for a search process based on the second divided address information (the 9th to 16th bits) of the address information. It includes the number of branches from D11. That is, in the search flag area D112 of the first address control table D11, a lower-order address control table (first address control table D11
The block includes the number of blocks for which “continue search” indicating that the search process using the second address control table D12) is to be continued is set.

The pointers Ba000 to Ba255 corresponding to the second divided address information from 0 to 255
And the like, a search flag area D122 in which a search flag of “invalid”, “end of search” or “continuation of search” is set, and “discard”, “no route”, and “default”, respectively. Or a route flag area D123 in which any of the route flags of “block” is set
And the lower third address control table D13 to be referred to
A next table pointer area D124 for storing a pointer indicating the position of the block of interest, and a routing pointer area D125 for storing a routing information table pointer indicating the position in the routing information table to be referred to.

Similarly, the third address control table D13
Is used for a search process based on the third divided address information (17th to 24th bits) of the address information, and blocks corresponding to the third divided address information from 0 to 255 are stored in the second address control table It includes the number of branches from D12. That is, in the search flag area D122 of the second address control table D12, a lower address control table (the second address control table D1) is stored.
No. 2 includes the number of blocks for which “search continuation” indicating that the search process using the third address control table D13) for continuation 2 is continued is set.

The pointers Ca000 to Ca255 corresponding to the third divided address information from 0 to 255
, A search flag area D132 in which a search flag of “invalid”, “end of search”, or “continuation of search” is set, and “discard”, “no route”, and “default”, respectively. Or a route flag area D133 in which any of the route flags of “block” is set
And the lower fourth address control table D14 to be referred to
And a routing pointer area D135 for storing a routing information table pointer indicating a position in the routing information table to be referred to.

Similarly, the fourth address control table D14
Is used for search processing based on the fourth divided address information (25th to 32nd bits) of the address information, and blocks corresponding to the fourth divided address information from 0 to 255 are stored in the third address control table. It includes the number of branches from D13. That is, in the search flag area D132 of the third address control table D13, a lower address control table (third address control table D1) is stored.
No. 3 includes the number of blocks in which “continue search” indicating that the search process using the fourth address control table D14) is continued is set.

Then, pointers Ca000 to Ca255 corresponding to the fourth divided address information from 0 to 255
, A search flag area D142 in which a search flag of "invalid" or "end of search" is set, and a search flag area D142 of "discard", "no route", "default" or "block". It includes a route flag area D143 in which one of the route flags is set, a next table pointer area D144, and a routing pointer area D145 for storing a routing information table pointer indicating a position in the routing information table to be referred to.

Pointers Aa000 to Aa255, Ba0
00 to Ba255, Ca000 to Ca255, Da00
0 to Da255 are the values of the divided address information 0 to 0, respectively.
255, which indicates the position (one row of the address control table shown in FIG. 2) where data corresponding to each piece of divided address information is stored, and the position of each block. Here, for the sake of simplicity, the values of the corresponding divided address information are indicated by adding Aa, Ba, Ca, Da, etc., respectively. The lowercase letters indicate blocks. For example,
The pointer starting with Ba indicates one block, and Bb
A pointer that starts with indicates another block.

Search flag areas D112, D122, D1
“Invalid” set in 32 and D142 indicates that the routing information should be obtained based on the information of the upper address control table, and “End of search” indicates that the search processing using the lower address control table is not continued. Indicates that the routing information is to be obtained using the address control table, and “continue search” indicates that the search process using the lower address control table is continued.

Route flag areas D113, D123, D
“Discard” set in 133 and D143 is routing information indicating the processing content of “discard the packet”, “no route” indicates that there is no route for transmitting the packet, and “default” indicates This indicates that the information of the transmission interface set as a default in a routing information table to be described later is referred to.
D135 and D145 indicate that the routing information table pointer is stored.

Next table pointer area D114, D12
The pointers stored in D4, D134 and D144 indicate the position of the block of the lower address control table to be referred to. For example, a pointer Ba000 indicating the position of the first block of the second address control table D12 is stored corresponding to the highest division address “133”. In the case of the second block, the pointer Bb000 is stored. By using the pointer stored in the next table pointer area, the highest-order first address control table D1
A predetermined block of the lower address control table can be referred to in order from 1.

Routing pointer areas D115, D12
The routing information table pointer stored in D5, D135, or D145 indicates a position in the routing information table to be referred to. FIG. 3 is a diagram illustrating a configuration of the routing information table D15 according to the first embodiment. The routing information table D15 includes routing pointer areas D115, D125, and D13 of each address control table.
5, a transmission interface area D153 in which an interface name for transmitting a packet is set at a position indicated by the routing information table pointer stored in D145 and a position for “default”, and whether information in the transmission interface area D153 is valid or not. And an effective flag area D152 for setting an effective flag indicating the following.

Further, the routing information table D15 may include information describing the processing to be executed when the referenced valid flag indicates "invalid" (packet discard, alarm, etc.). This makes it possible to easily set and change the processing when the information of the referred transmission interface area D153 is invalid.

Hereinafter, the upper division address information (information obtained by cutting out the address information in accordance with the address mask) and the address mask are divided into 8 bits, and the four numbers are separated by dots, each of which is represented by a decimal number. . The address mask has the same length as the address information, and validates the address information corresponding to the bit where a binary "1" stands. For example, the address mask “255.0.0.0” can be represented by “1111” in binary.
1111.000000000000000000000
000000 ”, and the upper 8 bits of the address information are validated.

In the example shown in FIG.
3.141.77.59 and a pair of address mask 255.
255.255.255 and upper division address information 13
3.141.77.60 and a pair of address mask 255.
255.255.255 and upper division address information 13
3.141.77 and paired address mask 255.25
5.255.0 and upper division address information 133.14
Address mask 255.255.25 paired with 1.76
4.0, an address mask 255.255.0.0 paired with the upper division address information 133.141, and an address mask 255.0.
0.0 is set.

Then, the first address control table D11
In all of the positions other than the position indicated by the pointer Aa 133 corresponding to the uppermost division address information “133”, “search end” is displayed in the search flag area D112.
"Discard" is set in the root flag area D113, "invalid" is set in the next table pointer area D114, and "invalid" is set in the routing pointer area D115. In the second address control table D12, the search flag area D122, the root flag area D123, and the next table pointer area D124 are located at all positions other than the position indicated by the pointer Ba141 corresponding to the second divided address information "141". , "Invalid" is set in the routing pointer area D125.

In the third address control table D13, the third divided address information "76" and "77"
In all positions other than the positions indicated by the pointers Ca076 and Ca077, the search flag area D132, the root flag area D133, the next table pointer area D134, and the routing pointer area D135
Is set to “invalid”. In the fourth address control table D14, the pointer Da05 corresponding to the fourth divided address information "59" and "60"
9, the search flag area D142, the root flag area D143, the next table pointer area D144, and the routing pointer area D145 are set to "invalid" at all positions other than the position indicated by the pointer Da060.

If the divided address information is not divided according to the length of the upper divided address information, lower bits (shorter than the divided address information) are added to the upper divided address information to match the division of the divided address information. For each of them, the setting corresponding to the upper division address information is performed. For example, if the upper division address information is "2
52 ”and the address mask is“ 252.0.0.0 ”(2
"11111100.000000000000 in base number
0000.000000000 "), in the first address control table D11, the setting corresponding to the upper-level divided address information" 252 "is performed for the divided address information" 252 "," 253 "," 254 ", and" 255 ". .

Here, when a part of the divided address information corresponds to another upper divided address information, the setting corresponding to the other upper divided address information is performed for the part of the divided address information. For example, when the division address “253” corresponds to the upper division address information “253”, the division address “253” is not set to correspond to the upper division address information “252”, but is set to the higher division address information “253”. Make the corresponding settings.

Now, the communication network device 1
Has been described, but each component of the communication network device 1 is conceptually functional and does not necessarily have to be physically configured as illustrated. For example, all or a part of the processing functions of the communication network device 1 may be replaced by a CPU (Central Process
ng Unit) and a program interpreted and executed by the CPU. That is, the ROM (not shown) stores a computer program that gives instructions to the CPU in cooperation with an OS (Operating System) or the like and causes the CPU to perform various processes. And CPU
Performs various processes according to this program.

Further, all or a part of the processing functions of the communication network device 1 can be realized as hardware by wired logic. Further, each component and processing function of the communication network device according to the second to sixth embodiments described later can be similarly configured by a CPU or a wired logic.

In the above configuration, the operation of the first embodiment will be described with reference to the flowchart of FIG. FIG. 4 is a flowchart illustrating the flow of the operation of the search control unit 10 according to the first embodiment. The search control unit 10 divides the address information from the address search request unit 16 and generates divided address information (S1). Then, the n-th (n is an integer of 1 to 4 and an initial value of 1) address control unit refers to the n-th divided address information and the n-th address control table. Then, it is determined whether or not the search flag stored at the position corresponding to the divided address information is “continuation” (S2).

If the search flag is “continue”,
It is determined whether or not the route flag stored at the position corresponding to the divided address information is "invalid" (S9).
If the route flag is "invalid", 1 is added to n, and the process returns to step S1. The routing information table pointer is stored (S10), 1 is added to n, and the process returns to step S1. Note that (n +
1) When the first search flag becomes “invalid”, the route flag and the routing information table pointer may be acquired by referring to the n-th address control table again.

On the other hand, if the search flag is not "continue", it is determined whether the search flag is "invalid" (S3). If the search flag is not "disabled,
The process proceeds to step S4 with reference to the route flag and the routing information table pointer stored at the position corresponding to the divided address information. On the other hand, if the search flag is "invalid", the process proceeds to step S4 with reference to the (n-1) th route flag and the routing information table pointer stored in step S10 (S11). In step S4, it is determined whether or not the referenced route flag is "discard". If the referred route flag is “discard”, the address search request unit 1
6 is returned with routing information of "discard the packet" (S12), and the process is terminated.

On the other hand, if the referenced route flag is not "discard", the route flag is set to "no route".
Is determined (S5). If the route flag is "no route", the address search request unit 16 is replied that "there is no packet route" (S1).
3), end the process. On the other hand, if the route flag is not “no route”, the routing information table D1
In S5, the validity flag stored at the position indicated by the referencing routing information table pointer is referred to (S5).
6) It is determined whether the valid flag is "invalid" (S7).

If the valid flag is "invalid",
Proceeding to step S13, if the validity flag is not "invalid", that is, if it is "valid", the validity flag is stored in the transmission interface area D153 at the position indicated by the referencing routing information table pointer in the routing information table D15. The transmission interface name is answered to the address search request unit 16 (S8), and the process ends.

Next, a specific IP address will be described as an example. For example, if the destination IP address is "0.
When searching for routing information for a packet that is “128.128.128”, the address search request unit 16
Sends address information to the search control unit 10 and requests address search (search for routing information). In the search control unit 10 receiving this request, first, the first address control unit 11 uses the uppermost divided address information “0” and stores the divided address information at the position indicated by the pointer Aa000 in the first address control table D11. Data (search flag, etc.).

Since "search end" is set in the search flag area D112 and "invalid" is set in the routing pointer area D115, the root flag area D1 is set.
13, "discard" is obtained as routing information.
Then, “discard” is output to the address search request unit 16. That is, if the IP address is “0.128.12
In the case of "8.128", the search control unit 10 notifies the address search request unit 16 of the routing information "discard" indicating the processing content of "discard the packet". Upon receiving this notification, the address search request unit 16 sends the I
The packet whose P address is “0.128.128.128” is discarded.

As described above, in the packet whose transmission destination IP address is "0.128.128.128", the search processing of the routing information is performed using only the uppermost division address information "0". . The same applies to other IP addresses having the highest-order divided address information “0”, that is, packets addressed to the IP address corresponding to the address mask “255.0.0.0” and the upper-order divided address information “0”. , The search result of the routing information is “discarded”. Then, those packets are discarded.

Next, the operation corresponding to the longest match of the address mask will be described in the order of case 1 to case 4. In the following description, “x1”, “x
2 ”and“ x3 ”indicate an arbitrary value from 0 to 255. Upper division address information "133.141.77.5"
9 ", address mask" 255.255.255.25 "
5 corresponding to the IP address “133.141.77.
The routing information search result of “59” (result of the routing information search process) is “transmission interface D”,
This is referred to as Case 1. Similarly, the upper division address information “133.141.77.60” and the address mask “2”
The routing information search result of the IP address “133.141.77.60” corresponding to “55.255.255.255” is “no route”.

The upper division address information "133.141.
76 "and the address mask" 255.255.254.
0 "corresponding to the IP address" 133.141.76.
x1 ”and IP addresses other than case 1 and case 2 (IP addresses“ 133.141.77.59 ”,“ 133.14
1.77.60 ") IP address" 133.14 "
1.77. The routing information search result of “x1” is “transmission interface C”.

The upper division address information “133.14”
1 "and an IP address" 133.141.x2.x1 "corresponding to the address mask" 255.255.0.0 "
(However, the IP address "13
3.141.77.59 "," 133.141.77.
60 "," 133.141.76.x1 "," 133.
141.77. The routing information search result (excluding “x1”) is “transmission interface B”, which is referred to as case 4.

"IP address 133.x3.x2.x1" corresponding to upper division address information "133" and address mask "255.0.0.0" (cases 1 to 3).
In case 4, the IP address “133.141.77.5.
9 "," 133.141.77.60 "," 133.1
41.76. x1 "," 133.141.77.x
1) and “133.141.x1.x2”), the routing information search result is “transmission interface A”.

(Case 1) IP address “133.14”
In case 1 of processing a packet addressed to "1.7.59.59", first, the address search request unit 16 transmits address information to the search control unit 10 to request an address search. Upon receiving this request, the search control unit 10
The address control unit 11 determines that the uppermost division address information “1”
33, and refers to the data (search flag and the like) stored in the first address control table D11 at the position indicated by the pointer Aa133. Then, since “search continuation” is set in the search flag area D112, the pointer Ba00 indicated in the next table pointer area D114
0, and sends the pointer Ba000 to the second address control unit 12.

The second address control unit 12, which has received the pointer Ba000, sets the second divided address information “14”.
Using "1", the second address control table D12 refers to the data (search flag and the like) stored at the position indicated by the pointer Ba141 in the block indicated by the pointer Ba000. Then, the search flag area D12
Since “continuation of search” is set in 2, the pointer Ca000 indicated in the next table pointer area D124 is obtained, and the pointer Ca000 is sent to the third address control unit 13.

Upon receiving the pointer Ca000, the third address control unit 13 sets the third divided address information "77"
And in the third address control table D13,
Pointer C in the block indicated by pointer Ca000
Reference is made to data (search flag, etc.) stored at the position indicated by a077. Since “search continuation” is set in the search flag area D132, the pointer Da000 indicated in the next table pointer area D134 is obtained, and the pointer Da000 is sent to the fourth address control unit 14.

When the fourth address control unit 14 receives the pointer Da000, the fourth address control unit 14 outputs the fourth divided address information “59”.
And in the fourth address control table D14,
Pointer D in the block indicated by pointer Da000
Reference is made to data (search flag, etc.) stored at the position indicated by a059. Since "search end" is set in the search flag area D142 and "block" is set in the root flag area D143, the routing information table pointer D indicated in the routing pointer area D145 is obtained. Then, the routing information table pointer D is sent to the routing information section 15.

The routing information section 15, which has received the routing information table pointer D, refers to the data (valid flag, etc.) stored in the routing information table D15 at the position indicated by the routing information table pointer D. Then, “valid” indicating that the transmission interface area D153 is valid is set in the valid flag area D152.
Is set, the transmission interface area D1
The transmission interface name “D” shown in 53 is obtained.
Then, the transmission interface name “D” is sent to the address search request unit 16. The address search request unit 16 that has received the transmission interface name “D” transmits a packet from the transmission interface D.

(Case 2) Next, the IP address 13
A case 2 for processing a packet addressed to 3.141.77.60 will be described. In Case 2, first, the address search request unit 16 transmits address information to the search control unit 10 and requests an address search. Upon receiving this request, the search control unit 10 sends the first address control unit 11
Uses the highest-order divided address information “133” and refers to data (search flag and the like) stored in the first address control table D11 at the position indicated by the pointer Aa133. Then, since “search continuation” is set in the search flag area D112, the next table pointer area D
The pointer Ba000 indicated by 114 is acquired, and the pointer Ba000 is sent to the second address control unit 12.

The second address control unit 12, which has received the pointer Ba000, sets the second divided address information “14”.
Using "1", the second address control table D12 refers to the data (search flag and the like) stored at the position indicated by the pointer Ba141 in the block indicated by the pointer Ba000. Then, the search flag area D12
Since “continuation of search” is set in 2, the pointer Ca000 indicated in the next table pointer area D124 is obtained, and the pointer Ca000 is sent to the third address control unit 13.

Upon receiving the pointer Ca000, the third address control unit 13 sets the third divided address information "77"
And in the third address control table D13,
Pointer C in the block indicated by pointer Ca000
Reference is made to data (search flag, etc.) stored at the position indicated by a077. Since “search continuation” is set in the search flag area D132, the pointer Da000 indicated in the next table pointer area D134 is obtained, and the pointer Da000 is sent to the fourth address control unit 14.

The fourth address control unit 14, which has received the pointer Da000, sets the fourth divided address information "60"
And in the fourth address control table D14,
Pointer D in the block indicated by pointer Da000
Reference is made to data (search flag and the like) stored at the position indicated by a060. Then, "search end" is set in the search flag area D142, and the routing pointer area D1 is set.
Since “invalid” is set in 45, “no route” in the route flag area D143 is acquired. That is, I
When the P address is “133.141.77.60”, the search control unit 10 notifies the address search request unit 16 that there is no transmission route. The address search request unit 16 that has received the notification performs a process when there is no packet transmission route.

(Case 3) Next, the IP address "13
3.141.76. Case 3 for processing a packet addressed to “x1” will be described. In case 3,
First, the address search request unit 16 transmits address information to the search control unit 10 and requests an address search. Upon receiving this request, the search control unit 10 sets the first address control unit 1
1 uses the highest division address information “133”,
Pointer Aa133 of first address control table D11
Refer to the data (search flag etc.) stored at the position indicated by. Then, since “search continuation” is set in the search flag area D112, the next table pointer area D
The pointer Ba000 indicated by 114 is acquired, and the pointer Ba000 is sent to the second address control unit 12.

Upon receiving the pointer Ba000, the second address control unit 12 sets the second divided address information “14”.
Using "1", the second address control table D12 refers to the data (search flag and the like) stored at the position indicated by the pointer Ba141 in the block indicated by the pointer Ba000. Then, the search flag area D12
Since “continuation of search” is set in 2, the pointer Ca000 indicated in the next table pointer area D124 is obtained, and the pointer Ca000 is sent to the third address control unit 13.

Upon receiving the pointer Ca000, the third address control unit 13 sets the third divided address information "76"
And in the third address control table D13,
Pointer C in the block indicated by pointer Ca000
Reference is made to data (search flag and the like) stored at the position indicated by a076. Then, since "search end" is set in the search flag area D132 and "block" is set in the root flag area D133, the routing information table pointer C indicated in the routing pointer area D135 is obtained. Then, the routing information table pointer C is sent to the routing information section 15.

The routing information section 15, which has received the routing information table pointer C, refers to the data (valid flag, etc.) stored in the routing information table D15 at the position indicated by the routing information table pointer C. Then, since “valid” is set in the valid flag area D152, the transmission interface name “C” indicated in the transmission interface area D153 is obtained. Then, the transmission interface name “C” is entered in the address search request unit 1.
Send to 6. The address search request unit 16 that has received the transmission interface name “C” transmits a packet from the transmission interface C.

The IP address “133.141.7”
7. x1 ”(however, the IP address“ 133.141.
77.59 "and" 133.141.77.60 "), the address search request unit 16 first sends the address information to the search control unit 10 to perform the address search. Request. In the search control unit 10 receiving this request, the first address control unit 11 uses the highest-order divided address information “133” and stores the data stored at the position indicated by the pointer Aa 133 in the first address control table D11. (Search flag, etc.). Since “continue search” is set in the search flag area D112, the next table pointer area D114
And obtains the pointer Ba000 indicated by
000 to the second address control unit 12.

The second address control unit 12, which has received the pointer Ba000, sets the second divided address information “14”.
Using "1", the second address control table D12 refers to the data (search flag and the like) stored at the position indicated by the pointer Ba141 in the block indicated by the pointer Ba000. Then, the search flag area D12
Since “continuation of search” is set in 2, the pointer Ca000 indicated in the next table pointer area D124 is obtained, and the pointer Ca000 is sent to the third address control unit 13.

Upon receiving the pointer Ca000, the third address control unit 13 sets the third divided address information “77”
And in the third address control table D13,
Pointer C in the block indicated by pointer Ca000
Reference is made to data (search flag, etc.) stored at the position indicated by a077. Since “search continuation” is set in the search flag area D132, the pointer Da000 indicated in the next table pointer area D134 is obtained, and the pointer Da000 is sent to the fourth address control unit 14.

When the fourth address control unit 14 receives the pointer Da000, the fourth address control unit 14 sets the fourth divided address information “x1”
(However, except for the divided address information “59” and “60”), and stored in the fourth address control table D14 at a position corresponding to the divided address information “x1” in the block indicated by the pointer Da000. Refer to data (search flag etc.).

Since "invalid" is set in the search flag area D142, the root flag area D133 and the routing pointer area D135 at the position indicated by the pointer Ca077 in the upper third address control table D13 are referred to. Then, the route flag area D13
Since “block” is set in 3, the routing information table pointer C indicated in the routing pointer area D 135 is obtained. Then, the routing information table pointer C is sent to the routing information section 15.

Upon receiving the routing information table pointer C, the routing information section 15 refers to the data (valid flag, etc.) stored in the routing information table D15 at the position indicated by the routing information table pointer C. Then, since “valid” is set in the valid flag area D152, the transmission interface name “C” indicated in the transmission interface area D153 is obtained. Then, the transmission interface name “C” is entered in the address search request unit 1.
Send to 6. The address search request unit 16 that has received the transmission interface name “C” transmits a packet from the transmission interface C.

As described above, the third address control table D
Route flag area D133 for thirteen pointer Ca077
Is set to “block”, other upper division address information including upper division address information “133.141.77” (other upper division address information generated by adding lower bits to the upper division address information) For example,
When "133.141.77.10" is additionally set, only the portion corresponding to the bit to be added (for example, "10") needs to be changed, and the already set upper division address information is set. There is no effect on the part corresponding to. Similar effects can be obtained by setting "blocks" for other address control tables.

(Case 4) Next, the IP address "13
3.141. x2. x1 ”(however, the IP address“ 1
33.141.77. x1 "," 133.141.7 "
6. A case 4 for processing a packet addressed to the destination (excluding “x1”) will be described. In case 4, first,
The address search request unit 16 transmits address information to the search control unit 10 and requests an address search. In the search control unit 10 receiving this request, the first address control unit 11
Using the uppermost division address information “133”, the data (search flag and the like) stored at the position indicated by the pointer Aa133 in the first address control table D11 is referred to. Since “continue search” is set in the search flag area D112, the next table pointer area D114
And obtains the pointer Ba000 indicated by
000 to the second address control unit 12.

The second address control unit 12, which has received the pointer Ba000, sets the second divided address information “14”.
Using "1", the second address control table D12 refers to the data (search flag and the like) stored at the position indicated by the pointer Ba141 in the block indicated by the pointer Ba000. Then, the search flag area D12
Since “continuation of search” is set in 2, the pointer Ca000 indicated in the next table pointer area D124 is obtained, and the pointer Ca000 is sent to the third address control unit 13.

Upon receiving the pointer Ca000, the third address control unit 13 sets the third divided address information “x2”
(However, except for the divided address information “76” and “77”), and stored in the third address control table D13 at a position corresponding to the divided address information “x2” in the block indicated by the pointer Ca000. Refer to data (search flag etc.).

Since "invalid" is set in the search flag area D132, the root flag area D123 and the routing pointer area D125 at the position indicated by the pointer Ba141 in the upper second address control table D12 are referred to. Then, the route flag area D12
Since "block" is set in 3, the routing information table pointer B shown in the routing pointer area D125 is obtained. Then, the routing information table pointer B is sent to the routing information section 15.

Upon receiving the routing information table pointer B, the routing information section 15 refers to the data (valid flag, etc.) stored in the routing information table D15 at the position indicated by the routing information table pointer B. Then, since “valid” is set in the valid flag area D152, the transmission interface name “B” indicated in the transmission interface area D153 is obtained. Then, the transmission interface name “B” is entered in the address search request unit 1.
Send to 6. The address search request unit 16 that has received the transmission interface name “B” transmits a packet from the transmission interface B.

(Case 5) Next, the IP address "13
3. x3. x2. x1 ”(however, the IP address“ 13
3.141. x2. A case 5 for processing a packet addressed to the destination (excluding “x1”) will be described. In Case 5, first, the address search request unit 16 transmits address information to the search control unit 10 and requests an address search. In the search control unit 10 receiving this request, the first address control unit 11 sets the highest-order division address information “133”.
And refers to data (search flag and the like) stored in the first address control table D11 at the position indicated by the pointer Aa133. Then, the search flag area D112
Is set to “search continuation”, the pointer Ba000 indicated in the next table pointer area D114 is obtained, and the pointer Ba000 is sent to the second address control unit 12.

Upon receiving the pointer Ba000, the second address control unit 12 sets the second divided address information “x3”
(Except for the division address information “141”), and the data (search flag Etc.).

Since "invalid" is set in the search flag area D122, the root flag area D113 and the routing pointer area D115 at the position indicated by the pointer Aa133 in the upper first address control table D11 are referred to. Then, the route flag area D11
Since “default” has been set to No. 3, the routing information unit 15 is requested to execute a default search process.

Routing information part 1 receiving this request
Reference numeral 5 refers to data (valid flag, etc.) stored in a default position. Since “valid” is set in the valid flag area D152, the transmission interface name “A” indicated in the transmission interface area D153 is set.
Get. Then, the transmission interface name “A” is sent to the address search request unit 16. The address search request unit 16 that has received the transmission interface name “A” transmits a packet from the transmission interface A.

As described above, according to the first embodiment,
Since the longest match processing of the address mask in the address search is controlled by the search flag and the route flag of the address control table, when the value is equal to the divided address information, that is, the address of the pair with the upper divided address information having an inclusive relation. Even when it is necessary to set a plurality of masks, only the address control table corresponding to the address mask needs to be set. Even if the route information is additionally set, deleted, or changed, the update load of the address control table is changed. While keeping
This has the effect of reducing the processing time.

In the first embodiment described above, the address control table is stored in the address control unit. However, the address control table can be stored in various forms. If used, many address control tables can be referred to at high speed, so that many entries (a set of upper division address information and a pair of address masks) can be registered, and a high-speed search can be performed. In the first embodiment described above, the routing information search using the IP address is described as an example. However, other addresses having different address lengths may be used. In such a case, similar processing can be performed with a similar configuration, and similar effects can be obtained.

Further, information other than the address may be used for the routing information search, or the address and other information may be combined and used for the routing information search. For example, 5-byte information, which is a combination of an IP address and 1-byte information for traffic control, is used as address information, and this address information is divided into five pieces of divided address information for each byte to perform routing information search. You may. Also in such a case, similar processing can be performed in a similar configuration, and similar effects can be obtained.

Embodiment 2 Embodiment 2 of the present invention
In the first embodiment described above, the address control units are combined into one, and an address control table storage unit for storing the address control tables of the respective layers is provided independently of the address control unit. FIG. 5 is a diagram illustrating a schematic configuration of the communication network device 2 according to the second embodiment of the present invention. The basic configuration is the same as that of the first embodiment, and the same portions are denoted by the same reference numerals as in FIG. 1 and the description thereof is omitted, and only different portions will be described here.

The communication network apparatus 2 according to the first embodiment
Instead of the first address control unit 11 to the fourth address control unit 14, an address control unit 25 in which the functions of the first address control unit 11 to the fourth address control unit 14 are combined and a first address control table D11 are stored. A first address control table storage unit 21 for storing
, A third address control table storage 23 for storing the third address control table D13, and a fourth address control table storage 24 for storing the fourth address control table D14.
Is provided.

The first to fourth address control table storage units 21 to 24 are provided independently of the address control unit 25. Address control unit 25
Refers to the first to fourth address control tables D11 to D14 stored in the first to fourth address control table storage units 21 to 24, and refers to the first address control unit of the first embodiment. 11th to 4th
A function similar to that of the address control unit 14 is realized. The operation of the second embodiment is the same as that of the first embodiment, and the description is omitted.

As described above, according to the second embodiment,
One address control unit 25 reads out each address control table from the address control table storage unit corresponding to the divided address information of each layer, and intensively processes the divided address information of all layers. Can be reduced, and the circuit scale for the routing information search processing can be reduced. In the above-described second embodiment, the address control table storage units are provided corresponding to the divided address information of each hierarchy.
However, the address control table corresponding to the divided address information being referred to may be read.

Embodiment 3 Embodiment 3 of the present invention
In the first or second embodiment described above, the limited address control unit that performs the routing information search using the limited address control table including the upper division address information, the address mask, and the routing information or the pointer to the routing information is described. It is provided. FIG.
FIG. 4 is a diagram showing a schematic configuration of a communication network device 3 according to a third embodiment of the present invention. The basic configuration is the same as in the first and second embodiments. The same parts as those in FIG. 1 are denoted by the same reference numerals, and the description thereof will be omitted. Only different parts will be described here.

The communication network device 3 includes a limited address control unit 36 provided commonly to each layer of the divided address information. Further, instead of the first address control unit 11 to the third address control unit 13 and the routing information unit 15 of the first embodiment, the first address control unit 11 has the same function as the first address control unit 11, and the limited address control unit 36 The first address control unit 31 having the highest-order address control table capable of setting a pointer to the address control table, and the same functions as the second address control unit 12 and the limited address of the limited address control unit 36 A second address control unit 32 having a second address control table capable of setting a pointer to a control table, and having the same function as the third address control unit 13 and a limited address control unit 36 A third address control table that can set a pointer to the table It includes an address control unit 33, a retrieval control unit 30 that includes a routing information portion 35 having a routing information table is referred to by these address control table.

The first to third address control units 31 to 33 output a pointer to the limited address control table set in the address control table to the limited address control unit 36. The limited address control unit 36 receiving the pointer performs a routing information search process using the limited address control table. FIG. 7 is a diagram illustrating a configuration of the first to third address control tables D31 to D33 according to the third embodiment. The first address control table D31 is an uppermost address control table, and is the first address control table D of the first embodiment.
11 instead of the 11 search flag area D112,
It includes a search flag area D312 in which any one of the search flags “search end”, “continue search”, and “limit” is set. Here, when the search flag is “limited”, it indicates that the limited address control table is to be referred to.

The first address control table D31
Are the root flag area D113 and the next table pointer area D in the first address control table D11 of the first embodiment.
Instead of the routing pointer area D114, the root flag area D313, the next table pointer area D314, the routing pointer area D315,
Contains. Root flag area D313, next table pointer area D314, routing pointer area D31
5 includes the first address control table D1 of the first embodiment.
The same settings are made for the root flag area D113, the next table pointer area D114, and the routing pointer area D115 of No. 1. However, the search flag area D3
12 is set to “limit”, the next table pointer area D31 corresponding to the search flag area D312
4, a pointer indicating the position of a predetermined block in the limited address control table is set.

Similarly, the second address control table D32 and the third address control table D33 of the first embodiment are also used for the second address control table D32 and the third address control table D33.
3 has the same configuration as that of the route flag region D123, the next table pointer region D124, the routing pointer region D125, the route flag region D133, the next table pointer region D134, and the routing pointer region D135.
In place of these, the same route flag area D323,
Next table pointer area D324, routing pointer area D325, root flag area D333, next table pointer area D334, routing pointer area D33
5 is included.

The search flag areas D122 and D132
, A search flag area D322 or D332 in which any one of the search flags of “invalid”, “end of search”, “continuation of search”, and “limitation” is set. When “limit” is set in the search flag areas D322 and D332, the next table pointer areas D324 and D334 corresponding to the search flag areas D322 and D332 include:
A pointer indicating the position of a predetermined block in the limited address control table is set.

FIG. 8 is a diagram showing the configuration of the limited address control table D34 according to the third embodiment. The limited address control table D34 is configured for each block,
Data corresponding to up to four upper division address information is stored in the block. These blocks are provided by the number of “limits” set in the address control table. That is, the limited address control unit 36 searches up to four entries in one search process for one address. The number of upper division address information of one block is not particularly limited, and may be any number.

The limited address control table D34 includes an upper division address information area D343 for storing each upper division address information, an address mask area D344 for storing an address mask, and a routing pointer area D345 for storing a routing information table pointer. It includes a route flag area D346 in which a route flag similar to that in the address control table is set, and an entry flag area D342 storing an entry flag indicating whether the information is valid information. The data of each area is set in accordance with each upper division address information.

FIG. 9 is a diagram showing a configuration of the routing information table D35 according to the third embodiment. The routing information table D35 has the same configuration as the routing information table D15 of the first embodiment, and has a valid flag area D152 and a transmission interface area D of the first embodiment.
In place of 153, a similar valid flag area D352 and a transmission interface area D353 are included. Valid flag area D352, transmission interface area D353
Are the same as the valid flag area D152 and the transmission interface area D153 of the first embodiment, and each address control table and limited address control table D3
It is referenced using the routing information table pointer set to "4".

In the above configuration, the operation of the third embodiment will be described with reference to the flowchart of FIG.
FIG. 10 is a flowchart illustrating the flow of the operation of the search control unit 30 according to the third embodiment. The basic operation is the same as in the first and second embodiments, and the same parts as those in FIG. 4 are denoted by the same reference numerals and the description thereof will be omitted, and only different parts will be described here.

In the operation of the search control section 30, after the processing of step S1, it is determined whether or not the search flag stored at the position corresponding to the divided address information referred to is "continue" (S31). ). If the search flag is not “continue”, the process proceeds to step S2, and if the search flag is “continue”, the predetermined address of the limited address control table D34 indicated by the pointer stored at the position corresponding to the divided address information (S3)
2). Then, it is determined whether or not the upper division address information corresponding to the referenced address information is set in the block (S33). Specifically, the logical product of the address mask and the address information is calculated, and the calculated product is added to the upper division address information (if the upper division address information is shorter than the address information, 0 is added to the lower part and the same length is added) The comparison is made with the above.

If upper block address information corresponding to the referenced address information is set in the block, the process proceeds to step S4 by referring to the route flag corresponding to the upper block address information. Here, the upper division address information corresponding to the referred address information is determined by the longest match of the address mask. That is, if the address information multiplied by the address mask corresponds to a plurality of upper division address information, the longest upper division address information is selected. On the other hand, if the upper division address information corresponding to the address information being referred to is not set in the block, n
Returning to the address control table, referring to the route flag stored at the position corresponding to the divided address information being referred to (S34), and proceeding to step S4.

Next, a specific IP address will be described as an example. Here, examples of Cases 6 to 9 are shown in addition to Cases 1 to 5 described in Embodiment 1. Upper division address information "134.200.128.
80 "and the address mask" 255.255.255.2 "
IP address “134.200.12” corresponding to “55”
The routing information search result of “8.80” is “transmission interface E”. The routing information search result of the IP address “134.200.128.81” corresponding to the upper division address information “134.200.128.81” and the address mask “255.255.255.255” is “transmission interface F”.
This is referred to as Case 7.

The upper division address information "134.200.
100.82 "and address mask" 255.255.2 "
IP address “134.20” corresponding to “55.255”
The routing information search result of “0.128.82” is “transmission interface G”.
The IP address “134.200.x2.x1” corresponding to the upper division address information “134.200” and the address mask “255.255.0.0” (however, the IP address “134.200.128.80”, "134.2
00.128.81 "," 134.200.128.8 "
The routing information search result (except for “2”) is “transmission interface H”.

In the first address control table D31, "search end" is set in the search flag area D312 and "discard" is set in the root flag D313 at all positions other than the positions indicated by the pointers Aa133 and Aa134. Then, "invalid" is set in the next table pointer area D314, and the routing pointer area D315 is set.
Is set to “invalid”. In the second address control table D32, the search flag area D322, the root flag area D323, the next table pointer area D324, and the routing pointer area D325 are located at all positions other than the position indicated by the pointer Ba141.
Is set to “invalid”.

In the third address control table D33, the search flag area D332, the root flag area D333, and the next table pointer area D3 are set at all positions other than the positions indicated by the pointers Ca076 and Ca077.
34, it is assumed that "invalid" is set in the routing pointer area D335. 4 (not shown)
In the fourth address control table, “invalid” is set in all areas.

(Case 1, Case 2) IP address “1
33.141.77.59 "and the IP address" 133.
In the case 1 and the case 2 in which the processing of the packet having the destination of “141.77.60” is performed, first, the address search request unit 16 transmits the address information to the search control unit 30 to request the address search. In the search control unit 30 receiving this request, the first address control unit 31 uses the uppermost divided address information “133” and stores the data stored at the position indicated by the pointer Aa 133 in the first address control table D31. (Search flag, etc.). And
Since “search continuation” is set in the search flag area D312, the pointer Ba000 indicated in the next table pointer area D314 is acquired, and the pointer Ba000 is set to the second
The address is sent to the address control unit 32.

The second address control unit 32, having received the pointer Ba000, sets the second divided address information “14”.
Using "1", the second address control table D32 refers to the data (search flag and the like) stored at the position indicated by the pointer Ba141 in the block indicated by the pointer Ba000. Since “search continuation” is set in the search flag area D322, the pointer Ca000 indicated in the next table pointer area D324 at that position is acquired, and the pointer Ca000 is sent to the third address control unit 33.

The third address control unit 33, having received the pointer Ca000, sets the third divided address information "77"
And in the third address control table D33,
Pointer C in the block indicated by pointer Ca000
Reference is made to data (search flag, etc.) stored at the position indicated by a077. Then, the search flag area D3
Since “limitation” is set to 32, the pointer Ka0 indicated in the next table pointer area D334 is obtained,
The pointer Ka0 is sent to the limited address control unit 36.

The limited address control unit 36 having received the pointer Ka0 refers to the block indicated by the pointer Ka0 (the position indicated by the pointers Ka0 to Ka3). Then, using the upper division address information stored in the upper division address information area D343 and the address mask stored in the address mask area D344 at the positions indicated by the pointers Ka0 and Ka1 whose entry flags are "valid", The information is multiplied by these address masks, and it is determined whether or not the information matches the upper division address information.

When the IP address is "133.141.77.
In the case of "59", the result of multiplying this address information by the address mask "255.255.255.255" of the address mask area D344 at the position indicated by the pointer Ka0 is the upper division of the upper division address information area D343 at that position. Since the address information matches the address information "133.141.77.59", the route flag in the route flag area D346 at that position is referred to. Since the root flag is "block", the routing pointer area D3
The routing information table pointer D indicated by 45 is obtained, and the routing information table pointer D is sent to the routing information section 35.

The routing information section 35 having received the routing information table pointer D refers to the data (valid flag, etc.) stored in the routing information table D35 at the position indicated by the routing information table pointer D. Then, “valid” indicating that the transmission interface area D353 is valid is set in the valid flag area D352.
Is set, the transmission interface area D3
The transmission interface name “D” indicated by 53 is acquired, and the transmission interface name “D” is sent to the address search request unit 16. The address search request unit 16 that has received the transmission interface name “D” transmits a packet from the transmission interface D.

On the other hand, if the IP address is "133.141.
77.60 ", the pointer Ka is added to this address information.
1 is multiplied by the address mask “255.255.255.255” of the address mask area D344 at the position indicated by “1”.
3 upper division address information “133.141.77.6”
0 ”, the root flag area D3 at that position
Reference is made to 46 route flags. Since the route flag is "no route", the address search request unit 16 is notified that there is no route. The address search request unit 16 that has received the notification performs a process when there is no packet transmission route.

(Case 3) Next, the IP address “13”
3.141.76. Case 3 for processing a packet addressed to “x1” will be described. In case 3,
First, the address search request unit 16 transmits address information to the search control unit 30 and requests an address search. Upon receiving the request, the search control unit 30 sets the first address control unit 3
1 uses the highest division address information “133”,
Pointer Aa133 of first address control table D31
Refer to the data (search flag etc.) stored at the position indicated by. Then, since “search continuation” is set in the search flag area D312, the next table pointer area D
The pointer Ba000 indicated by 314 is acquired, and the pointer Ba000 is sent to the second address control unit 32.

The second address control unit 32, having received the pointer Ba000, sets the second divided address information “14”.
Using "1", the data (search flag or the like) stored at the position indicated by the pointer Ba141 in the block indicated by the pointer Ba000 is referred to in the second address control table D32. Then, the search flag area D32
Since “continuation of search” is set to 2, the pointer Ca000 indicated in the next table pointer area D324 is obtained, and the pointer Ca000 is sent to the third address control unit 33.

The third address control unit 33, having received the pointer Ca000, sets the third divided address information “76”.
And in the third address control table D33,
Pointer C in the block indicated by pointer Ca000
Reference is made to data (search flag and the like) stored at the position indicated by a076. Since "search end" is set in the search flag area D332 and "block" is set in the root flag area D333, the routing information table pointer C indicated in the routing pointer area D335 is acquired, and the routing information table is obtained. The pointer C is sent to the routing information section 35.

Upon receiving the routing information table pointer C, the routing information section 35 refers to the data (valid flag, etc.) stored in the routing information table D35 at the position indicated by the routing information table pointer C. Since “valid” is set in the valid flag area D352, the transmission interface name “C” indicated in the transmission interface area D353 is acquired, and the transmission interface name “C” is sent to the address search request unit 16. The address search request unit 16 that has received the transmission interface name “C” transmits a packet from the transmission interface C.

The IP address "133.141.7"
7. x1 ”(however, the IP address“ 133.141.
77.59 "and" 133.141.77.60 "), the address search request unit 16 first sends the address information to the search control unit 30 to perform the address search. Request. In the search control unit 30 receiving this request, the first address control unit 31 uses the uppermost divided address information “133” and stores the data stored at the position indicated by the pointer Aa 133 in the first address control table D31. (Search flag, etc.). Since “continue search” is set in the search flag area D112, the next table pointer area D314
And obtains the pointer Ba000 indicated by
000 to the second address control unit 32.

Upon receiving the pointer Ba000, the second address control unit 32 sets the second divided address information “14”.
Using "1", the data (search flag or the like) stored at the position indicated by the pointer Ba141 in the block indicated by the pointer Ba000 is referred to in the second address control table D32. Then, the search flag area D32
Since “continuation of search” is set to 2, the pointer Ca000 indicated in the next table pointer area D324 is obtained, and the pointer Ca000 is sent to the third address control unit 33.

The third address control unit 33, having received the pointer Ca000, sets the third divided address information “77”.
And in the third address control table D33,
Pointer C in the block indicated by pointer Ca000
Reference is made to data (search flag, etc.) stored at the position indicated by a077. Since “limit” is set in the search flag area D332, the pointer Ka0 indicated in the next table pointer area D334 is obtained, and the pointer Ka0 is sent to the limited address control unit 36.

The limited address control unit 36 having received the pointer Ka0 refers to the block indicated by the pointer Ka0 (the position indicated by the pointers Ka0 to Ka3). Then, using the upper division address information stored in the upper division address information area D343 and the address mask stored in the address mask area D344 at the positions indicated by the pointers Ka0 and Ka1 whose entry flags are "valid", The information is multiplied by these address masks, and it is determined whether or not the information matches the upper division address information.

The IP address “133.141.77.x”
1 "(however, the IP address" 133.141.77.
59 "and" 133.141.77.60 "), since the corresponding limited address information is not set, the process returns to the third address control table D33, and the root flag area D333 at the position indicated by the pointer Ca077.
And the routing pointer area D335. Since "block" is set in the root flag area D333, the routing information table pointer C indicated in the routing pointer area D335 is obtained, and the routing information table pointer C is stored in the routing information section 3.
Send to 5.

Upon receiving the routing information table pointer C, the routing information section 35 refers to the data (valid flag, etc.) stored in the routing information table D35 at the position indicated by the routing information table pointer C. Since “valid” is set in the valid flag area D352, the transmission interface name “C” indicated in the transmission interface area D353 is acquired, and the transmission interface name “C” is sent to the address search request unit 16. The address search request unit 16 that has received the transmission interface name “C” transmits a packet from the transmission interface C.

As described above, Embodiments 1 and 2
Similarly, the “block” is stored in the root flag area D333 of the pointer Ca077 of the third address control table D33.
Is set, the upper division address information “133.14” is set.
1.77 other upper division address information (other upper division address information generated by adding lower bits to one upper division address information, for example, "133.1"
41.77.10 "), only the portion corresponding to the bit to be added (for example," 10 ") needs to be changed, and it corresponds to the already set upper division address information. Does not affect parts.
Similar effects can be obtained by setting "blocks" for other address control tables.

(Cases 6 to 9) Cases 4 and 5 are the same as those in the first and second embodiments, and a description thereof will be omitted. Next, cases 6 to 9 will be described. IP address "134.200.12
8.80 "," 134.200.128.81 "," 1
34.200.128.82 "," 134.200.x
2. In the processing of a packet addressed to “x1”, first, the address search request unit 16 transmits address information to the search control unit 30 and requests an address search.

In the search control unit 30 receiving this request, the first address control unit 31 uses the uppermost divided address information "134" and uses the first address control table D31.
(A search flag or the like) stored at the position indicated by the pointer Aa134 of FIG. Since "limit" is set in the search flag area D312, the pointer Kb0 indicated in the next table pointer area D314 is acquired, and the pointer Kb0 is set to the limited address control table 34.
Send to

The limited address control unit 36 which has received the pointer Kb0 refers to the block indicated by the pointer Kb0 (the position indicated by the pointers Kb0 to Kb3). Then, using the upper division address information stored in the upper division address information area D343 and the address mask stored in the address mask area D344 at the position indicated by the pointers Kb0 to Kb3 whose entry flags are “valid”, The information is multiplied by these address masks, and it is determined whether or not the information matches the upper division address information.

When the IP address is "134.200.12"
In the case of “8.80”, the pointer Kb0 is added to this address information.
The result obtained by multiplying the address mask area D344 at the position indicated by マ ス ク by the address mask “255.255.255.255” is the upper division address information area D343 at that position.
Upper division address information “134.200.128.8”
0 ". Further, the address mask “25” of the address mask area D344 at the position indicated by the pointer Kb3
The result obtained by multiplying “5.255.0.0” matches the higher-order address information “134.200” in the upper-order address information area D343 at that position.

As described above, when the result of multiplying the address information by the address mask matches a plurality of upper division address information, the limited address control unit 36 makes the unmasked portion longer according to the longest match of the address mask. Choose one. In this case, the upper division address information “134.200.128.80” is selected. Then, the upper division address information “134.200.128.
80, and the root flag is “block”. Therefore, the routing information table pointer E indicated in the routing pointer area D345 is obtained, and the routing information table pointer E is stored in the routing information section 35. send.

Upon receiving the routing information table pointer E, the routing information section 35 refers to the data (valid flag, etc.) stored in the routing information table D35 at the position indicated by the routing information table pointer E. Then, “valid” indicating that the transmission interface area D353 is valid is set in the valid flag area D352.
Is set, the transmission interface area D3
The transmission interface name “E” indicated by 53 is acquired, and the transmission interface name “E” is sent to the address search request unit 16. The address search request unit 16 that has received the transmission interface name “E” transmits a packet from the transmission interface E.

When the IP address is "134.200.
128.81 ", the same processing is performed, and the packet is transmitted from the transmission interface F. Also, IP
The same processing is performed when the address is “134.200.128.82”, but the validity flag of the routing information table D35 (at the position indicated by the routing information table pointer G) referred to by the routing information unit 35 is set to “ Since it is “invalid”, the routing information unit 35 replies to the address search request unit 16 that there is no route.

The IP address “134.200.x”
2. x1 ”(IP address“ 134.200.128.
80 "," 134.200.128.81 "," 13
4.200.128.82 ”), the same processing is performed, but the corresponding upper-level divided address information is“ 1 ”.
34.200 ", the longest match processing of the address mask is not performed, and the packet is transmitted from the transmission interface H.

As described above, according to the third embodiment,
Limited address control table D in limited address control unit 36
Since the longest match processing of the address mask in the address search is controlled by the N.34, it is necessary to register a large number of entries, and when the upper division address information and the address mask of the entry to be registered take various combinations. Even if there is, there is an effect that the storage capacity for each address control table is kept small.

Further, since the routing information table D35 indicates the validity or invalidity of the stored information, even if the information indicated by the transmission interface D353 obtained as a retrieval result becomes unavailable temporarily. Therefore, without updating each address control table and the limited address control table D34, only by updating the valid flag area D352 of the routing information table D35, it is possible to perform a process without a route and to reduce the load of updating the table. is there.

In the above-described third embodiment, the limited address control table D3 is provided in the limited address control unit 36.
4, but various methods can be used to store the limited address control table D34. For example, if a normal dynamic RAM is used, the limited address control table D34 can be referred to at a high speed, so that the limited address control unit 36 can increase the number of entries searched at one time, and can reduce many entries. There is an effect that a high-speed search can be performed with a storage capacity.

In the third embodiment, the search using the IP address has been described as an example. However, another address having a different address length may be used. It may be changed in accordance with the above, and a similar effect can be obtained. Although the search using the IP address has been described as an example, the search may be performed using other information, or the search may be performed by combining the address and other information, and the same effect is obtained. . For example, the same applies to a case where 5-byte information, which is a combination of an IP address and 1-byte information for traffic control, is used as address information, and this address information is divided into five pieces of divided address information for each byte and searched. And the same effect can be obtained.

In the limited address range,
Since the longest match processing of the address mask is controlled for each of a small number of registered entries, it is necessary to register a large number of entries, and when the upper division address information and the address mask of the entry to be registered take various combinations. However, there is an effect that the storage capacity of information is reduced for address search.

Embodiment 4 Embodiment 4 of the present invention
In the first to third embodiments described above, a plurality of lengths of divided address information can be set, and these address information can be divided into different lengths according to each address information. It is. FIG.
FIG. 4 is a diagram showing a schematic configuration of a communication network device 4 according to a fourth embodiment of the present invention. Note that the basic configuration is the same as in the first to third embodiments, and the same parts as those in FIG. 6 are denoted by the same reference numerals and description thereof will be omitted, and only different parts will be described here.

The communication network device 4 according to the third embodiment
The first address control unit 31 and the second address control unit 32 have the same functions as those described above, and the position of the divided address information in the address information (from what bit to what bit is divided). A) a search control unit 40 including a first address control unit 41 and an second address control unit 42 having an address control table including information indicating the above. FIG. 12 shows a first address control table D41 stored in the first address control unit 41 and a second address control table D42 stored in the second address control unit 42.
FIG. 3 is a diagram showing the configuration of FIG.

The first address control table D41 contains 0 to
The search flag area D412, the root flag area D413, the next table pointer area D414, the routing pointer area D415, the start bit position area D416, and the bit length area D417 are provided for each of the uppermost 255 pieces of divided address information. Contains. Similarly, the second address control table D42 includes a search flag area D422, a root flag area D423, and a next table pointer area D42 for each of the second divided address information from 0 to 255.
4, a routing pointer area D425, a start bit position area D426, and a bit length area D427.

Search flag area D412, root flag area D413, next table pointer area D414, routing pointer area D415, search flag area D422,
Root flag area D423, next table pointer area D
424, the routing pointer area D425 are the search flag area D312, the root flag area D313, and the next table pointer area D314, respectively, of the third embodiment.
Routing pointer area D315, search flag area D3
22, the root flag area D323, the next table pointer area D324, and the routing pointer area D325.

Start bit position area D416, D426
Stores the start bit position of divided address information used by the lower address control unit (information indicating from which bit of the address information the bit is divided). Bit length area D41
7, D427 stores the bit length (information indicating how many bits are divided from the start bit position) of the divided address information used in the lower address control unit.

In the above configuration, the operation of the fourth embodiment will be described. In the operation of the fourth embodiment, the address search request unit 16 transmits address information to the search control unit 40 and requests an address search. In the search control unit 40 receiving this request, the first address control unit 41 performs a search using the highest-order divided address information in the same manner as in the first to third embodiments. For example, if the highest division address information is “133”, the first address control unit 41 refers to the position indicated by the pointer Aa133. Then, since “search continuation” is set in the search flag area D412, the next table pointer area D
The pointer Ba0 indicated at 414, “9” indicated at the start bit position area D416, and the bit length area D417
Is acquired.

For example, the value of the divided address information obtained by dividing 2 bits from the ninth bit of the address information is “2” (1
(0-base number), the second address control unit 42
The position indicated by the pointer Ba2 in the second address control table D42 is referred to using the value of “2”. Since “search continuation” is set in the search flag area D422, the pointer Ca0 indicated in the next table pointer D424, “11” indicated in the start bit position area D426, and the pointer Ca0 indicated in the bit length area D427 are indicated. "1
0 ”is obtained. As described above, the start bit position and the bit length are sequentially obtained, and the lower address control table is referred to.

For example, when the highest division address information is “134”, the first address control unit 41
Refers to the position indicated by the pointer Aa134. Since “search continuation” is set in the search flag area D412, the pointer Bb0 indicated in the next table pointer area D414, “9” indicated in the start bit position area D416, and the bit length area D417 The indicated "3" is obtained. For example, if the value of the divided address information obtained by dividing 3 bits from the ninth bit of the address information is “7” (decimal number), the second address control unit 42 uses the value of “7” , The position indicated by the pointer Bb7 in the second address control table D42. Then, since “continuation of search” is set in the search flag area D422, the next table pointer D42
4 and a start bit position area D
“12” indicated in 426 and “12” indicated in the bit length area D427 are acquired. As described above, the start bit position and the bit length are sequentially obtained, and the lower address control table is referred to.

In this example, the divided address information having different bit lengths is associated with one address control table. However, an address control table may be provided for each bit length. Other operations are the same as those of the first to third embodiments.

As described above, according to the fourth embodiment,
Since the search is performed according to the number of bits required for the search, even if the content of the search target is different when performing an address search of a different protocol, only the table settings should be set according to the protocol. Since the address search of different protocols is commonly performed by one search control unit, the effect that the search circuit can be reduced can be obtained.

Embodiment 5 FIG. Embodiment 5 of the present invention
In the first to fourth embodiments, each address control unit, limited address control unit, and routing information unit execute pipeline processing. FIG. 13 is a diagram illustrating a schematic configuration of the communication network device 5 according to the fifth embodiment of the present invention. The communication network device 5 has the same configuration as the communication network device 4 of the fourth embodiment, but the first address control unit 4
1, second address control unit 42, third address control unit 3
3, a fourth address control unit 14, a routing information unit 15,
Instead of the limited address control unit 36, a first address control unit 51, a second address control unit 52, a third address control unit 53, and a fourth address control unit 5 that execute pipeline processing
4, a search control unit 50 having a routing information unit 55 and a limited address control unit 56.

First address control unit 51, second address control unit 52, third address control unit 53, fourth address control unit 54, routing information unit 55, limited address control unit 5
6, the first address control unit 41, the second address control unit 42, the third address control unit 33, the fourth address control unit 14, the routing information unit 15, the limited address control of the fourth embodiment. Processing similar to that of the unit 36 is performed by pipeline processing. That is, in each of these units, the routing information search processing using the address information of the different packet is simultaneously executed.

In the above configuration, the operation of the fifth embodiment will be described with reference to the flowchart of FIG.
FIG. 14 is a flowchart illustrating the flow of the operation of the communication network device 5 according to the fifth embodiment. The communication network device 5 receives the search request (S51),
Pipeline first stage processing (S52), pipeline second stage processing (S53), pipeline third stage processing (S5)
4), the fourth stage of the pipeline processing (S55), the fifth stage of the pipeline processing (S56), and the notification of the search result (S57) are sequentially performed. The fifth stage processing of the pipeline in step S55 is performed by the fourth address control unit 5 in the fourth stage of the pipeline.
4 and the search process performed by the limited address control unit 56 at the fourth stage of the pipeline (S553).
And a process (S551) of determining whether the fourth address control unit 54 performs the search process or the limited address control unit 56 performs the search process in the fourth stage of the pipeline.

The first-stage pipeline processing in step S52 is processing performed by the first address control unit 51, and the second-stage pipeline processing in step S53 is processing performed by the second address control unit 52. The pipeline third stage processing of S54 is processing performed by the third address control unit 53, and the pipeline fourth stage processing of step S55 is
Fourth address control unit 54 or limited address control unit 56
, And the fifth-stage pipeline processing in step S56 is processing performed by the routing information unit 55.

In the following, it is assumed that there are five IP packets to be processed.
Processing of these IP packets will be specifically described as PB, IPC, IPD, and IPE. The IP packets IPA, IPB, IPC, IPD, and IPE are processed in the first-stage pipeline processing (S52), are then processed in the second-stage pipeline processing (S53), and then are processed in the third-stage pipeline (S52). The processing is performed in S54), then the processing is performed in the fourth stage processing of the pipeline (S55), and then the processing is performed in the fifth processing of the pipeline (S56).

When the search control unit 50 processes the packet IPA in the first-stage pipeline processing (S52), it receives a request to search for the packet IPB and processes the packet IPB in the first-stage pipeline processing (S52). When a packet IPC search request is received and the packet IPC is processed in the first stage of the pipeline processing (S52), the packet IC
When the PD search request is received and the packet IPD is processed in the first-stage pipeline processing (S52), the packet IPD
When the search request of E is received, when processing the packet IPA in the fifth stage of pipeline (S56), the packet IPB is processed in the fourth stage of pipeline (S55), and the packet IPC is processed in the third stage of pipeline. Processing (S5
4), the packet IPD is processed by the second-stage pipeline processing (S53), and the packet IPE is processed by the first-stage pipeline processing (S52).

That is, as shown in FIG. 15, when the address control units 51 to 54, the routing information unit 55, and the limited address control unit 56 complete their own routing information search processing for one packet, the entire routing information Without waiting for the search process to end, the device performs its own routing information search process for the next packet. As a result, routing information search processing for different packets is performed simultaneously.

For example, in case 6 described above, in the first stage of the pipeline processing (S52), a search result is obtained that "the limited address control unit 56 performs a search process using the pointer Kb0." In this case, the second stage processing of the pipeline (S53) and the third stage processing of the pipeline (S54) only transmit the search result.
In the pipeline fourth stage process (S55), the limited address control unit 56 performs a search process (S553).

As described above, according to the fifth embodiment,
Each address control unit is independent for each divided address information, and the limited address control unit 55 also includes the address control units 51 to 5.
4, the address control units 51 to 54 and the limited address control unit 55 for processing the respective divided address information perform the address search of the different packets by pipeline processing. The number of IP packets that can be processed, that is, the speed of address search processing can be improved.

Embodiment 6 FIG. Embodiment 6 of the present invention
In the first to fifth embodiments, a plurality of search control units are provided, and each of them searches for routing information. FIG. 16 is a diagram illustrating a schematic configuration of the communication network device 6 according to the sixth embodiment of the present invention. The communication network device 6 according to the fifth embodiment
Search control unit 60 including a plurality of search control units similar to
And an address search requesting unit 63 that transmits address information of the packet to the complex search control unit 60 and requests a search for routing information.

The address search request section 63 transmits a plurality of pieces of address information included in the packet to the composite search control section 60. The plurality of pieces of address information may be, for example, a plurality of types of information such as a transmission destination address and a transmission source address, or one type of information (such as an IP address) may be divided into a plurality (upper, lower, etc.). It may be something. The composite search control unit 60 has a search control unit corresponding to each of the plurality of pieces of address information. The number of search control units is not particularly limited, and may be any number.
The compound search control unit 60 includes the first search control unit 61 and the second search control unit 61.
It is assumed that two search control units of the search control unit 62 are provided.

First search control section 61, second search control section 62
Has the same function as the search control unit 50 of the fifth embodiment, and searches for routing information using different address information. First search control unit 61, second search control unit 6
2 independently performs each search process and returns each search result to the address search request unit 63. Also,
A search control unit may be connected in series to search for routing information in which a plurality of addresses are associated.
That is, the first search control unit 61 and the second search control unit 62 are connected in series, and the search result of the first search control unit 61 is output to the second search control unit 62. A search process according to the search result of the search control unit 61 may be performed.

FIG. 17 is a diagram showing a configuration of the routing information table D6 of the first search control unit 61 according to the sixth embodiment. The routing information table D6 has the same configuration as the routing information table D35 of the fifth embodiment, but further includes a next search control unit (second search control unit 62).
And includes a next table pointer area D61 for designating a pointer to be used for the search processing. First search control unit 6
1 sends the pointer and the transmission interface name as a search result to the second search control unit 62, and the second search control unit 62 searches by referring to the address control table corresponding to the pointer from the first search control unit 61. Perform processing.

In the above configuration, the operation of the sixth embodiment will be described with reference to the flowchart of FIG. FIG. 18 shows a composite search control unit 6 according to the sixth embodiment.
FIG. 9 is a diagram for explaining an operation of a zero. In the operation of the sixth embodiment, first, the address search request unit 63 transmits address information to the complex search control unit 60, and requests an address search. In the combined search control unit 60 that has received this request, the first search control unit 61 refers to, for example, the address information of the source address of the address information from the combined search control unit 60, and performs the processing according to the fifth embodiment. A similar routing information search process is performed. Then, the search result is transmitted to the second search control unit 62 (S61).

The second search control unit 62 that has received the search result from the first search control unit 61 refers to, for example, the address information of the transmission destination address in the address information from the compound search control unit 60, and (1) Based on the search result from the search control unit 61, the same search processing of the routing information as in the fifth embodiment is performed. Then, the search result is transmitted to the address search request unit 63 (S61). Other operations are the same as those in the first to fifth embodiments.

As described above, according to the sixth embodiment,
A plurality of search control units constitute the complex search control unit 60, and the routing information acquired by each search control unit includes a pointer of the address control table used by the next search control unit. Even if the addresses searched by the sections are different, each search control section can perform a longest match process of the address mask for the address portion to be processed, and obtain a search result in which all the search target addresses are associated with each other. effective. Further, other information may be used in place of the address, and further, the address and other information may be combined and used as the address information. In this case, the same effect can be obtained.

A computer program for realizing the routing information search method according to the first to sixth embodiments is stored on a magnetic disk such as a floppy disk, ROM, EPROM, EEPROM, flash ROM, or the like.
It is stored in a portable recording medium such as a semiconductor memory such as an OM (including a built-in cartridge or a PC card), an optical disk such as a CD-ROM and a DVD, and a magneto-optical disk such as an MO. The program recorded on the medium is stored in a ROM, RA
By installing it on a fixed recording medium such as a hard disk or a hard disk, the routing information search device can be provided with a function of executing the above-described routing information search method.

Also, this program is used for LAN, WA
N, via a network such as the Internet,
The transmitted program may be installed on a fixed recording medium of the routing information search device. Further, this program is not necessarily limited to a single program, and may be distributed as a plurality of modules or libraries, or may achieve its function in cooperation with a separate program such as an OS. It may be.

[0202]

As described above, according to the present invention, the first address information is provided in the form of a tree in which the first address information is provided in a tree shape corresponding to each layer of the divided address information obtained by hierarchically dividing the predetermined number of bits. , And each of the first search control information indicates, for each of the divided address information of its own hierarchy, which of the combined address information obtained by combining the divided address information to the highest-order divided address information If the second address information matches a part of the second address information cut out from the top, the information includes information used for referring to the lower first search control information, and includes all of the combination address information or the lowest of the combination address information. If a part of the divided address information is truncated from the above and matches any one of the second address information, the information used for referring to the lower first search control information is changed. Regardless suck whether, including information used to refer to the routing information or the routing information corresponding to the second address information. As a result, all of the certain second address information coincides with a part of the other second address information cut out from the top.
That is, even in the case of the inclusion relationship, it is not necessary to set a large amount of routing information corresponding to the shorter second address information, so that the time required for the setting process and the setting change process is reduced, and The effect is that the load can be reduced and the cost can be reduced.

According to the next invention, valid information indicating whether each piece of routing information is valid or invalid is stored.
As a result, the routing information can be easily invalidated, and the invalidated routing information can be easily validated. Therefore, the time required for the setting process and the setting change process can be further reduced, and the setting process and the There is an effect that the load of the setting change processing can be further reduced, and the cost can be further reduced.

According to the next invention, the second address information, the network mask corresponding to the second address information, the routing information corresponding to the second address information, or the information used for referring to the routing information When,
Is stored, and the first search control information includes, for each of the divided address information of its own hierarchy, the combined address information obtained by combining from the divided address information to the highest divided address information. Everything is any second
If the address information matches a part of the address information extracted from the top, the information includes information used for referring to the second search control information or information used for referring to the lower first search control information. Thereby, since the data amount of the first search control information can be reduced, there is an effect that the total data amount can be reduced and the cost can be further reduced.

According to the next invention, the first search control information includes information indicating which part of the first address information each divided address information of its own hierarchy is divided. This makes it possible to deal with addresses of a plurality of types of protocols. By preparing first search control information corresponding to each protocol, it is possible to process addresses of a plurality of types of protocols with one routing information search device. Therefore, there is an effect that the circuit scale can be reduced and the cost can be further reduced.

According to the next invention, in order to search for routing information corresponding to each of a plurality of first address information included in one piece of processing data, a plurality of pieces of first address information are included in one piece of processing data. In this case, it is possible to search for routing information corresponding to each first address information.

[0207] According to the next invention, the lower search means acquires the information on the search result from the upper search means and searches for the routing information based on the information on the search result. Thus, it is possible to obtain a search result in which a plurality of pieces of first address information are associated with each other.

According to the next invention, since a plurality of hierarchical search means search for routing information in each hierarchy by pipeline processing, the search processing can be speeded up.

[0209] According to the next invention, the routing information retrieval control data is provided in a tree-like manner in which the first address information is provided in a tree-like manner in correspondence with each layer of the divided address information obtained by hierarchically dividing the first address information by a predetermined number of bits. 1 search control information, and the first search control information is, for each divided address information of its own hierarchy, any one of the combined address information obtained by combining from the divided address information to the uppermost divided address information. Contains the information used to refer to the lower first search control information when the second address information is partially cut out from the top of the second address information. When a part of the divided address information is truncated and matches any of the second address information, the divided address information is used for referring to the lower first search control information. Regardless of whether it contains information, including the information used to refer to the routing information or the routing information corresponding to the second address information. As a result, even if all of the certain second address information matches a part of the other second address information cut out from the top, that is, even if the second address information has an inclusive relation, it is added to the shorter second address information. Since it is not necessary to set a lot of corresponding routing information, it is possible to shorten the time required for the setting process and the setting change process, to reduce the load of the setting process and the setting change process, and to reduce the cost. .

According to the next invention, the routing information search control data further includes routing information search control data including valid information indicating whether each routing information is valid or invalid. As a result, the routing information can be easily invalidated, and the invalidated routing information can be easily validated. Therefore, the time required for the setting process and the setting change process can be further reduced, and the setting process and the There is an effect that the load of the setting change processing can be further reduced, and the cost can be further reduced.

According to the next invention, the routing information search control data further includes second address information, a network mask corresponding to the second address information, and routing information corresponding to the second address information. Or information used for referring to the routing information.
Including search control information. Thereby, since the data amount of the first search control information can be reduced, the total data amount can be reduced, and the cost can be further reduced.
This has the effect.

According to the next invention, the first search control information includes information indicating which part of the first address information each divided address information of its own hierarchy is divided. Thereby, it is possible to correspond to the addresses of a plurality of types of protocols, and by preparing the first search control information corresponding to each protocol, it is possible to process the addresses of the plurality of types of protocols with one routing information search device. Therefore, there is an effect that the circuit scale can be reduced and the cost can be further reduced.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a schematic configuration of a communication network device according to a first embodiment of the present invention;

FIG. 2 is a diagram illustrating a configuration of an address control table according to the first embodiment;

FIG. 3 is a diagram showing a configuration of a routing information table according to the first exemplary embodiment;

FIG. 4 is a flowchart illustrating a flow of an operation of a search control unit according to the first exemplary embodiment;

FIG. 5 is a diagram illustrating a schematic configuration of a communication network device according to a second embodiment of the present invention;

FIG. 6 is a diagram illustrating a schematic configuration of a communication network device according to a third embodiment of the present invention;

FIG. 7 is a diagram illustrating a configuration of an address control table according to a third embodiment;

FIG. 8 is a diagram illustrating a configuration of a limited address control table according to a third embodiment;

FIG. 9 is a diagram illustrating a configuration of a routing information table according to the third embodiment;

FIG. 10 is a flowchart illustrating an operation flow of a search control unit according to the third embodiment;

FIG. 11 is a diagram illustrating a schematic configuration of a communication network device according to a fourth embodiment of the present invention;

FIG. 12 is a diagram illustrating a configuration of an address control table according to a fourth embodiment;

FIG. 13 is a diagram showing a schematic configuration of a communication network device according to a fifth embodiment of the present invention.

FIG. 14 is a flowchart illustrating a flow of an operation of the communication network device according to the fifth embodiment;

FIG. 15 is a diagram for explaining an operation of a search control unit according to the fifth embodiment;

FIG. 16 is a diagram illustrating a schematic configuration of a communication network device according to a sixth embodiment of the present invention.

FIG. 17 is a diagram illustrating a configuration of a routing information table according to the sixth embodiment;

FIG. 18 is a diagram for explaining an operation of the compound search control unit according to the sixth embodiment;

FIG. 19 is a diagram showing a configuration of a conventional address control table.

[Explanation of symbols]

1, 2, 3, 4, 5, 6 communication network device, 1
0, 20, 30, 40, 50 Search control unit, 11, 3
1,41,51 First address control unit, 12,32,4
2,52 second address control unit, 13,33,43,5
3 Third address control unit, 14, 54 Fourth address control unit, 15, 55 Routing information unit, 16, 63 Address search request unit, 21 First address control table storage unit, 22 Second address control table storage unit, 23 Third address control table storage unit, 24 Fourth address control table storage unit, 25 Address control units, 36, 56
Limited address control unit, 60 Compound search control unit, 61
First search control unit, 62 Second search control unit.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Naoyoshi Okazaki 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsui Electric Co., Ltd. (72) Teruko Fujii 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Within Mitsui Electric Co., Ltd. (72) Inventor Tetsuo Sadahaku 2-3-2 Marunouchi, Chiyoda-ku, Tokyo F-term (reference) 5B075 ND02 ND20 NK54 QM02 5K030 GA01 GA06 HA08 HD03 HD06 HD09 JA11 KA05 LD17 LE02 LE14 5K033 AA02 AA03 AA04 CB06 CB09 CB11 DA05 DB12 DB16 DB18 EC04

Claims (11)

[Claims] 1. A transmission route or processing content of the processing data according to second address information obtained by cutting out first address information included in processing data processed by a communication network device according to a plurality of network masks. A routing information search device that searches for routing information that indicates the first address information, wherein the first address information is provided in a tree shape corresponding to each layer of divided address information obtained by hierarchically dividing the first address information by a predetermined number of bits. A first storage unit storing the first search control information; and a search unit searching the routing information based on the first search control information stored in the first storage unit. The first search control information is, for each piece of divided address information of its own hierarchy, a combination address combining the divided address information and the highest-order divided address information. If all of the address information coincides with a part of any of the second address information cut out from the top, the information includes information used for referring to lower first search control information, and Alternatively, in the case where a part of the divided address information truncated from the lowest of the combination address information matches all of any of the second address information, information used for referring to the lower first search control information. Irrespective of whether or not the first address information is included, the information includes routing information corresponding to the second address information or information used for referring to the routing information. With reference to the divided address information and the first search control information, and the first search control information corresponds to the divided address information and the lower first search control information When the information used for information reference is included, the lower-level first search control information is referred to, and the lower-level first search control information corresponds to the division address information. If the routing information or the information used for referencing the routing information is not included in the information used for reference, the routing information is acquired, and the first search control information corresponds to the divided address information. The first search control information does not include the information used for referring to the first search control information and the routing information or the information used for referencing the routing information, and the first search control information of the higher order corresponds to the upper divided address information. Or a routing information search device for acquiring the routing information when the routing information includes information used for referring to the routing information. . And a second storage unit for storing valid information indicating whether each of the routing information is valid or invalid. The search unit is stored in the second storage unit. 2. The routing information search device according to claim 1, wherein the routing information is searched based on the valid information. 3. The second address information, a network mask corresponding to the second address information, routing information corresponding to the second address information, or information used for referring to the routing information, And third storage means for storing second search control information including the following. The first search control information is, for each divided address information of its own hierarchy, the highest divided address from the divided address information. If all of the combined address information obtained by combining up to the information matches a part of the second address information cut out from the top, the information used for referring to the second search control information or the lower order The search means includes information used for referring to first search control information, wherein the search means is configured such that the first search control information being referred to corresponds to the divided address information being referred to. When the information used for referring to the second search control information is included, the second search control information is referenced, and the network mask included in the second search control information is multiplied by the first address information being searched. 3. The device according to claim 1, wherein when the object corresponds to the second address information included in the second search control information, routing information corresponding to the second address information is obtained. 4. Routing information retrieval device. 4. The apparatus according to claim 1, wherein the first search control information includes information indicating which part of the first address information each divided address information of its own hierarchy is divided. The routing information search device according to 1, 2, or 3. 5. The processing data includes a plurality of pieces of the first address information for one piece of the processing data, and the search unit is provided in a plurality corresponding to the plurality of pieces of the first address information. The routing information search device according to claim 1, wherein the plurality of search units respectively search for corresponding routing information. 6. The plurality of search means are connected in series, and the lower search means obtains information on search results from an upper search means, and searches for routing information based on the information on the search results. 6. The method according to claim 5, wherein
A routing information search device according to claim 1. 7. The search means comprises a plurality of hierarchy search means provided for each hierarchy of the divided address information, wherein the plurality of hierarchy search means search for the routing information in each hierarchy by pipeline processing. The routing information search device according to claim 1, wherein the routing information search device performs a process. 8. A transmission route or processing content of the processing data according to second address information obtained by cutting out first address information included in processing data processed by a communication network device according to a plurality of network masks. A computer-readable recording medium storing routing information search control data used for routing information search for searching for routing information indicating the first address information, wherein the first address information is divided hierarchically by a predetermined number of bits. The first search control information includes first search control information provided in a tree shape corresponding to each layer of the address information, and the first search control information is, for each divided address information of its own layer, the highest order from the divided address information. Whether all of the combined address information obtained by combining up to the divided address information is the highest order of any of the second address information If it matches a part obtained by cutting out part of the divided address information, the information includes information used for referring to lower first search control information, and the entirety of the combined address information or the lowest part of the combined address information. If the truncated one matches all of the second address information, regardless of whether or not the second address information includes information used for referring to the lower first search control information, A computer-readable recording medium on which routing information search control data is recorded, including corresponding routing information or information used for referring to the routing information. 9. The routing information search control data according to claim 8, further comprising routing information search control data including valid information indicating whether each of the routing information is valid or invalid. A computer-readable recording medium that has been recorded. 10. The system according to claim 10, further comprising: the second address information;
It includes second search control information including a network mask corresponding to the second address information and routing information corresponding to the second address information or information used for referring to the routing information. Claim 8
Or a computer-readable recording medium recording the routing information search control data according to 9. 11. The apparatus according to claim 11, wherein the first search control information includes information indicating which part of the first address information each divided address information of its own hierarchy is divided. A computer-readable recording medium recording the routing information search control data described in 8, 9, or 10.