JP3172099B2 - Relay device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a relay device, and more particularly to a relay device for saving address space used in a network system.

[0002]

2. Description of the Related Art FIG. 15 shows a conventional general WAN.
FIG. 3 is a configuration diagram of (Wide Area Network). FIG. 15 shows three LANs (Local Area
Network) 6, 10, and 11, network systems 1, 7, and 8 are configured respectively, and LANs 6, 10, and 1 are configured.
1 shows a system configuration in which relay devices 104, 109, and 110 are provided for each and connected by dedicated lines 14 and 17. The network system 1 includes a terminal 2 and a WAN
A management device 5 that performs overall management and a relay device 10 that connects to other network systems 7 and 8 and relays between terminals.
4 and a local console 107 connected to the relay device 104. Network system 7
The network system 8 also includes the terminal 3, the relay device 109, and the local console 112, which have functions equivalent to those of the devices included in the network system 1. The network system 8 also includes the terminal 4, the relay device 110, and the local console 113. . LANs 6, 10, and 11 have network addresses NA1, NA2, and NA3, respectively.
However, network addresses NA4 and NA5 are assigned to the dedicated lines 14 and 17, respectively, and form segments.

FIG. 16 is a block diagram showing a conventional relay device. A conventional relay device is a central control unit 21 which is a CPU and executes various kinds of processing in the relay device, and checks the destination, format, etc. of a frame when transmitting data received from one network to another network. A data buffer 22 for temporarily storing the frame, a memory 23 storing programs of various functions processed by the central control unit 21 or data used by the programs, and a local memory connected by RS232C or the like. , 25n connected to the main unit, and a LAN-side control unit 25a,... 25n, which transmits and receives data to and from each of the LAN1,.
, WANn connected to the main unit, and a WAN-side control unit 26 that transmits and receives data from each of WAN1,.
a,... 26n and an internal bus 2 connecting each component
9. In the case of the relay device 104 shown in FIG.
, And two WAN-side control units 26 for connection to the network systems 7 and 8.

[0004] The relay device stores and manages a port status table in the memory 23 for managing a network address allocated to each built-in port. FIG.
7 is a format example of a conventional basic port status table. Also, FIGS. 18, 19, and 20 show the relay devices 104, 109, and 110 based on FIG.
An example of the setting contents of the owned port status table is shown. For example, the relay device 104 has port numbers P1, P
2 and P3, each having a port network address PNA _R1P1 , PNA _R1P2 , PN
A _R1P3 is set.

Further, the relay device manages which port is connected to a configuration of a LAN, a dedicated line, or the like to which the network addresses NA1 to NA5 are allocated, and specifies a route for performing data transfer. A route information table for setting route information for the server is stored in the memory 23 and managed. FIG. 21 shows a format example of a conventional basic route information table. In the “destination network address information”, a network address assigned in the WAN is set. The “relay destination relay device address information” includes, in the relay device, the data to be transmitted to the network address to which port of which relay device should be sent, that is, the port network address of the relay device to be relayed Set. When a configuration such as a LAN to which a network address is assigned is directly connected to a port of the relay device, the network address of the port of the relay device is set. "Measure" indicates the number of relay devices that pass through to deliver data to its network address. Since the data to be relayed always passes through the own relay device, at least 1 is usually set for the measurement. The “output port number” sets the port number of the relay device that sends out the data in order to send the data to the network address.
FIGS. 22, 23, and 24 show the setting contents of the route information tables owned by the relay devices 104, 109, and 110 based on FIG. 15, respectively. For example, the relay device 10
4, the LAN 6 whose network address is “NA1” is directly connected to the port P2 of the own relay device R1.
The "P2 address of 1" is set to "1" for "Measurement", and "P2" is set for "output port number". The LAN 10 having the network address “NA2” is directly connected to the port P2 of the relay device R2. However, the relay device R1 transmits the data to the LAN 10 from the port P1 of the relay device R1. Since it is necessary to send data to the port P1 of the destination, "address of R2 P1" is set in "relay destination relay device address information", and "P1" is set in "output port number".
Further, since the data passes through the relay devices R1 and R2 until the data arrives at the LAN 10, "Measurement" becomes "2". Similarly, various information is set for the remaining network addresses NA3 to NA5, and the path information is set for the other relay devices R2 and R3 in the same manner. The dynamic path control for dynamically setting the path information will be described later.

[0006] When a network constructed by the TCP / IP protocol is connected to the Internet, a host on the Internet is required to provide a uniquely determined I / O.
A P address is allocated. This IP address is uniquely assigned all over the world, and the user can use an IP address whose registration has been permitted by application. However, an address determined by the user can be freely assigned to each host in the network system that is not directly connected to the Internet. However, a unique net ID corresponding to the assigned IP address and a unique address in the network system are assigned. 3 consisting of host ID
A 2-bit address is assigned. This address corresponds to the network address described above. By assigning a network address based on the IP address to each component in the system, IP addresses are saved on a world level.

Next, a method of assigning a network address and a method of creating a port status table will be described. FIG. 25 shows two relay devices for connecting three LANs. Each of the LAN-1, LAN-2, and LAN-
3 is a class A network address "10.1.0.
0 "," 10.2.0.0 ", and" 10.3.0.0 ", respectively.
The port on the AN-1 side has a net ID “10” and a LAN
"1" including the subnet part "1" assigned to -1
A network address of 0.1.0.1 is assigned to the LAN-2 port of the relay device A. The port includes a net ID "10" and a subnet portion "2" assigned to LAN-2. Similarly, a network address “10.2.0.0.1” is assigned to the port on the LAN-2 side of the relay device B. The network address overlaps with “10.2.0.1” already assigned in the relay device A. The network address “10.2.0.2” is assigned, and the port on the LAN-3 side is assigned a net ID.
The network address “10.3.0.0.1” including “10” and the subnet portion “3” allocated to the LAN-3 is allocated. As described above, each network address assigned to a port can be set by assigning a network address to a segment such as a LAN or a dedicated line connected to the relay device. When the network address of each port is uniquely determined, it is registered as a port network address in the port status table.

[0008] Here, in FIG.
The operation of the conventional relay device will be described by taking data transmission as an example. However, in the above conventional example shown in FIG. 15, the IP address allocated to the WAN is, for example, “123.234.0.0” of class B,
For example, if the network address NA2 of the LAN 10 is "1"
23.234.100.0, the terminal 3 has the net ID “123.234” and the subnet portion “100”.
"123.234.100.n" (n
= 1 to 254).

[0009] When the relay device 104 receives data from the terminal 2 connected to the LAN 6, the address information of the destination includes "123.234.100". The data is transmitted from the port P1 to the port P1 of the relay device 109. When receiving the data from the port P1, the relay device 109 stores "123.234.
100 "is included, the data is transmitted from the port P2 of the relay device 109 with reference to the path information table. In this way, the terminal 3 receives the transmitted data via the LAN 10. In other words, the relay device 104 transmits “123.234.100”, which is a combination of the net ID and the subnet portion, to the terminal 2
Terminal 3 by obtaining from the address information of the terminal 3 transmitted from the terminal 3 and by referring to the route information.
The connection is found to be connected to the AN 10 and the data is transmitted to the relay device 109 to which the LAN 10 is connected.

Next, dynamic path control will be described. For example, the TCP / IP protocol uses RIP (Routing Information) to perform dynamic routing.
By adopting a routing protocol called “nProtocol”, the above-described route information (RIP information) can be sequentially exchanged between each of the relay devices in order to identify a route.
It is possible to know from which port of which relay device the information was transmitted and which port of its own relay device received it. That is, each relay device can sequentially update the contents of the route information table with the route information sent from another relay device by operating the RIP.
The routing information table corresponds to a routing table in TCP / IP.

The relay device transmits data received from the transmission source from the port to which the transmission destination is directly or indirectly connected, based on the route information set by the RIP. In order to operate the RIP for dynamically setting path information used for routing, a network address must be assigned to each port. In order to assign a network address to each port, the network address must be assigned to a configuration such as a LAN or a dedicated line that is directly connected as described above. In the example shown in FIG.
The network address of each port of each of the ports 04, 109, and 110 has a connected configuration, that is, LANs 6, 10, and
It can be set by assigning a network address to each of the dedicated lines 11 and the dedicated lines 14 and 17.

[0012]

As described above, the IP address that is the source of the network address to be assigned is unique worldwide and is not assigned without registration permission. Finite.
For example, for a class C IP address, a maximum of 255,
If it is a class B IP address, only a maximum of 255 ² network addresses can be assigned.

However, in the conventional relay device, R
In order for the IP to operate, a network address must be allocated to each port, and therefore a network address must be allocated to a LAN or the like. The necessity of allocating a network address to a port, a LAN, or the like that does not become an actual transmission / reception destination of data results in wasteful use of the IP address space, which hinders construction of a large-scale network system. Becomes Of course, it is possible to receive a plurality of IP addresses, but currently there is a shortage of IP addresses worldwide. Therefore, it is desired to efficiently manage and manage network addresses in the assigned IP address space.

[0014] Of course, route information can be statically set without using RIP, but operation management is enormous, which is not practical in a large-scale network system. If the RIP is not used, the path cannot be automatically switched and the reliability is impaired. Therefore, there is a demand for operating the RIP after all. That is, conventionally, in order to perform dynamic route control by RIP or the like, it is necessary to set a network address for each of the connected LAN and dedicated line while knowing that it is useless.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a relay device capable of dynamically setting path information while saving address space. is there.

[0016]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a network system which sets a network address for each port and relays data between terminals communicating via a network. In the relay device, the relay device has a port status table for registering a network address properly set to at least one port and a network address already set properly to another port as a substitute network address. It is characterized in that the same network address is assigned to the same. In other words, dynamic route control can be performed even when the same network address is assigned, so that address space can be saved without being wasted.

Further, the relay device has route information request means for dynamically making a route information transmission request by transmitting a route information request frame, wherein the route information request means has a substitute network address set therein. When transmitting a route information request frame from a port, the substitute network address set for the port is set as the source address of the route information request frame.

Further, the relay device has a route information request receiving means for receiving a route information request frame, and the route information request receiving means transmits a route information request frame received from a port to which a substitute network address is set. The present invention is characterized in that even when a network address belonging to a non-adjacent network is set in the included source address, the route information request frame is accepted without being fraudulent.

The relay device may further include a route information table storing route information including destination network address information and relay destination relay device address information, a response to the received route information transmission request, and a route information response frame. Routing information transmission means for dynamically performing transmission by transmitting, when transmitting a routing information response frame from a port to which a substitute network address is set, the source address of the routing information response frame The substitute network address set to the port is set, and the path information stored in the path information table is set in the information field of the path information response frame.

The relay device includes a route information table storing route information including destination network address information and relay destination relay device address information; a route information receiving unit for receiving a route information response frame; Routing information updating means for updating the routing information table based on the information, wherein the routing information receiving means is located adjacent to the source address contained in the routing information response frame received from the port set with the substitute network address. It is characterized in that even when a network address belonging to a non-performing network is set, it is accepted without being fraudulent.

That is, according to the present invention, even if a substitute network address is set in the source address of each frame used for the route information, the frame in which the substitute network address is set is accepted without being fraudulent. Therefore, dynamic path control can be performed normally.

The port status table includes, for each port for which a substitute network address is set, a port number to which a substitute network address is assigned, a substitute flag indicating that the substitute network address has been set, and , Is stored.

Further, the relay device has port status table management means for managing the port status table,
The port state table management means may not delete a network address used as a substitute network address.

Further, the relay device is characterized in that it has port status display means for displaying the contents of the port status table.

Further, the relay device has means for transmitting the contents of the port status table to a management device in a network system. Thereby, the contents of the port status table individually held by each relay device in the network system can be displayed on the management device collectively.

[0026]

Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a WAN including an embodiment of a relay device according to the present invention. Basically, it is the same as FIG. 15 shown in the conventional example, and similar elements are denoted by the same reference numerals. However, in the present embodiment, it is not necessary to assign a network address to the dedicated lines 14 and 17.

FIG. 2 is a block diagram of the relay apparatus according to the present embodiment. Although the configuration is basically the same as the conventional configuration shown in FIG. 16, the contents of the port status table and the path information table stored in the memory 23 are different from those of the conventional configuration.
Further, the central control unit 210 according to the present embodiment includes a route information request unit that dynamically sends a route information request by transmitting a route information request frame, a route information request receiving unit that receives a route information request frame, A route information transmitting unit that dynamically responds to the received route information transmission request by transmitting a route information response frame, a route information receiving unit that receives the route information response frame, and a route information table based on the received route information. It is a route information updating means for updating, and operates dynamic route control. Further, the central control unit 210 is a port status table management unit that manages the port status table.

FIG. 3 is a diagram showing an example of the format of the port status table of the relay device according to the present embodiment. FIGS. 4, 5, and 6 show examples of setting contents of the port status tables owned by the relay devices 104, 109, and 110 based on FIG. 1, respectively. As shown in FIG. 2, the port status table includes, for each port, a “substitute network address” which is a feature of the present embodiment,
Fields of “substitution source port number” and “substitution flag” are separately provided.

In the present embodiment, dynamic routing control, that is, TC
Although the purpose of the P / IP is to operate the RIP, in the present embodiment, each relay device 10
A network address is set to only one of the ports of 4,109,110, and the set network address is substituted for the other ports, so that the network address is not set uselessly. And

Therefore, when a network address is properly set in the “port network address” of the port status table by the same method as in the related art, the network address is set. It should be noted that the network address set here will be referred to as a regular network address as necessary to clearly distinguish it from a substitute network address described below. In the “substitute network address”, when substituting a legally set network address, a substitute regular network address is set. Therefore, the address is set to either the “port network address” or the “substitute network address” depending on whether the network address is properly set or substituted. In the case of substituting a network address for the “substitution source port number”, a port number serving as a substitution source in which a regular network address is set, and in the “substitution flag”, whether to substitute a network address is set. In the case of the present embodiment, “RESET” is set when a network address is properly set and not substituted, and “SET” is set when substituted.
Are set respectively. When the network address is properly set to only one port of each of the relay devices 104, 109, and 110 as in the present embodiment, it is possible to normally operate the dynamic path control only with the “substitute flag”. However, when network addresses are properly set for a plurality of ports of each of the relay devices 104, 109, and 110, it is necessary to specify a substitute source for each port. address"
Alternatively, a “substitute source port number” is required. This port status table is created and updated by a network administrator or the like when the WAN is constructed or when the configuration is changed, but can be automatically created by an application or the like.

According to the present embodiment, the network address need only be set to at least one of the ports of the relay devices 104, 109, and 110 as described above.
It is not necessary to assign a network address not only to a port that substitutes a network address but also to a dedicated line connected to the port, so that address space can be saved and dynamic route control that dynamically sets route information can be performed. Can work.

The port status table will be described in detail using a specific example. The relay device 104, as shown in FIG. 1, has the LA to which the network address “NA1” is assigned.
N6 is connected to port P2, and dedicated lines 14, 17 to which no network address is assigned are connected to ports P1, P3, respectively. That is, the network address to which the relay device 104 connects is assigned only to the LAN 6 connected by the port P2. Therefore, like the setting contents of the port status table shown in FIG. 4, first, "PNA _R10P2 " is set to the "port network address" of the port P2. Also, “RESET” is set in the “substitute flag”.

On the other hand, the ports P1 and P3 substitute network addresses, but the relay device 104
Since only the regular network address is assigned to the port P2, it is uniquely determined to substitute the network address of the port P2 as the port network address. Therefore, "PNA _R10P2 " is _assigned to the "substitute port network address" of each port P1, P3.
“P2” is set to “substitute source port number”, and “SET” is set to “substitute flag”. Note that "NULL" is set in fields other than those described above. The port status tables in the relay devices 109 and 110 are also set as described above.

FIG. 7 is a diagram showing an example of the format of the route information table in the present embodiment. The format itself is the same as the conventional example, but the setting method for the “relay destination relay device address information” is different. This will be specifically described using the route information table of the relay device R10 shown in FIG.

In the "relay destination relay device address information", a port network address of a relay device to be a relay destination is set. Therefore, the “port network address” of the network address “NA1” includes
The port network address of the port P2 of the relay device R10 is set as in the conventional example. On the other hand, the “port network address” of the network address “NA2”
Is the port P of the relay device R20 which is the relay destination.
1 should be set, but its port P
As is clear from the port status table of the relay device R20 shown in FIG. 5, No. 1 does not set a regular network address and substitutes the network address of the port P2. Therefore, the “port network address” of the network address “NA2” in the relay device R10 is set to the port network address of the port P2 that is a substitute for the port P1 of the relay device R20. The port address of the network device “NA3” should be set to the address of the port P1 of the relay device R30 that is the connection destination, but the port P1 is the relay port shown in FIG. Device R
As is clear from the port status table of No. 30, the regular network address is not set, and the network address of port P2 is substituted. Accordingly, the “port network address” of the network address “NA3” in the relay device R10 is set to the port network address of the port P2 that is a substitute for the port P1 of the relay device R30.

As described above, each piece of route information is registered in the route information table of the relay device R10, and the other relay devices R20 and R30 are similarly registered. 9 and 1
0 shows an example of the setting contents of each of the relay devices R20 and R30. Each relay device can dynamically obtain the contents of the route information table of another relay device by operating the dynamic route control, and create and update the route information table by obtaining the contents. However, a method of acquiring the route information will be described later.

A feature of the present embodiment is that the network address set for a certain port is substituted for another port, so that the dynamic route control is operated without setting the network address uselessly. Is to be able to do things. Next, transmission / reception processing of a path information request frame and transmission / reception processing of a path information request frame of dynamic path control according to the present embodiment will be described. In the present embodiment, T
Before describing the case where RIP in the CP / IP protocol is adopted, a route information frame (RIP frame) used when transmitting and receiving route information in RIP will be described with reference to FIG. The schematic configuration of this path information frame is the same as the RIP request frame used when making a request for transmission of path information and the RIP response frame used when returning a transmission request, and specifies the relay device that is the transmission destination of the frame. A "destination network address", a "source network address" that identifies the relay device that is the source of the frame,
Set "information field". However, since a network address is not assigned to the relay device itself,
In the “destination network address”, the port network address of the relay device that is the relay destination of the RIP frame,
In the “source network address”, a port network address for transmitting a RIP frame is specified. In the “information field”, route information at the time of RIP reply is set.

First, a process for making a request to transmit a RIP frame to acquire route information from another relay device will be described with reference to an example in which a RIP request frame is transmitted from the relay device R10 to the relay device R20.

The relay device R10 stores the port P of the relay device R20 in the “destination network address” of the RIP frame.
Set 1. Also, the normal network address of the port P1 of the relay device R10 that sends out the RIP frame is normally set as the “source network address”. However, in the present embodiment, the regular network address shown in the port status table of FIG. As described above, since the regular network address is not set for the port P1 and the network address is substituted, the network address of the port P2 serving as the substitute source is set. The relay device R10 sends the RIP request frame set in this way to the relay device R20.

Next, the reception process of the RIP request frame will be described with reference to the flowchart shown in FIG.
The following describes an example in which the relay device R20 receives a RIP request frame from the relay device R10.

Normally, according to the rule of the protocol called RIP, when a relay device receives a RIP request frame, it is valid only when the network address of the source of the RIP request frame is included in a network adjacent to the relay device. Is supposed to. Whether it is adjacent is determined by the net ID of the network address of the port that received the RIP request frame
Of the source address included in the RIP request frame and the combined value of
It can be determined by comparing D with the combined value of the subnet portion. In RIP,
It can be easily determined using a network mask (not shown) set in the port status table.

However, in the present embodiment, when a RIP request frame is received, first, the state of the substitute flag of the received port in the port state table is referred to (step 101). When the substitute flag is “SET”,
In other words, if the received port substitutes for the network address, the process proceeds to the RIP response frame transmission process without performing the check in step 102 (step 103). If the substitute flag is “RESET”, that is, if a regular network address is assigned, it is determined whether or not the substitute flag is included in the network adjacent to the relay device R10 as in the case of the related art (step 102). Only when the request has been received, the RIP request frame is accepted, and the process proceeds to the transmission processing of the RIP response frame (step 103). If the received RIP request frame is not included in the network adjacent to the relay device R20, the received RIP request frame is discarded (step 10).
4).

According to the port status table of the relay device R20 shown in FIG. 5, since the port P1 that has received the RIP request frame from the relay device R10 uses the substitute network address, the process of step 102 is not performed. Even if a network address of a non-adjacent network such as the port P2 of the relay device R10 is set in the “transmission source network address” of the RIP request frame, it is accepted without judging that it is invalid.

Next, the transmission processing of the RIP response frame in step 103 will be described with reference to an example in which a RIP response frame is transmitted from the relay device R20 to the relay device R10.

The relay device R20 stores the port P of the relay device R10 in the “destination network address” of the RIP frame.
Set 1. Also, the regular network address of the port P1 of the relay device R20 that sends out the RIP frame is normally set as the “source network address”, but in the present embodiment, it is shown in the port status table of FIG. As described above, since the regular network address is not set for the port P1 and the network address is substituted, the network address of the port P2 serving as the substitution source is set. Then, the contents of the path information table shown in FIG. 9 are set in the “information field” as the path information. The relay device R20 sends the RIP response frame set as described above to the relay device R10.

Next, the reception processing of the RIP response frame will be described based on the flowchart shown in FIG.
The following describes an example in which the relay device R10 receives a RIP response frame from the relay device R20.

Normally, according to the rule of the protocol called RIP, when the relay device receives the RIP response frame, the network address of the source of the RIP response frame is included in the network adjacent to the relay device, as in the case of the RIP request frame. Valid only if The method of judging whether or not they are adjacent is the same as in the case of the RIP request frame.

However, in the present embodiment, when a RIP response frame is received, first, the status of the received port substitution flag in the port status table is referred to (step 111). When the substitute flag is “SET”,
In other words, if the received port substitutes for the network address, the process proceeds to the registration processing in the route information table without performing the check in step 112 (step 11).
3). If the substitute flag is “RESET”, that is, if a regular network address is assigned, it is determined whether or not the substitute flag is included in the network adjacent to the relay device R10 as in the case of the related art (step 11).
2) Only when the RIP response frame is included, the RIP response frame is accepted, and the process proceeds to the registration processing to the routing information table (step 113). If the received RIP response frame is not included in the network adjacent to the relay device R10, the received RIP response frame is discarded (step 114). In the process of registering in the path information table, the relay device R10 is connected to the LAN directly connected to the relay device R20 that is the transmission source.
The route information relating to the ten network addresses “NA2” is registered in the route information table. At this time, the weighing value is updated as necessary.

According to the port status table of the relay device R10 shown in FIG. 4, since the port P1 which has received the RIP request frame uses the substitute network address, the process of step 112 is not performed.
Even if a network address of a non-adjacent network such as the port P2 of the relay device R20 is set in the “source network address” of the P request frame, the request is accepted without judging that it is invalid.

Similar to the route information acquisition process performed by the relay device R10 for the relay device R20, the relay device R20 may perform the process on the relay device R10, and the relay device R10 may perform the process on the relay device R30. it can. Further, the routing information can be similarly exchanged between the relay device R20 and the relay device R30 that are not directly connected.

As is clear from the above description, in order to set the substitute network address, the regular network address must be set to at least one port. Further, when the assigned regular network address is deleted, if the regular network address is used as a substitute network address, inconvenience occurs. Therefore, it is necessary to manage the port status table. In the present embodiment, the central control unit 210
Manages the network address, and deletes the network address assigned to the port.
This will be described with reference to the flowchart shown in FIG.

First, when a port to be deleted is designated, the substitute flag of the port is referred to (step 1).
21). If the substitute flag is not “RESET”,
"SET", that is, the port set to that port is a substitute network address, so that it is not substituted from another port. Therefore, the settings can be updated without depending on other ports. When assigning a regular network address from the substitute, the regular port network address is assigned to a predetermined field of the port status table, the substitute original port number is deleted, and the substitute flag is changed to "RESET" (step 122).

If the substitute flag is "RESET", that is, if a regular network address is set for the port, it is checked whether another port substitutes the port. This can be known by checking whether or not the port number is set in the substitute source port number in the port status table (step 12).
3). If there is a port for which the port number is set, it means that the port substitutes the network address of the port, and it cannot be forcibly deleted. An error is displayed on the local console as not possible (step 124). If the port number is not set in the substitute port number, it can be determined that the network address of the port is not substituted by another port, and the network address of the port can be deleted ( Step 125). In this way, it is possible to prevent the adverse effects of substituting the network address.

As described above, according to the present embodiment, as long as at least one regular network address is set in each of the relay devices 104, 109, and 110, the regular network address can be substituted for other ports. And RI
P can operate. In addition, the fact that the route information can be exchanged as described above means that data communication between terminals can be performed by using a substitute network address.

In the above example, a case has been described in which the network addresses are not assigned to the dedicated lines 14 and 17, but in the present embodiment, the relay devices 104, 109 and 110
Since it is only necessary to set at least one regular network address in the network, the network addresses can be assigned to the dedicated lines 14 and 17, and the substitute network addresses can be assigned to the LANs 6, 10, and 11. Also, the present invention can be realized by a configuration in which a plurality of LANs are connected to the relay device, and the same effects as described above can be obtained.

The configuration of the conventional WAN shown in FIG. 15 is the same as the configuration of the WAN of this embodiment shown in FIG. 1, except for the terminal, the management device, and the local console which have the same configuration. Conventionally, the number of network addresses normally allocated is 7, a relay device, 3 for a LAN, and 2 for a dedicated line. In this embodiment, a total of 12 network addresses is used. 0, for a total of six. Assuming that network addresses are allocated to dedicated lines, there are a total of five relay devices, three LANs, and two dedicated lines. Even in the simple network configuration shown as such an example, the address space used can be halved. Therefore, it can be said that the greater the network configuration and the greater the number of ports of the relay device, the greater the effect of the present embodiment.

By the way, the port status table used in the above dynamic accounting control includes
09 and 110 respectively. Therefore, the port status table display means is changed to each of the relay devices 104, 109,
110, the contents of the port status table are displayed. In the present embodiment, the local consoles 107, 112, and 113 are used as port status table display means. Thereby, each of the relay devices 104, 109, 1
The setting contents of the network addresses that are individually held by the network 10 can be displayed.

In the present embodiment, the management device 5
The contents of the port status table held by each of the relay devices 104, 109, and 110 in the AN can be displayed collectively. This is because each of the relay devices 104 and 10
9 and 110, a means for transmitting the contents of the port status table to the management device 5 can be realized. In the present embodiment, the contents of the port status table retrieved from the memory 23 by the central control unit 210 are stored in the LAN. It is sent from the side control unit 25 or the WAN side control unit 26. Upon receiving the contents of the port status table from each of the relay devices 104, 109, and 110, the management device 5 displays the contents of the port status table collectively. Of course, the management device 5 can perform not only the display but also the management of the history, the number of valid ports, and the number of regular network addresses set to the ports, based on the contents of the port status table.

In the present embodiment, the case where RIP in the TCP / IP protocol is mainly used as the dynamic path control has been described as an example, but the present invention is not limited to this.

[0061]

According to the present invention, as long as a network address is properly set in at least one port of the relay device, the other ports use the properly set network address in place of the dynamic route. The control can be operated. Therefore, it is not necessary to set a network address to a port using the substitute network address, and it is not necessary to assign a network address to a dedicated line or the like connected to the port. Therefore, it is possible to greatly save the address space.

In particular, in the present invention, information relating to a port for which a network address is properly set and a port for substituting a properly set network address are registered in a port status table. Since the substitute flag is set, the network address can be easily managed.

Further, since the port status table management means for managing the port status table is provided, it is possible to prevent inconvenience in the operation management of the network address such as not to delete the substitute network address. .

Further, a route information requesting means, a route information request receiving means for enabling use of a substitute network address,
Since the route information transmitting means and the route information receiving means are provided,
Even if a network address that is not included in the network adjacent to the source address of the path information frame used for dynamic path control is set, it is possible to perform processing related to dynamic path control without judging that it is invalid. Become.

Further, since the port status table display means is provided for each of the relay devices, the setting contents of the network address held individually by each of the relay devices can be displayed.

Further, since a means for transmitting the contents of the port status table to the management device is provided in each relay device, it is possible to collectively display the contents of the port status table on the management device.

[Brief description of the drawings]

FIG. 1 is a block diagram of a WAN including an embodiment of a relay device according to the present invention.

FIG. 2 is a block diagram of a relay device according to the present embodiment.

FIG. 3 is a diagram illustrating a format example of a port status table of the relay device according to the present embodiment.

FIG. 4 is a diagram showing an example of setting contents of a port status table of the relay device R10 according to the present embodiment.

FIG. 5 is a diagram showing an example of setting contents of a port status table held by the relay device R20 according to the present embodiment.

FIG. 6 is a diagram illustrating an example of setting contents of a port status table of the relay device R30 according to the present embodiment.

FIG. 7 is a diagram showing a format example of a route information table according to the embodiment.

FIG. 8 is a diagram showing an example of setting contents of a route information table held by the relay device R10 according to the present embodiment.

FIG. 9 is a diagram showing an example of setting contents of a route information table held by the relay device R20 according to the present embodiment.

FIG. 10 is a diagram showing an example of setting contents of a route information table held by the relay device R30 according to the present embodiment.

FIG. 11 is a schematic configuration diagram of a path information frame according to the present embodiment.

FIG. 12 is a flowchart showing a reception process of a route information request frame in the present embodiment.

FIG. 13 is a flowchart showing a reception process of a path information response frame in the present embodiment.

FIG. 14 is a flowchart showing a process of deleting a port network address in the present embodiment.

FIG. 15 is a block diagram of a WAN including a conventional relay device.

FIG. 16 is a block diagram of a conventional relay device.

FIG. 17 is a diagram showing a format example of a port status table of a conventional relay device.

FIG. 18 is a diagram showing an example of setting contents of a port status table of a conventional relay device R1.

FIG. 19 is a diagram showing an example of setting contents of a port status table of a conventional relay device R2.

FIG. 20 is a diagram showing an example of setting contents of a port status table of a conventional relay device R3.

FIG. 21 is a diagram showing a format example of a conventional route information table.

FIG. 22 is a diagram showing an example of setting contents of a route information table possessed by a conventional relay device R1.

FIG. 23 is a diagram showing an example of setting contents of a route information table of a conventional relay device R2.

FIG. 24 is a diagram showing an example of setting contents of a route information table held by a conventional relay device R3.

FIG. 25 is a network configuration diagram shown to explain a conventional network address allocation method.

[Explanation of symbols]

1, 7, 8 network system, 2, 3, 4 terminal, 5 management device, 6, 10, 11 LAN, 23 memory, 24 local console control unit, 25 LAN side control unit, 26 WAN side control unit, 29 internal bus, 10
4, 109, 110 relay device, 107, 112, 11
3 Local console, 210 Central control unit.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04L 12/56 H04L 12/28 H04L 12/46 H04L 12/66

Claims (9)

(57) [Claims] 1. A relay device in a network system for setting a network address to each port and relaying data between terminals communicating via a network, wherein the relay device has a network that is properly set to at least one port. A relay device, comprising: a port status table for registering an address and a network address that has already been properly set to another port as a substitute network address, and assigning the same network address to a plurality of ports. 2. The relay device includes a route information request unit that dynamically transmits a route information request by transmitting a route information request frame, wherein the route information request unit has a substitute network address set therein. 2. The relay device according to claim 1, wherein when transmitting the path information request frame from the port, the substitute network address set for the port is set as the source address of the path information request frame. 3. The relay device includes a route information request receiving unit that receives a route information request frame, wherein the route information request receiving unit transmits a route information request frame received from a port to which a substitute network address is set. 2. The relay device according to claim 1, wherein even when a network address belonging to a non-adjacent network is set in the included source address, the relay device accepts the route information request frame without making it illegal. 4. A routing information table for storing routing information including destination network address information and relay destination relay device address information, a response to a received routing information transmission request, and a routing information response frame. A routing information transmitting unit that dynamically performs transmission by transmitting the routing information response frame, wherein the routing information transmitting unit transmits a routing information response frame from a port in which a substitute network address is set. 2. The relay device according to claim 1, wherein the substitute network address set to the port is set to the address, and the route information stored in the route information table is set to the information field of the route information response frame. 5. A route information table for storing route information including destination network address information and relay destination relay device address information; a route information receiving unit for receiving a route information response frame; Routing information updating means for updating the routing information table based on information, wherein the routing information receiving means includes a source address included in a routing information response frame received from a port set with a substitute network address, 2. The relay device according to claim 1, wherein even when a network address belonging to a network that is not adjacent to the network is set, it is accepted without being illegal. 6. The port status table includes, for each port for which a substitute network address is set, a port number to which a substitute network address is assigned, a substitute flag indicating that the substitute network address has been set, and The relay device according to claim 1, wherein 7. The relay device has a port status table management unit that manages the port status table, and the port status table management unit disables deletion of a network address used as a substitute network address. 7. The relay device according to claim 6, wherein: 8. The relay device according to claim 1, wherein the relay device has port status display means for displaying the contents of the port status table. 9. The relay device according to claim 1, wherein the relay device has means for transmitting the contents of the port status table to a management device in a network system.