JP3232711B2 - Router relay device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a router relay device in a packet switching communication network between heterogeneous networks.

[0002]

In recent years, in computer network communication, network layer protocols have been extensively and sufficiently developed and verified, and have become widely used with the spread of various computer networks. Accordingly, router devices that connect various computer networks at the network layer level are convenient in terms of management and are economical, so demands are increasing in the field of network equipment.

[0003] Router devices have performance and functional characteristics that need to be improved even now. Among them are relay speed performance and network management functions. In general, the processing of data called a header used for relaying at the network layer is too complicated for a router relay apparatus to be described on a silicon chip, and is often software-processed on a microprocessor. However, the scale of the microprocessor's execution speed is sufficient to relay packet data traffic originating from a network with hundreds or thousands of communication nodes functioning with equivalent performance microprocessors on the network. Not really. This is becoming increasingly important as modern network data transmission speeds increase.

[0004] On the other hand, the router relay device has more management convenience than other lower-level relay devices. In the network layer relay, an address unique to each network protocol is used for relaying between a certain range of networks. In order to relay a different management area, only packet data having an address designating each network area is relayed, and a packet whose destination is unknown or a packet having the same address as that of the network area is discarded. Therefore, compared to a relay device at a lower level of the network layer, the amount of traffic flowing into each network when using many networks is greatly reduced, and abnormal data flows and management problems occur. It greatly contributes to the prevention of leakage of data that has problems. As described above, the router relay device is a network connection device that can connect while controlling data traffic of a large number of networks. However, if too many networks are connected, the data traffic of the network connected to the router is lost. There is a demand to further control and restrict It occurs, for example, in the following cases.

It is assumed that one network is set up for each department in the company and these are connected to one backbone network in the company by a router. Simple in-house communication such as e-mail is performed via a router relay device, while each department uses the database provided for each department on the network within that department and accesses the database from other departments Suppose you want to not let them. At this time, the network layer protocol uses only the address that specifies each department to relay the data packet, so if one department tries to access the database of another department, the packet data is sent to that database. Will flow. Normally, when you want to deny access to a certain system from a certain system, you can use a management means (for example, a password) in the system to block users by restricting users. . However, since data flows to the database device, it is not a sufficient system management measure against various unexpected events caused by abnormal data packets. In addition, there is a possibility of a computer virus or hacking, and there is a case where it is impossible to determine whether or not all the devices have been completely managed by many devices to be managed.

In order to deal with such a situation, a filtering function is used in a recent router relay device. This is a function for relaying or not relaying in the relay system based on the address used in the network layer protocol. As a result, in the above example, it is possible to maintain the integrity of the database by setting the relay system to discard the data packet addressed to each department database.

There is also a demand for adjusting the flow rate of packets relayed by each relay system. When sharing a network with several accounting groups,
In the case where the network is operated in a form provided by one management organization and paid by the other network-subscribing organization, it may be desirable to share the burden according to the state of use. When such charging is performed, various measures may be taken as a measure of the number of usages. In a packet communication network, the number of packets generated in network communication may be used as this measure. This is hereinafter referred to as accounting.

[0008] Functions such as filtering and accounting are already implemented in current router relay devices. In the case of filtering, a process is performed in which a prohibition / permission flag, a source address, and a destination address are set as a set, and if the source address and the destination address of the packet to be relayed match the above set, the packet is not relayed / repeated. In the case of accounting, a set of a source address and a destination address to be accounted is registered, and counting is performed when the source address and the destination address of the packet to be relayed match the pair. However, in consideration of the speed performance proposed at the outset, these processes require a single packet unit for relaying a table search, which is said to require processing time in microprocessor processing. It can be very damaging.

[0009]

2. Description of the Related Art There are many causes for lowering the speed performance. As described in the above-mentioned "Problem to be Solved by the Invention", the microprocessor processing time is one of them.
Therefore, reducing the number of processing steps of the microprocessor is a key to improving the relay speed.

One of the methods adopted to solve this problem is a cache route. This is to omit the search for packet transmission path information (hereinafter, referred to as a routing table) indicating a relay path in the network layer in the relay processing. Here, there is the following rule of thumb regarding the usage status of the relay service of the router relay device.

Rule of thumb a: When a router / communication node performs a process of relaying packet data from a certain source to a certain destination, the next packet data generated is also the source of the previous packet data. Is often sent to the previous destination.

This is essentially because the current computer network communication mainly uses a communication system using a connection-type transport service. When this service is used, the routing table of each router relay device is used. Unless is frequently changed (in fact, dynamic changes in currently widely used routing tables do not change frequently on the order of transit speed). By using one continuous packet relay path.

In the cache route method, this rule of thumb a
The routing table used last time is statically stored on the software using software, and before starting the routing table search process in the next relay, the stored routing table and the destination of the packet to be relayed are used. If the address is matched with the address, that is, if the above-mentioned rule of thumb a is met, the previous routing table is used as it is without entering the search process, thereby ending the routing table allocation process. . This system is still used as a BSD UNIX
Used in machines.

In the cache route method, if the processing speed is prioritized ignoring the protocol stack hierarchy, the number of omitted steps can be further increased. Since the router relay apparatus performs the processing of the protocol below the network layer, the relay processing involves, for example, a processing of adding a data link layer header. The data link header must be assigned the next hop on the packet relay path, that is, the address of the data link layer of the relay destination to which the packet should be relayed or the final destination itself in order to transmit the packet to the final destination. In this processing, in the software procedure, the address of the determined relay destination or final destination is further mapped to the data link layer address when the previous routing table search processing is completed. In other words, a table search also occurs. If the same routing table as the previous one was assigned using the cache route method, the destination of the previous packet and the current destination are the same, so the address of the data link layer is the same as the previous one. Become. For this reason, by holding the previously used data link layer address together in the routing table, the data link layer address mapping process can be omitted.

However, when the addresses of the data link layer are held collectively, a restriction for confirming the validity of the mapping is required. This is because the address of the data link layer used last time may change over time. The data link layer address is often assigned to the device driver of the medium and does not change for the device, but the network layer address is managed by the user to some extent in many protocols. Can be changed freely. This is because the mapping of the system in which the network layer address has been re-installed may not be valid. Thus, this mapping must be refreshed over time.

If the table search technique is refined one more stage, a cache route table may be created. Considering a case where a single processor executes router relay of a plurality of network interfaces, the above-mentioned rule of thumb a may not always be appropriate depending on how the system is constructed. This is because, in this cache route method, the hit rate to the cache route is the key to speeding up. By storing more previous relay information even if it is not the above example, By greatly improving the hit rate, the relay speed could be further improved. On the other hand, however, registration of many cache route entries results in a new table search process of searching the cache route entry table. Therefore, how to determine the number of entries needs to be handled according to the system to be mounted.

As described in the above-mentioned "Problems to be Solved by the Invention", filtering and accounting can be realized on software, but if table search becomes a bottleneck and this relay apparatus is realized, The relay speed is greatly reduced. .

[0018]

SUMMARY OF THE INVENTION The present invention is directed to a router relay device for interconnecting a packet data exchange network at a network layer level, in order to solve the above-mentioned problem of the speed of the router relay device. An address table device capable of registering, deleting, and retrieving the set as one entry, relay history information of a relayed / discarded packet, a set of a source address and a destination address in the network layer of the packet, and the address table device A relay unit that has an address registration unit that holds the address table, searches the address table device, and performs a relay process of a received packet from each network interface using the relay history information registered by the address registration unit. Is a router relay device having

Further, in the present invention, in order to maintain a high speed while executing a filtering process, the router relay device discards the packet requested to be relayed by a set of a source and a destination address of a network layer protocol. A filtering function, wherein the address registration unit also holds filtering history information in the registered entry, and the relay unit performs a filtering function according to filtering history information obtained as a result of a history information search using the address table device. Is a router relay device that realizes the above.

Further, in the present invention, in order to maintain a high speed while executing accounting, the router relay device counts the number of the packets requested by the relay by a set of a source and a destination address of a network layer protocol of the packet. The address registering means also holds accounting history information in the registered entry, and the relay means performs accounting according to the accounting history information obtained as a result of the history information search using the address table device. It is a router relay device that realizes the function.

[0021]

When a filtering function or an accounting function is to be realized at the same time in a system such as the cache route in which the relay history information is retained and used only at the destination address in the network layer, the search procedure of the routing table is omitted. Even if it is possible, in order to execute a filtering function or an accounting function, it is necessary to perform address matching of a combination of a source address and a destination address, so that a table search procedure must be performed as a result. The problem is that by using a set of source address and destination address from the beginning as the search key of the cache route, it is possible to simultaneously execute relay, filtering, accounting, and other protocol extension functions simultaneously by executing the search means once. it can.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a router relay device according to the present invention will be described below.

The construction of this embodiment is described in claims 1, 2, and 3.
It includes embodiments of the described invention. The contents of claims 1, 2, and 3 can be carried out simultaneously, or they can be carried out independently. Regarding independent implementation, (3) in the explanation for each means below
Describe in the relay means.

In this embodiment, some functional blocks are newly incorporated in a relay system incorporated in a conventional router relay apparatus.

In this embodiment, only the processing procedure of the network layer protocol is described. In recent years, communication protocols of computer networks have been hierarchized, and it is possible to implement devices only by describing the processing in the protocol without describing the details of the protocol operation of other layers, In the present invention, the contents that require changes to the conventional router relay device are:
Almost at the network layer level.

FIG. 1 shows the network layer protocol processing procedure (1) of the router relay apparatus of this embodiment, and the processing procedure (2).
2 and 3 and the processing procedure (3) is shown in FIG.
Incidentally, the omitted path and the complete path portion between the broken lines in FIG. 1 are described in FIGS. 2, 3 and 4, respectively.

The newly incorporated processing blocks are (1) an address registration device, (2) an address registration device, (3) an omitted path of a relay device, and (7) an address table device reset device in the following items. The relay means is intended to implement the filtering function and the accounting function in the conventional router relay device, and connects the two processes of searching the address table device and activating the address registration device with the new processing block. The only difference is that the information is stored in the address registration means and the result of the table search processing is held in order to configure the contents to be registered in the address registration means.

The contents of each processing block will be described below. Note that it depends on the protocol input processing procedure and the protocol output processing procedure in FIG. 1, and the operation of each of the implemented protocols in FIGS. 2 and 3 and FIG. The input processing procedure is a protocol processing procedure that cannot be executed unless a routing table search is executed, and the output processing procedure is a protocol processing procedure that can be executed only after a routing table search is executed. The division of the protocol operation procedure is changed as necessary for the operation of the routing procedure. In this embodiment, the content of the division is not described. (1) Address table device The address table device can be realized by describing it with software on a microprocessor that performs a relay process. In this case, the components of the address table device are:
Matching with a required search key (this embodiment requires a device for searching using two network layer protocol addresses as identifiers. Therefore, the entity described as "search key" is these two addresses). , A history information memory for storing history information of entries on the search key table, and an aging timer for aging table entries.

The search key table maps a search request key and history information. The optimal implementation method of the search key table differs depending on the maximum entry number of the table. If the maximum number of entries in the table is small, simple one-by-one entry matching, that is, from the beginning of the software table to the last or first successful search (the search request key exists in the search key table) This is a method for matching each time. This is, for example, when the number of communication nodes connected to the network group to which the router relay device implementing the function of the present invention is connected is not so large,
This is appropriate for the simple extension of the cache route described in the related art, that is, when only the previous relay history information is stored. On the other hand, if the maximum number of entries must be considerably large, a software search speedup method such as a hash search or a binary tree search or a hardware device for table search is used. This means that the claim uses the empirical rule a described in the prior art as a fundamental principle, and in many cases, the search request key does not frequently succeed in the search. Because it can increase the delay of the system, it is necessary to use it in situations where matching is frequently performed, which is a prerequisite for improving efficiency. If the former method, that is, the table is implemented at the entry number level of a few entries, the implementation cost is very small, but the possibility that the search success rate falls if the above example is not applied is large. The latter approach is costly, but will certainly improve efficiency in actual operation. Because of these trade-offs, in this embodiment, the implementation of the search key table is handled as a black box, and it suffices if the search key table satisfies the requirements for matching the search key and the history information table.

The history information memory is where history information such as relay, filtering, and accounting is stored.

The aging timer is a timer for deleting old history information, is started periodically, increments the timer value of all entries in the search key table, and releases the entry when a certain value is exceeded. This is necessary in order to always keep the table entries to a minimum and improve the search efficiency.

The commands that can be requested by the address registration means and the relay means to the address table device are as follows. Key search A key is issued by the user together with the key to be searched, and if there is a match in the search key table, the history information is returned, and a signal indicating that there is no match is returned. -Key deletion If a user issues a key together with a key to be deleted and there is a key to be deleted in the search key table, delete the entry from the table. -Key registration Issued by the user together with the key to be registered and the history information to be registered. If there is a match in the search key table, the history information is updated; otherwise, a new entry is registered. However, if there is no newly vacant entry that can be registered, a new entry is registered after deleting the oldest entry judged from the timer value. (2) Address Registering Unit The address registering unit is configured to execute the currently executed packet relay /
A history flag that encodes the processing content of the discarding process, and some auxiliary information to be stored are configured into one history information,
The key registration command is issued as a key for registering the source address and the destination address of the network layer protocol header of the packet being relayed / discarded, and as the history information for which the history information is to be registered.

As described above, the structure of the history information is constituted by the history flag and the additional information. The history flag can include the following information in one or a plurality of bit flags. • Relay / discard flag Indicates whether the previous packet was relayed or discarded. • Control flag Indicates whether or not there is an operation on the protocol that was processed when the packet was relayed / discarded in the previous relay. -Filtering flag Indicates whether the set of source and destination addresses in this network layer matches an entry on the filtering table. Accounting flag Indicates whether the set of source and destination addresses in this network layer matches an entry in the accounting table.

The attached information corresponds to the presence or absence of the above flag,
Necessary items are configured in the form of tags or fixed structures. -When the relay flag is ON • Output destination network interface number The number for identifying the network interface used for relaying. -Data link information This information is information for executing a transmission procedure in the data link layer which is decisive at the time when the next relay destination at the network layer level is determined, at a high speed. Therefore, how to implement the configuration differs depending on the type of the network interface that outputs the packet to be relayed. If the header of the data link layer is uniquely determined by determining the source and destination addresses of the network layer, the header of the data link layer itself may be left as configuration information, If remains, make up only the decisive part. In any network, what is at least decisive is the destination address and the source address (uniquely determined by the output interface) of the data link layer described in the related art. The manner of construction of this information must be reflected in the procedure of the relay means described later. -When the control flag is on.-Control code As described above, the control flag describes the presence / absence of an operation accompanying the relay / discard on the network protocol. This depends on the type of the network protocol, and cannot be described unconditionally. The following shows the case of the TCP / IP network protocol IP. Note that the registration of an entry with a control flag can be described only if the control processing depends on the source and destination addresses of the network layer being abnormal, etc. For example, if the previous discard operation was discarded due to an error in another area that is not due to the source and destination addresses in the network layer,
This entry is not registered. > ICMP Redirect Processing In a TCP / IP-based ICMP redirect, when a communication node on a network to which it connects outputs a packet, the next relay destination to reach the final destination is determined by the fact that there is a closer next relay destination. Nevertheless, this is a mechanism in which when a relay is erroneously transmitted to a remote relay, the relay transmits an ICMP packet to the destination communication node to select a closer path. In this process, the necessity / unnecessity of the determination is decisive depending on whether or not the source address of the packet to be relayed is on the network to which it is connected. > ICMP unreachable processing ICMP unreachable as an Internet repeater, when its own route information cannot reach the final destination of the packet to be relayed, the ICMP packet is transmitted to the source by the ICMP unreachable. It defines a mechanism that prevents subsequent transmission of packets to the final destination. In this process, the necessity / unnecessity of the process is decisive depending on whether there is a corresponding entry on the routing table. In this case, the relay / discard flag is "discard". -When the filtering flag is on-Filtering entry information When the filtering flag is on, it indicates that the set of source and destination addresses in the network layer corresponds to one of the entries on the filtering table in the filtering process The filtering entry information describes whether the filtering table information is to be relayed or discarded for a set of the source and destination addresses in the network layer of the corresponding relayed packet. -When the accounting flag is on.-Accounting entry information. When the accounting flag is on, the set of source and destination addresses in the network layer indicates that there is an entry in the accounting table in the accounting processing means. The accounting entry information is a pointer to a counter or a temporary counter. (3) Relay Unit The relay unit includes protocol processing of a network layer protocol to be implemented. The relay means is shown in FIGS.
Then, the algorithm of the flowchart as shown in FIG. 4 is obtained.

In the case of a single router relay apparatus, the filtering means and the accounting processing means among the processing means shown in FIG. 4 are not included, and the judgment of the filtering flag and the accounting flag in FIGS. 2 and 3 is performed. Not included. In the case of a single router relay device, the accounting processing means shown in FIG. 4 and the accounting judgment in FIGS. 2 and 3 are not included. In the case of a single router relay device, the filtering processing means shown in FIG. 4 and the filtering judgment in FIGS. 2 and 3 are not included. If the whole is implemented, the claims 1, 2 and 3 will be implemented simultaneously.

First, an input procedure is performed for all relay packets. This input procedure is a procedure for confirming normal reception of a packet at the network layer level, and depends on each network layer protocol to be implemented. The packet determined to be abnormal here is discarded at that time, and has no effect on the subsequent procedure characterized by the present embodiment.

When the input procedure has been completed, the relay processing means issues a key search command using the source and destination addresses of the network protocol header performing the relay process for the address table device as search keys. .
If the search is successful, the procedure moves to the omitted path; otherwise, the procedure moves to the complete path.

In the omitted path, the relay / relay of the normal router is used.
A discarding protocol process is performed, but if the process can be performed with the information registered by the address registration unit, the normal process is not performed. In the omitted path, the history flag is determined, and the corresponding process is performed. The flag may be determined one by one for each flag or may be determined collectively as one flag. -Relay / discard flag If the flag is "discard", take the procedure to discard the packet. If not, the data link protocol processing is performed on the output network interface number of the history information registered by the address registration means based on the information constituted by the data link information. -Control flag When this flag is set, processing according to the control code is executed. In the example of the TCP / IP system described above, if ICMP redirection is described, redirection determination is performed for a packet to be relayed (/ discarded). If it matches the redirect condition specified by the ICMP protocol, it outputs an ICMP redirect packet. On the other hand, if the ICMP unreachable is described, an ICMP unreachable packet is output for the packet to be (relayed /) discarded. -Filtering flag If this flag is set, look at the filtering entry information, and if "relay" is described,
Relay is performed unless the discard flag is “discard”. If “discard” is described, discard is performed regardless of the relay / discard flag. -Accounting flag If this flag is set, the counter is incremented according to the method of configuring accounting entry information.

The complete path activates the address registering means in addition to the normal router relay apparatus protocol processing.
During execution of the normal protocol processing, the history information registered by the address registration means in the address table device is stored in a temporary memory for each packet in the memory. The routing means, the filtering means, and the accounting means are activated in this order. (4) Routing Means The routing means processing may be the routing means of a router relay device that has already been implemented. The processing of the routing means includes a destination address of a packet to be relayed / discarded and a static /
Performs dynamic matching with the destination address of each entry. The routing table has a set of a destination address and a relay destination address, and the relay process performs a process of relaying a packet to the relay destination address. Note that, depending on the network protocol to be implemented, if no matching occurs, control processing described by the control flag of the address registration unit may occur, and this fact is included in the information registered in the address registration unit. . (5) Filtering Unit The filtering unit matches a set of a source address and a destination address of a packet to be relayed / discarded with information in a filtering table. If a match is found, it is included in the information registered in the address registration means. The filtering process for the relayed / discarded packet itself may be performed at that time. However, if the implementation is to continue the processing of the accounting unit even when the packet is discarded, a flag is set and the address registration unit is activated. It is good to start just before. The filtering table is a table in which rules regarding a pair of a source address and a destination address are described in a table format. The rules of this table may be of any type (at least a table of the set of addresses itself is possible), and are not particularly described because they are not within the scope of the present invention. (6) Accounting means The accounting means performs processing very similar to the filtering means. Matching of information in the accounting table is performed on a set of a source address and a destination address of a packet to be relayed / discarded. If there is a match, the counter to be counted is included in the information to be registered in the address registration means. The count of the packet to be relayed / discarded is performed immediately before the relay unit ends. In the accounting table, rules regarding source addresses and destination addresses counted in the same manner as in the filtering table are described in a table format. (7) Address table device reset means This means is not indispensable to the device claimed in the present invention.
The series of address management tables (routing table, filtering table, accounting table) can be changed at any time while the router is operating. In this embodiment, an address table device reset unit is used to satisfy this specification. The address table device is
As described in the address device, the address is reset by the aging timer.If the operation is continued without reflecting the change of the address management table, the relay process is performed according to the old management information until the reset is performed. Will continue. In order to avoid this, in this embodiment, all the registrations registered in the address table device at the time when the address management table is changed are performed by the address table device resetting means using the address table device resetting means. Using the key delete command of As a result, the old registration information is deleted, and the continuous relay processing newly registers the new information through a complete path, so that the relay / discard processing can be immediately performed using the new information.

[0040]

A feature of the present invention is that it has two processing paths for processing packets to be relayed / discarded. Operationally, when a packet is relayed from the source address to the first packet instructed to arrive at the destination address, it first goes through the complete path to each address in the routing table, filtering table, accounting table, etc. The management table is searched for a packet to be relayed / discarded. Each processing block performs the respective processing on the packet (or sets a flag), and at the same time, stores the processing content in a local memory on software, and activates the address registration means to register the content. As a result, in the subsequent relay / discard processing of the packet from the source address to the destination address, the omitted path is set because the pair of the source address and the destination address of the first packet is registered in the address table device. In this case, the relay process is completed without searching the address management tables as performed for the first packet. This omission improves the processing speed performance.

Thus, by implementing the present invention, the process of searching the address management table for relaying / discarding a packet from a certain source address to a certain destination address at the network layer level is the first process for performing the same process. It can be performed only at the time of relaying a packet, without having to search for a later packet.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a network layer protocol processing procedure (1) of a router relay device of the present embodiment.

FIG. 2 is a flowchart showing a part of a network layer protocol processing procedure (2) of the router relay device of the embodiment;

FIG. 3 is a flowchart showing a part of a network layer protocol processing procedure (2) of the router relay device of the embodiment;

FIG. 4 is a flowchart showing a network layer protocol processing procedure (3) of the router relay device of the present embodiment.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-3-270532 (JP, A) JP-A-6-104900 (JP, A) JP-A-64-39852 (JP, A) JP-A-2- 2759 (JP, A) JP-A-4-316244 (JP, A) JP-A-4-144333 (JP, A) JP-A-4-88127 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04L 12/56 H04L 12/46

Claims (3)

(57) [Claims] There a 1. A packet data switching network the router relay apparatus for interconnecting at the network layer level
The source address and destination address to be relayed.
Address, destination address, and relay history information
Search from the address table that stores multiple entries
Search means for performing the search, and the source address and
The set of destination addresses is the entry of the address table entry.
If the source address matches the destination address,
A relay means for relaying process based on the passage history information, source address and addressed to the relay in the searching means
The set of destination addresses is the entry of the address table entry.
If the source address and destination address do not match,
Source and destination addresses that determine the packet transmission path
Using a routing table consisting of multiple combinations
Routing means for performing routing processing; and the relay source address processed by the routing means.
Address and the destination address and the relay history information
Register an entry in the address table and edit the address table.
A router relay device comprising a cable editing means . 2. The address table according to claim 1, wherein
With a configuration in which filtering history information is further added to the configuration
And the relay means includes the relay history information and the filter
Relay processing based on the forwarding history information, and the search means transmits the relay source address and the destination address.
The set of destination addresses is the entry of the address table entry.
If the source address and destination address do not match,
In addition to the routing means, the source and destination addresses
Filtering table consisting of multiple combinations of
Filtering means for performing filtering processing using
Comprising a said address table registering means, the filtering
Processing contents in the means as filtering history information
Add to the address table entry configuration and register
2. The router relay device according to claim 1, wherein the information is recorded . 3. The address table according to claim 1, wherein
Configuration that adds accounting history information to the configuration
, And the said relay unit, the accounting and the relay history information
Relay processing based on the forwarding history information, and the search means transmits the relay source address and the destination address.
The set of destination addresses is the entry of the address table entry.
If the source address and destination address do not match,
In addition to the routing means, the source and destination addresses
Accounting table consisting of multiple combinations of
Accounting that counts the number of packets using
Accounting means for performing an accounting process, wherein the address table registering means comprises:
Processing contents in accounting means as accounting history information
To the configuration of the address table entry
2. The router relay device according to claim 1, wherein the router relay device registers the information.