JP3389871B2 - Packet communication network, packet communication network construction method, and node device of packet communication network - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packet communication network for transferring a packet to a node device or terminal designated by a destination address, a packet communication network construction method, and a node device of the packet communication network. More specifically, the present invention relates to a packet communication network using a pseudo sub-network having the same pseudo sub-network address, a packet communication network construction method, and a node device of the packet communication network.

[0002]

2. Description of the Related Art Conventionally, there have been two methods for constructing this type of packet communication network.

In the first method, the addresses of the node devices forming the packet communication network are hierarchized based on the installation location of the node devices, and the hierarchized addresses are used to make the node device the packet is intended for. It is a method of routing according to the route to reach.

In the second method, the node device receiving the packet fetches only the packet addressed to the own node device and directs all the packets other than those addressed to the own node device to all the node devices connected to the own node device. It is a method of transferring. As an example of the first method, "Internetworking TCIP IP Volume 1, Principles Protocols and Architecture" (Internetworking Wi
th TCP / IP Vol. 1, Principle
s, Protocols, and Archite
Cture) (Prentice-Hall, 19)
1995) is a packet communication network (hereinafter referred to as an IP network). In addition, as an example of the second method,
There is a packet communication network described in Japanese Patent Laid-Open No. 9-162925.

FIG. 4 is a block diagram showing a method of constructing a packet communication network by the IP network, which is the first method. In FIG. 4, the node device 110 and the node device 120 are connected by the transmission line 151 to the IP sub-network A.
, And the node device 120 and the node device 130 are connected by the transmission path 152 using the IP sub-network B.

The node device 110 includes a port W111, a port E112, a port S113, and a routing unit 1.
14, the node device 120 includes the port W121, the port E122, the port S123, and the routing unit 1.
24, the node device 130 includes a port W131, a port E132, a port S133, and a routing unit 1.
34, the node device 140 includes a port W141, a port E142, a port S143, and a routing unit 1.
44 are provided. Each port has an IP address described in the frame. The capital letters at the beginning of the IP address represent the IP subnetwork address, and the numbers after that represent the IP host address. Also, the routing unit 1
41, 142, 143, 144 respectively have routing tables 115, 125, 135, 145 inside,
Based on the information in this routing table, the received IP packet is routed to each port. The routing table is, for example, IETF (Intern).
et Engineering Task Forc
e) RFC (Request for Commen)
ts) 1058, 1723 RIP (Rou
toning Information Protocol
It can be constructed using means such as l). By using the RIP, each node device can detect deletion and addition of the node device, and the routing table can be automatically constructed without setting by the administrator.

Next, the procedure for adding the node device 140 to the IP network composed of the node devices 110, 120 and 130 will be described with reference to FIGS.

First, a procedure for adding the node device 140 between the node device 110 and the node device 120 shown in FIG. 4 will be described with reference to FIG. In this case, the connection between the node device 110 and the node device 120 is cut off, and the node device 110 and the node device 140 are connected by the transmission line 151. Further, a new IP sub-network C is constructed between the node device 140 and the node device 120 by the transmission line 153. Along with this, port W141 and port E
The IP address of 142 is set to A2 and C1, respectively. Further, the IP address of the port W121 of the node device 120 is changed to C2. Routing table 11
5,125,135,145 are automatically updated by RIP.

Next, a procedure for adding the node device 140 between the node device 120 and the node device 130 shown in FIG. 4 will be described with reference to FIG. In this case, the connection between the node device 120 and the node device 130 is cut off, and the node device 120 and the node device 140 are connected by the transmission line 152. Further, a new IP sub-network C is constructed between the node device 140 and the node device 130 by the transmission line 153. Along with this, port W141 and port E
The IP address of 142 is set to B2 and C1, respectively. Further, the IP address of the port W131 of the node device 130 is changed to C2. Routing table 11
5,125,135,145 are automatically updated by RIP.

As described above, I according to the first method
In the P network, when the node device 140 is added between the node device 110 and the node device 120,
When adding between the node device 120 and the node device 130, it is necessary to set different IP addresses to each node.

Taking the case of FIG. 6 in which the node device 140 is added between the node device 120 and the node device 130 as an example,
The packet routing operation will be described. In FIG. 6, the routing units 114, 124, 134, 14
4 is the updated routing table 115, 12
The IP packet is routed to each port based on the information of 5,135,145. For example, when an IP packet whose destination IP address is C1 is received by the port S113 of the node device 110, the routing unit 114 refers to the routing table 115, and the packet of the subnetwork address C has the relay destination port of E. Therefore, the IP packet is routed to the port E112. The IP packet transmitted from the port E112 is transferred to the port W121 of the node device 120 via the transmission line 151.
Received by. The routing unit 124 refers to the routing table 125, and since the packet of the sub-network address C has the relay destination port E, it routes this IP packet to the port E122.
The IP packet sent from the port E122 is the transmission path 1
It is received by the port W 141 of the node device 140 via 52. The routing unit 144 refers to the routing table 145, recognizes that the IP packet whose destination address is C1 is addressed to its own node device, and fetches this IP packet in its own node device 140.

Next, the second conventional example will be described. FIG. 7 is a block diagram showing a method for constructing a packet communication network described in the above-mentioned JP-A-9-162925. In FIG. 7, the E side M port and the S port of the node device F are connected to the W side M port and the S port of the node device H, respectively, and the E side M port and the S port of the node device H are the node device G, respectively. Is connected to the W side M port and S port. Each node device F, G, H, I, J
Has an E-side port and a W-side port, each of which is composed of one M port and one or more S ports. Each node device
A packet received by the W-side M port is routed and transmitted to the E-side M port and S port, and a packet received by the E-side M port is routed and transmitted to the W-side M port and S port. Also, the packets received by the S ports on the W side and the E side are discarded without being routed. Finally, if the received packet is addressed to the own node device, the packet is taken into the own node device without being routed.

Next, referring to FIGS. 7 and 8 together, the procedure for adding the node devices I and J to the network composed of the node devices F, G, and H will be described.
As shown in FIG. 8, when the node device I is added, the E-side S port of the node device F and the W-side M port of the node device I are connected, and the W-side S port of the node device H and the node are connected. Connect to the E side M port of device I. When adding the node device J, the E-side S port of the node device H and the W-side M port of the node device J are connected so that the W-side S port of the node device G and the E-side M port of the node device J are connected. Connect to the port.

This method does not require a procedure of changing the address of the node device or updating the routing table. For example, when the packet of the destination address G is received by the W side M port of the node device F, the node device F routes this packet to the E side M port and the E side S port. The packet transmitted from the E side S port of the node device F is received by the W side M port of the node device I. The packet received by the W side M port of the node equipment I is routed to the E side M port of the node equipment I, and this packet is transmitted by the W side of the node equipment H.
Since it is received by the side S port, it is discarded. on the other hand,
The packet transmitted from the E side M port of the node device F is received by the W side M port of the node device H. The packet received by the W side M port of the node device H is routed to the E side M port and the E side S port of the node device H. The packet transmitted from the E side S port of the node device H is received by the W side M port of the node device J. The packet received by the W side M port of the node device J is routed and transmitted to the E side M port of the node device J. Since this packet is received by the W side S port of the node device G, it is discarded. It
Finally, the packet transmitted from the E-side M port of the node device H is received by the W-side M port of the node device G, and since the destination address is the address G of the own node device, the node device G is not routed. Taken in.

As described above, in the first conventional example, the IP addresses are logically hierarchized according to the installation location, and the IP addresses are hierarchized using this hierarchized IP address.
In order to route the packet, it is necessary to allocate the IP address so that the hierarchical structure is always maintained correctly. Therefore, every time a new node device is added, the IP address of the node device is set in correspondence with the subnetwork address of the installation location, and the IP address of the existing node device is set.
There was a problem that the address also had to be changed.

Further, in the second conventional example, since the port of each node device does not have a hierarchical address,
There is a problem that it is not compatible with an IP network such as the currently mainstream Internet and cannot coexist with an IP network. Further, since the packet is transmitted to an unspecified large number of node devices, there is a problem that the utilization efficiency of the transmission line is lowered.

In order to solve the problems of the conventional packet communication network construction method as described above, the present inventors have recently proposed a packet communication network construction method using a pseudo sub-network (Japanese Patent Application No. Hei 10-135242). 10-127937 application).

FIG. 9 is a block diagram showing a packet communication network construction method proposed by the inventors in this Japanese Patent Application No. 10-127937. The packet communication network construction method shown in FIG. 9 constructs a packet communication network based on, for example, an IP network that transfers packets using an IP address. Referring to FIG. 9, the port E 212 of the node device 210 and the port W 221 of the node device 220 are connected by the transmission line 251, and the node device 220
Port E222 of the node device and port W231 of the node device 230
Are connected by a transmission line 252.

The node device 210 includes ports W211 and E212 for transmitting and receiving packets relayed by a transmission line and one or more ports S213. Node device 220
Is provided with ports W221, E222 and one or more ports S223 for transmitting and receiving packets relayed by the transmission path. The node device 230 includes ports W231, E232 and one or more ports S233 for transmitting and receiving packets relayed by the transmission path. The node device 240 is a port W24 that transmits and receives packets relayed by the transmission path.
1, E242 and one or more ports S243.
Each port has an address (for example, Z
1, Z2, D1, E1, etc.), the uppercase alphabetic characters at the beginning of each address represent the subnetwork address, and the numbers after that represent the host address.

In the IP network, the routing is performed using the IP addresses hierarchically arranged according to the installation location, so that the port having the same IP sub-network address is usually allowed to exist in another location beyond the routing section. Absent. However, the node devices 210 and 220
Since a sub-network (hereinafter referred to as a pseudo sub-network) that is not used for normal routing is used between the node devices 220 and 230, the same sub-network address "Z" is used among a plurality of node devices. . In the following, an address belonging to the pseudo sub-network will be called a pseudo address.

The node device routes the packets received by the respective ports to the routing units 214, 224, 234 and 234.
244 to the appropriate port. The routing units 214, 224, 234 and 244 have routing tables 215, 225 and 23 inside, respectively.
5,245. Routing table 21
5, 225, 235, and 245 hold correspondence information between the destination address (“reception address” in FIG. 9) and the routing destination port (“relay destination port” in FIG. 9) of the received packet. Then, the routing units 214, 224, 234 and 244 route the packet to the corresponding port based on this correspondence information. If this packet is addressed to the own node device, it is taken into the own node device. Note that the routing information whose reception addresses in the routing tables 215, 225, 235, and 245 are other than the pseudo addresses Z1 and Z2 are automatically described by using a protocol such as RIP that dynamically constructs the routing table. It Further, the routing information whose reception addresses are the pseudo addresses Z1 and Z2 is fixedly set, and RI
The presence of the ports whose addresses are set to Z1 and Z2 is not notified or changed by P to other node devices.

The routing information in which the host address of the received address is "x" indicates the relay destination to the sub-network and is used when the host address is not included in the routing table. That is, in the routing table 215, the packet having the reception address D1 is taken into the own node device, but the other packets having the subnetwork address D are routed to the port S (port S213).

Next, with reference to FIG. 9, FIG. 10, and FIG. 11 together, the procedure for adding the node device 240 to the packet communication network constructed by the node devices 210, 220, 230 will be described.

When the node device 240 is added between the node device 210 and the node device 220, as shown in FIG. 10, the right end of the transmission line 251 is changed from the port W221 of the node device 220 to the port W241 of the node device 240.
To the node device 24 by a new transmission line 253.
0 port E242 and node device 220 port W22
Connect with 1.

When the node device 240 is added between the node device 220 and the node device 230, as shown in FIG. 11, the right end of the transmission line 252 is changed from the port W231 of the node device 230 to the port W241 of the node device 240.
To the node device 24 by a new transmission line 253.
0 port E242 and node device 230 port W23
Connect with 1.

After the node device 240 is added, the received address in the routing table is the pseudo address Z.
The routing information other than 1 and Z2 is updated to the latest routing information by RIP.

As described above, whether the node device 240 is added between the node device 210 and the node device 220 or the node device 240 is added between the node device 220 and the node device 230, the address by the administrator Setting is not required.

Next, referring to FIG. 11, the node device 24
The packet routing after adding 0 will be described.

Node devices 210, 220, 230, 24
The ports W211, W221, W231, W241 of 0 and the ports E212, E222, E232, E242 have pseudo addresses Z not used for normal routing.
2, Z1 is given. Therefore, the pseudo addresses Z2, Z1 are assigned to the node devices 210, 220, 230,
240 and the node device 210, 220, 230, 240 can be used as the destination address of the packet only by the terminal directly connected (without passing through another node device) to the port S of the other node. It is not used by the device or terminal as the destination address of the packet. In normal packet routing, each node device is designated as a packet destination by using the address of the port S that is not a pseudo address.

For example, in FIG. 11, the node device 21
In order for a terminal connected to the port S113 of 0 to send a packet to the node device 230, this terminal sets the destination address of the packet to be sent to the node device 230.
Address (F1) of the port S233.

The packet received by the port S113 of the node device 210 is sent to the port E2 by the routing unit 214 based on the information in the routing table 215.
12 is routed. The packet transmitted from the port E212 is transmitted to the node device 220 via the transmission line 251.
Is received by the port W221. The packet received by the port W221 is stored in the routing table 22.
Based on the information of No. 5, the routing unit 224 routes the data to the port E222. The packet transmitted from the port E222 is transmitted to the node device 2 via the transmission line 252.
40 port W241 is received. Port W24
The packet received by 1 is routed to the port E242 by the routing unit 244 based on the information in the routing table 245. The packet transmitted from the port E242 is received by the port W231 of the node device 230 via the transmission path 253. Port W
Based on the information in the routing table 235, the routing unit 234 recognizes that the packet received by the node 231 is addressed to the own node device, and the node device 2
It is taken in 30.

When a specific server is arranged in the node device (for example, the node device 210, 230) located at the end point of the linear pseudo sub-network Z as described above, Pseudo address Z
It is possible to transmit a packet in which 1 and Z2 are designated as the destination address. In the following, packet routing using a pseudo address to a server provided at the end of the pseudo sub-network will be described.

As shown in FIG. 11, the routing tables 215, 225, 235 and 245 have routing information when the destination addresses of the received packets are Z1 and Z2. This, as explained earlier,
It is changed by a protocol that dynamically updates the routing information such as RIP, and the address is changed to another node device by Z.
The routing information does not notify the existence of the ports set to 1 and Z2. Node devices other than the node device serving as the end point (node devices 220, 24
In the routing table 0), the routing information is described so that the destination address of the received packet is Z1 and the destination address is Z2, and the destination address is Z2, the route is to port E.

The node devices 210 and 230 which are the end points are
Packets whose destination addresses are pseudo addresses Z1 and Z2 can be captured. The node device 210 fetches the packet of the destination address Z1 and
It is possible to capture the packet of the destination address Z2 by 0 by describing the routing information for the reception addresses Z1 and Z2 of the routing tables 215 and 235 as “self”.

A specific server is a pseudo-subnetwork Z
Node device (node device 210, 230) that is the end point of the
The node devices 210, 220, 2
30, 240 and node devices 210, 220, 23
The terminal directly connected to the port S of 0 or 240 (without passing through another node device) transmits the packet to this server by the address D1, which is changed according to the installation location.
It is possible to use the pseudo addresses Z1 and Z2 that are not changed, instead of the E1 or the like.

For example, in FIG. 11, the node device 24
When a terminal connected to port S243 of 0 accesses the node device 210 that is a server, this terminal sends a packet whose destination address is the pseudo address “Z1” to port S243 of the node device 240. The packet received by the port S243 is routed by the routing unit 244 based on the information in the routing table 245.
Is routed to port W241. Port W
The packet transmitted from 241 is received by the port E222 of the node device 220 via the transmission line 252.
The packet received by the port E222 is routed by the routing unit 22 based on the information in the routing table 225.
4 is routed to port W221. The packet transmitted from the port W221 is received by the port E212 of the node device 210 via the transmission line 251. The packet received by the port E 212 is recognized by the routing unit 214 based on the information in the routing table 215, and is received in the node device 210.

In the above description, the case where the fourth node device is added to the three node devices has been described, but the number of node devices is not limited, and the packet communication network construction method described above is an IP network. The present invention is not limited to the above-mentioned application, but can be applied to all packet communication networks using addresses hierarchically arranged according to the installation location.

As described above, Japanese Patent Application No. 10-127937
According to the packet communication network construction method proposed by the present inventors in the No. application, a pseudo sub-network and a pseudo address not used for normal routing are used, and the same port is used for each node device connected by the pseudo sub-network. Since the pseudo addresses (Z1, Z2) having the pseudo sub-network address (Z) are fixedly provided, when the node device is added to the packet communication network, the address of the port of the node device added by the administrator is set at the installation location. It is not necessary to individually set or change the port address of the existing node device according to the above, and it becomes possible to add the node device freely and easily.

When a specific server is provided in the node device located at the end of the pseudo sub-network, the same pseudo address (Z1 or Z2) is always designated as the destination address and the packet is transmitted to this server. Is possible. In this case, since the pseudo address is used as the server address and the fixed routing information of the pseudo address is described in the routing table, it is not necessary for the administrator to individually set the port address of the server according to the installation location. For example, at the time of manufacturing and shipping the server, if the addresses of the ports on the west side and the east side are set to Z2 and Z1 in a unified manner, it is not necessary to change the address and the server of the end point of the pseudo sub-network can be set. It can be installed.

Furthermore, since this packet communication network construction method uses hierarchical addresses for each port, the existing I
It is compatible with P networks and can coexist with existing IP networks. Furthermore, since it is not necessary to transmit a packet to an unspecified number of node devices as in the second conventional example, the transmission line can be effectively used with high utilization efficiency.

[0041]

However, this Japanese Patent Application No. 1
The packet communication network construction method by the present inventors of the application No. 0-127937 also has the following problems.

That is, a node device having a specific server function is added to the end points of a plurality of node devices linearly connected by the pseudo sub-network as described above, and this node device is simulated from other node devices. In order to be able to perform packet transmission using the address as the destination address, the network administrator must manually change the routing table of this added node device and the node device connected to this node device. It was For example, as shown in FIG. 9, the node device 2 as a server is provided on the right side of the node device 230 at the right end of the node devices 210, 220, 230 connected by the pseudo sub-network.
In order to add a packet 40 to each node device so that a packet in which the pseudo address Z2 is designated as the destination address can be transmitted to this server, the node device 23
0, the network administrator needs to manually change the relay destination port for the reception address Z2 in the routing table 235 from “self” to “E”, and the relay destination for the reception address Z2 in the routing table 245 of the node device 240. The network administrator had to manually change the port from "E" to "me". The reason is that in the routing table, the received address (destination address) is the pseudo address Z1, Z2.
This is because the relay destination port for the packet is fixed.

An object of the present invention is to solve the above problems, and when a node device is added to an end point of a packet communication network composed of a plurality of node devices linearly connected by a pseudo sub-network, the network administrator A packet communication network and packet communication that automatically updates the routing table without the need to manually change the routing table by using, and enables packet transmission using a pseudo address to the node device added to this endpoint. An object is to provide a network construction method and a node device of a packet communication network.

[0044]

A packet communication network construction method according to claim 1, wherein a plurality of node devices are connected by a pseudo sub-network having the same pseudo sub-network address, and each is connected to the pseudo sub-network. The east side port and the west side port of the node device are fixedly given a pseudo address which is a combination of the pseudo sub-network address and the host address indicating the east side / west side, and the east side port and the west side port to which the pseudo address is given Whether or not the transmission path is connected to the transmission path is detected by the transmission path detection means in each node device, and the correspondence between the pseudo address in the routing table of the node device and the routing destination port is detected by the transmission path detection means. It is designed to be set based on the presence or absence of That.

The packet communication network construction method according to claim 2 is the packet communication network construction method according to claim 1,
When the connection of the transmission path to the east side port is detected by the transmission path detection means, the routing destination port for the pseudo address having the host address indicating the west side in the routing table is set to the east side port of the node device, When the connection of the transmission path to the east side port is not detected, the routing destination port for the pseudo address having the host address indicating the west side in the routing table is set in the node device, and the transmission path to the west side port is set. When a connection is detected, the routing destination port for the pseudo address having the host address indicating the east side in the routing table is set to the west side port of the node device, and the connection of the transmission line to the west side port is detected. If not It is obtained so as to set the routing destination port to the node device for pseudo-address that has a host address indicating the east side of the computing table.

The packet communication network construction method according to claim 3 is the packet communication network construction method according to claim 1 or 2, wherein the transmission path detecting means detects the presence or absence of connection of the transmission path. This is performed by detecting the packets reaching the port and the west side port.

A packet communication network construction method according to a fourth aspect is the packet communication network construction method according to any one of the first to third aspects, wherein the routing table has an address other than a pseudo address and a routing. The correspondence with the destination port is further retained.

A packet communication network construction method according to a fifth aspect is the packet communication network construction method according to the fourth aspect.
The correspondence between the address other than the pseudo address and the routing destination port in the routing table is RIP.
(Routing Information Prot
ocol).

A packet communication network according to a sixth aspect is a packet communication network including a plurality of node devices and a pseudo sub-network having the same pseudo sub-network address provided between the node devices. , The correspondence relationship between the east side port and the west side port in which the pseudo address, which is a combination of the pseudo subnetwork address and the host address indicating the east side / west side, is fixedly set, and the pseudo address and the routing destination port is held. A routing table, a routing means for routing a received packet to the node device to an appropriate port by referring to the routing table, and a transmission path detecting means for detecting whether or not a transmission path is connected to the east side port and the west side port And in the routing table The correspondence between the pseudo address and the routing destination port is obtained so as to have a pseudo-address routing destination port updating means for updating based on the presence or absence of connection of the transmission path detected by the transmission path detection unit.

A packet communication network according to a seventh aspect is the packet communication network according to the sixth aspect, wherein the pseudo address routing destination port updating means detects the connection of the transmission path to the east side port by the transmission path detecting means. In this case, set the routing destination port for the pseudo address that has the host address indicating the west side in the routing table to the east side port of the node device, and if the connection of the transmission path to the east side port is not detected, the routing table The routing destination port for the pseudo address having the host address indicating the west side is set in the node device, and when the connection of the transmission path to the west side port is detected, the host address indicating the east side in the routing table is set. The pseudo address Routing destination port to the west side port of the node device, and if the connection of the transmission line to the west side port is not detected, the routing destination port for the pseudo address that has the host address indicating the east side in the routing table Is set in the node device.

A packet communication network according to claim 8 is the packet communication network according to claim 6 or 7, wherein the transmission path detecting means detects the presence / absence of connection of the transmission path by the east side port and the west side port. This is performed by detecting a packet that reaches the.

A packet communication network according to a ninth aspect is the packet communication network according to any one of the sixth to eighth aspects, wherein the routing table includes addresses other than pseudo addresses and routing destination ports. The correspondence is further retained.

According to a tenth aspect of the packet communication network of the ninth aspect, in the packet communication network of the ninth aspect, the node device establishes a correspondence relationship between an address other than the pseudo address in the routing table and a routing destination port by RIP (Ro).
Uting Information Protocol
It further comprises RIP updating means for updating based on l).

A node device of a packet communication network according to claim 11 is a node forming a packet communication network including a plurality of node devices and a pseudo sub-network having the same pseudo sub-network address provided between the node devices. Correspondence between the east side port and the west side port, which is a device and has a fixed pseudo address that is a combination of the pseudo sub-network address and the host address indicating the east side / west side, and the pseudo address and the routing destination port And a routing table for holding the packet, routing means for routing the received packet to the node device to an appropriate port by referring to the routing table, and transmission for detecting the presence or absence of the connection of the transmission path to the east side port and the west side port. Road detection means and route Is obtained by a pseudo-address routing destination port updating means for updating based on correspondence between the pseudo address and the routing destination port in the grayed table of the presence or absence of connection of the transmission path detected by the transmission path detection unit.

A packet communication network node device according to a twelfth aspect is the node device of the packet communication network according to the eleventh aspect, wherein the pseudo address routing destination port updating means is a transmission path to the east side port by the transmission path detecting means. If the connection is detected, the routing destination port for the pseudo address having the host address indicating the west side in the routing table is set to the east side port of the node device, and the connection of the transmission line to the east side port is detected. If not, the routing destination port for the pseudo address that has the host address indicating the west side in the routing table is set in the node device, and if the connection of the transmission line to the west side port is detected, the east side in the routing table Host ad showing Set the routing destination port for the pseudo address that has the address to the west side port of the node device, and if the connection of the transmission path to the west side port is not detected, it has the host address indicating the east side in the routing table The routing destination port for the pseudo address is set in the node device.

A packet communication network node device according to a thirteenth aspect is the packet communication network node device according to the eleventh or twelfth aspect, wherein the transmission path detecting means detects whether or not the transmission path is connected by the east side port. And the packet reaching the west side port is detected.

A node device of a packet communication network according to a fourteenth aspect is the node device of a packet communication network according to any one of the eleventh to thirteenth aspects, wherein the routing table has an address other than a pseudo address and a routing. The correspondence with the destination port is further retained.

A node device of a packet communication network according to a fifteenth aspect is the node device of the packet communication network according to the fourteenth aspect, wherein a correspondence relationship between an address other than a pseudo address in a routing table and a routing destination port is RIP (Routing Information). P
RIP updating means for updating based on the protocol.

[0059]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing a packet communication network construction method according to an embodiment of the present invention. Referring to FIG. 1, the port E12 of the node device 10 and the node device 2
0 port W21 is connected by transmission line 51,
The port E22 of the node device 20 and the port W31 of the node device 30 are connected by a transmission line 52.

Each of the node devices 10, 20, 30, 40 has a port W11, W21, W31, W41 for transmitting / receiving a packet relayed by a transmission line, a port E12,
E22, E32, E42, and one or more ports S1
3, S23, S33, S43. Each port has an address (for example, Z1, Z2, D
1, E1, etc.), the uppercase alphabetic characters at the beginning of each address represent the subnetwork address, and the numbers after that represent the host address.

Ports W11, W21, W31, W41 of node devices 10, 20, 30, 40 and port E12,
E22, E32, and E42 have pseudo addresses (Z2 or Z1) that belong to the pseudo sub-network. Each of the node devices 10, 20, 30, 40 includes a routing unit 14, 24, 34, 44, and the routing unit 14,
24, 34 and 44 are the routing table 1 respectively.
The relay destination (routing destination) port of the received packet is determined by referring to 5, 25, 35, and 45, and the packet is routed to the routing destination port. Further, the node devices 10, 20, 30, 40 are respectively provided with transmission line detecting units 16, 26, 36, 46.

FIG. 2 shows each node device (eg node device 1
It is a block diagram which shows an example of a detailed internal structure of 0).
Each port of the node device 10 is composed of a line termination unit A and a framing detection unit B. The line terminating unit A physically terminates a transmission line such as an optical fiber or a conductor. The framing detection unit B recognizes the framing of the packet by performing processing according to the type of the packet to be transmitted and received. For example,
In the case of PPP and HDLC packets, IETF (In
internet Engineering Task F
RFC (Request for Co)
Mment) 1662, the ATM
In the case of a cell, the processing described in the "standard ATM textbook" (Ascii Publishing, 1995) is used, and in the case of an SDH frame, the "SDH transmission method" (Ohm, 1993).
In the case of the Ethernet frame, the processing described in (Year) is IEEE (Institute of E).
electrical & Electronics E
nginesers Inc) 802.3 to recognize the framing of the packet. The framing detection unit B of the port having the pseudo address (ports W11 and E12) supplies the framing detection signal to the transmission path detection unit 16. The other node devices 20, 3
0 and 40 are similarly configured.

Each node device 10, 20, shown in FIG.
The transmission line detection units 16, 26, 36, 46 of 30, 40 are
When receiving the framing detection signal from the framing detection unit B of the port having the pseudo address (west side port, east side port), it is recognized that the transmission line is connected to that port, and this signal must be received for a certain period of time. , Recognize that the transmission line is not connected to the port.

The transmission line detectors 16, 26, 36 and 46 respectively have waist side ports W11, W21, W31 and W.
When the transmission line is connected to 41, the relay destination port for the reception address (destination address) Z1 of the routing table 15, 25, 35, 45 is set to "W", and when the transmission line is not connected, , The relay destination port for the reception address (destination address) Z1 is “self”. In addition, the transmission path detectors 16, 26, 36, 46 respectively include east side ports E12, E22, E32, E4.
2 is connected to a transmission line, the relay destination port for the reception address (destination address) Z2 of the routing table 15, 25, 35, 45 is set to "E", and when the transmission line is not connected. , The relay destination port for the reception address (destination address) Z2 is “self”.

Next, referring to FIGS. 1 and 3 together, the node device 40 is provided at the right end point of the packet communication network constructed by the node devices 10, 20, and 30 linearly connected by the pseudo sub-network. The operation when adding is described.

First, referring to FIG. 1 showing the state before the node device 40 is added to the packet communication network, the transmission line detecting unit 36 of the node device 30 has the transmission line connected to the port W31. Since the relay destination port for the reception address Z1 in the routing table 35 is set to W and the transmission path is not connected to the port E32, the relay destination port for the reception address Z2 in the routing table 35 is set as itself. There is. Further, the transmission path detection unit 46 of the node device 40 uses the ports W41 and E4.
Since the transmission line is not connected to No. 2, the relay destination port for the reception addresses Z1 and Z2 of the routing table 45 is set to itself.

Next, the node device 40 is connected to the right side of the node device 30. As shown in FIG. 3, when the node device 40 is added, the administrator connects the port E32 of the node device 30 and the port W41 of the node device 40 by the new transmission line 53.

The transmission path detection unit 36 of the node device 30 detects that the transmission path is connected to the port E32 by the above-mentioned processing, and the reception address Z of the routing table 35 is detected.
The relay destination port for No. 2 is updated from "self" shown in FIG. 1 to "E" shown in FIG. In addition, the node device 4
The transmission path detecting unit 46 of 0 detects that the transmission path is connected to the port W41 by the above-described processing, and the relay destination port for the reception address Z1 of the routing table 45 is changed from “self” shown in FIG. 3 is updated to "W".

The routing tables 15, 25,
The routing information for the reception addresses other than the pseudo addresses Z1 and Z2 of 35 and 45 is, for example, IETF (In
internet Engineering Task F
RFC (Request for Com)
RIP specified in 1058, 1723
(Routing Information Prot
It is automatically updated by a protocol that dynamically builds a routing table, such as the Ocol).

Next, the packet routing using the updated routing table will be described with reference to FIG.

For example, when the terminal connected to the port S13 of the node device 10 transmits the packet of the destination address Z2, the routing parts 14, 24, 34 of the node devices 10, 20, 30 are in order respectively. , Ports E12, E2 which are relay destination ports for the destination address Z2 of the received packet in the routing tables 15, 25, 35
2, this packet is relayed and transmitted to E32. The newly added node device 40 sends this packet to port W41.
Then, the routing unit 44 of the node device 40 recognizes that this packet is addressed to itself by referring to the routing table 45, and this packet is taken into the node device 40.

Further, for example, the port S4 of the node device 40
When the terminal connected to No. 3 transmits the packet having the destination address Z1, the routing units 44, 34, 24 of the node devices 40, 30, 20 receive the routing tables 45, 35, 25 in that order. Ports W41 and W that are relay destination ports for the destination address Z1 of the packet
The packet is relayed to 31 and W21 and transmitted. The node device 10 receives this packet at the port E12, and the routing unit 14 of the node device 10 recognizes that this packet is addressed to itself by referring to the routing table 15, and this packet is It is taken into the node device 10.

Further, for example, the port S4 of the node device 40
When the terminal connected to No. 3 transmits the packet of the destination address E1 which is not the pseudo address, the packet is transferred as follows. First, the routing unit 44 of the node device 40 routes this packet to the port W41 by referring to the routing table 45. The packet transmitted from the port W41 is transmitted by the transmission line 5
It is received by the port E32 of the node device 30 via Route 3. The packet received by the port E32 is routed by the routing unit 34 based on the information in the routing table 35.
Is routed to port W31. Port W3
The packet transmitted from 1 is received by the port E22 of the node device 20 via the transmission path 52. Port E2
The packet received by No. 2 is recognized by the routing unit 24 based on the information in the routing table 25 as being addressed to its own node device, and is taken into the node device 20.

In the above three examples, the case where the terminal connected to the south side port of the node device transmits a packet having the pseudo address or the address which is not the pseudo address as the destination address is shown. However, the south side port of the node device is shown. Even when the node device itself transmits the packet, not the terminal connected to the packet, the same routing is performed for the packet.

The case where the node device 40 is added to the end point of the packet communication network constructed by the linearly connected node devices 10, 20, 30 has been described above. Other than the end points, for example, between the node devices 10 and 20 or the node devices 20 and 30
Even when the node device 40 is added between the two, the relay destination ports for the pseudo addresses Z1 and Z2 of the routing table are updated based on the presence / absence of the transmission path connection by the transmission path detection unit in the same manner as above. Further, the routing information for the received addresses other than the pseudo addresses Z1 and Z2 is automatically updated by a protocol such as RIP that dynamically constructs a routing table.

As described above, according to the packet communication network construction method of the present embodiment, each node device is provided with the transmission path detecting unit, and based on the detection of the presence or absence of the connection of the transmission path by this transmission path detecting unit. Since the relay destination ports for the pseudo addresses Z1 and Z2 in the routing table are updated, a new node device is added between the node devices of the packet communication network composed of a plurality of node devices linearly connected by the pseudo sub-network. In addition to the case where the node device is newly added to the end point of the packet communication network, the routing table is automatically updated without the need for the network administrator to manually change the routing table. It is possible to send a packet using a pseudo address to the node device added to Therefore, the network administrator can easily add the node device to any position of the packet communication network linearly connected by the pseudo sub-network.

Further, since the packet communication network construction method of the present embodiment uses the hierarchical address for each port, it is compatible with the existing IP network and the existing I network.
It is possible to coexist with a P network. Furthermore, since it is not necessary to transmit a packet to an unspecified number of node devices as in the second conventional example, the transmission line can be effectively used with high utilization efficiency.

Although the case where the fourth node device is added to the three node devices has been described above, the number of node devices is not limited, and the packet communication network construction method described above is an IP network. The present invention is not limited to the above-mentioned application, but can be applied to all packet communication networks using addresses hierarchically arranged according to the installation location.

[0080]

As described above, according to the packet communication network construction method of the first aspect, a plurality of node devices are connected by a pseudo sub-network having the same pseudo sub-network address, and are connected to the pseudo sub-network. The east side port and the west side port of each of the node devices are fixedly given a pseudo address that is a combination of the pseudo sub-network address and the host address indicating the east side / west side, and the east side port and the east side port to which the pseudo address is given. Whether or not the transmission path is connected to the west side port is detected by the transmission path detection means in each node device, and the correspondence between the pseudo address in the routing table of the node device and the routing destination port is detected by the transmission path detection means. Changed to set based on whether or not the road is connected Therefore, when adding a node device to the packet communication network, the administrator must set the port address of this node device individually according to the installation location or change the port address of the existing node device. It is possible to add a node device freely and easily. Further, by providing a specific server in the node device located at the end point of the pseudo sub-network, it is possible to always send packets to this server in which the same pseudo address is designated as the destination address. Furthermore, since hierarchical addresses are used for each port, it is compatible with existing IP networks and can coexist with existing IP networks. Further, since it is not necessary to transmit the packet to an unspecified number of node devices, it is possible to effectively use the transmission path with high utilization efficiency. In addition to this, according to the addition / deletion of the node device, the pseudo network in the routing table is automatically detected based on the detection of the connection of the transmission path by the transmission path detection means without requiring the manual change by the network administrator. It becomes possible to update the routing destination port for the address.
Therefore, for example, even when a node device is added to the end points of a plurality of node devices linearly connected by the pseudo sub-network, the pseudo in the routing table is automatically changed without the need for manual change by the network administrator. The routing destination port for the address is updated, and it is possible to transmit the packet using the pseudo address to the node device added to this end point.

According to the packet communication network constructing method of the second aspect, in the packet communication network constructing method of the first aspect, when the connection of the transmission path to the east side port is detected by the transmission path detecting means, the routing is performed. Set the routing destination port for the pseudo address that has the host address indicating the west side in the table to the east side port of the node device, and if the connection of the transmission path to the east side port is not detected, the west side in the routing table If a routing destination port for a pseudo address having a host address indicating that is set in the node device and connection of the transmission line to the west side port is detected, a pseudo address having a host address indicating the east side in the routing table is set. The destination port for the address Node to the west side port of the node device, and when the connection of the transmission line to the west side port is not detected, the routing destination port for the pseudo address having the host address indicating the east side in the routing table is set to that node. Since the setting is made in the device, when a transmission line is connected to the east side port of each node device, the routing destination port for the pseudo address having the host address indicating the west side in the routing table of that node device is the node The device automatically updates to the east side port of the node device, and when the transmission line is removed from the east side port of each node device, the pseudo with the host address indicating the west side in the routing table of the node device Address When the routing destination port is automatically updated from the east side port of the node equipment to the node equipment and the transmission line is connected to the west side port of each node equipment, the east side in the routing table of the node equipment is shown. The routing destination port for the pseudo address having the host address is automatically updated from the node device to the west side port of the node device, and when the transmission line is removed from the west side port of each node device, the node device The routing destination port for the pseudo address having the host address indicating the east side in the routing table of is automatically updated from the west side port of the node device to the node device, and network management is performed according to the addition / deletion of the node device. Changes manually It is possible to automatically update the routing destination port for the pseudo address in the routing table without the need for. Therefore, for example, even when a node device is added to the end points of a plurality of node devices linearly connected by the pseudo sub-network, the pseudo in the routing table is automatically changed without the need for manual change by the network administrator. The routing destination port for the address is updated, and it is possible to transmit the packet using the pseudo address to the node device added to this end point.

According to the packet communication network construction method of claim 3, in the packet communication network construction method of claim 1 or 2, the transmission line detecting means detects whether or not the transmission line is connected. Since the detection is made by detecting the packet reaching the east side port and the west side port, the routing related to the east side port or the west side port in the routing table is conditioned on the arrival of the packet at the east side port or the west side port. There is an effect that information can be updated.

According to the packet communication network construction method of claim 4, in the packet communication network construction method of any one of claims 1 to 3, the routing table is an address other than a pseudo address. Since the correspondence relationship between the destination address and the routing destination port is further held, there is an effect that packet communication using a normal address other than the pseudo address can be performed as the destination address.

According to the packet communication network construction method of the fifth aspect, in the packet communication network construction method of the fourth aspect, the correspondence relation between the address other than the pseudo address in the routing table and the routing destination port is RI.
P (Routing Information Pro)
Since all the addresses including the pseudo address and the normal address in the routing table and the routing destination port are automatically updated, the correspondence relationship can be automatically updated.

According to the packet communication network described in claims 6 to 10, the same effects as those obtained by the packet communication network construction method described in claims 1 to 5 can be obtained.

According to the node device of the packet communication network of the eleventh to fifteenth aspects, the same effects as those obtained by the packet communication network construction method of the first to fifth aspects are obtained, respectively.

[Brief description of drawings]

FIG. 1 is a block diagram showing a method for constructing a packet communication network according to an embodiment of the present invention.

2 is a block diagram showing an example of a detailed internal configuration of each node device in the packet communication network construction method of FIG.

3 is a block diagram showing an operation when a node device is added to an end point in the packet communication network construction method of FIG.

FIG. 4 is a block diagram showing a conventional packet communication network construction method using an IP network.

5 is a block diagram showing an operation when a node device is added between two node devices in the conventional packet communication network construction method of FIG.

6 is a block diagram showing an operation when a node device is added between two other node devices in the conventional packet communication network construction method of FIG.

FIG. 7 is a block diagram showing a conventional packet communication network construction method described in JP-A-9-162925.

8 is a block diagram showing an operation when a node device is added in the conventional packet communication network construction method of FIG.

FIG. 9 is a block diagram showing a packet communication network construction method proposed by the inventors in the Japanese Patent Application No. 10-127937 application.

10 is a block diagram showing an operation when a node device is added between two node devices in the packet communication network construction method of FIG.

11 is a block diagram showing an operation when a node device is added between two other node devices in the packet communication network construction method of FIG. 9.

[Explanation of symbols]

10, 20, 30, 40 Node device 14, 24, 34, 44 Routing unit (routing means) 15, 25, 35, 45 Routing table 16, 26, 36, 46 Transmission path detection unit (transmission path detection means) 51, 52, 53, 54 Transmission lines W11, W21, W31, W41 West side ports E12, E22, E32, E42 East side port Z Pseudo sub-network Z1, Z2 Pseudo address

Claims (15)

(57) [Claims] 1. A plurality of node devices are connected by a pseudo subnetwork having the same pseudo subnetwork address, and the pseudo subnetwork is connected to an east side port and a west side port of each of the node devices connected to the pseudo subnetwork. A pseudo address, which is a combination of a network address and a host address indicating the east side / west side, is fixedly provided, and the presence / absence of connection of a transmission path to the east side port and the west side port to which the pseudo address is given is described above. Detected by the transmission path detection means in each node device, the correspondence between the pseudo address and the routing destination port in the routing table of the node device is based on the presence or absence of the connection of the transmission path detected by the transmission path detection means. Packet communication characterized by setting Network construction method. 2. When the connection of the transmission line to the east side port is detected by the transmission line detecting means, a routing destination port for the pseudo address having the host address indicating the west side in the routing table is set. It is set to the east side port of the node device, and when the connection of the transmission path to the east side port is not detected, the routing destination port for the pseudo address having the host address indicating the west side in the routing table Is set to the node device, and when the connection of the transmission path to the west side port is detected, the routing destination port for the pseudo address having the host address indicating the east side in the routing table is set to the node. Equipment Node side device, and if the connection of the transmission line to the west side port is not detected, the routing destination port for the pseudo address having the host address indicating the east side in the routing table is set as the node device. The packet communication network construction method according to claim 1, wherein 3. The transmission line detecting means detects whether or not the transmission line is connected by detecting a packet reaching the east side port and the west side port. The packet communication network construction method described. 4. The routing table further holds a correspondence relationship between an address other than the pseudo address and a routing destination port.
The method for constructing a packet communication network according to any one of 1. 5. A correspondence relationship between an address other than the pseudo address and a routing destination port in the routing table is RIP (Routing Information).
5. The packet communication network construction method according to claim 4, wherein the packet communication network construction method is updated. 6. A plurality of node devices, and a pseudo sub-network having the same pseudo sub-network address provided between the node devices, wherein the node device comprises the pseudo sub-network address and the east side / west side. The east side port and the west side port in which a pseudo address, which is a combination of host addresses, is fixedly set, a routing table that holds a correspondence relationship between the pseudo address and a routing destination port, and the routing table is referred to. A routing means for routing a received packet to the node device to an appropriate port, a transmission path detecting means for detecting the presence / absence of a connection of a transmission path to the east side port and the west side port, and in the routing table The pseudo ad Packet communication network, characterized in that it comprises a pseudo-address routing destination port updating means for updating, based scan and the correspondence between the routing destination port of whether the connection of the transmission path detected by the transmission path detection unit. 7. The pseudo address routing destination port updating means sets the host address indicating the west side in the routing table when the transmission path detecting means detects the connection of the transmission path to the east side port. The routing destination port for the pseudo address that has been set to the east side port of the node device, and when the connection of the transmission path to the east side port is not detected, the host address indicating the west side in the routing table The routing destination port for the pseudo address having the is set in the node device, and when the connection of the transmission path to the west side port is detected, the host address indicating the east side in the routing table is provided. Pair with pseudo address The routing destination port to be set to the west side port of the node device, and when the connection of the transmission line to the west side port is not detected, the pseudo having the host address indicating the east side in the routing table 7. The packet communication network according to claim 6, wherein a routing destination port for the address is set in the node device. 8. The transmission line detecting means detects whether or not the transmission line is connected by detecting a packet reaching the east side port and the west side port. The packet communication network described. 9. The routing table further holds a correspondence relationship between an address other than the pseudo address and a routing destination port.
The packet communication network according to any one of 1. 10. The node device determines a correspondence relationship between an address other than the pseudo address in the routing table and a routing destination port by RIP (Router).
10. The packet communication network according to claim 9, further comprising RIP updating means for updating based on ng Information Protocol). 11. The node device forming a packet communication network comprising a plurality of node devices and a pseudo sub-network having the same pseudo sub-network address provided between the node devices, wherein the pseudo sub-network address And a east side port and a west side port in which a pseudo address that is a combination of host addresses indicating the east side / west side is fixedly set, and a routing table that holds the correspondence relationship between the pseudo address and the routing destination port, Routing means for routing a received packet to the node device to an appropriate port by referring to the routing table, and transmission path detecting means for detecting the presence / absence of connection of a transmission path to the east side port and the west side port And said routing And a pseudo address routing destination port updating means for updating the correspondence between the pseudo address and the routing destination port in the table based on the presence or absence of the connection of the transmission path detected by the transmission path detecting means. Node device of a packet communication network that performs communication. 12. The pseudo address routing destination port updating means sets the host address indicating the west side in the routing table when the transmission path detecting means detects the connection of the transmission path to the east side port. The routing destination port for the pseudo address that has been set to the east side port of the node device, and when the connection of the transmission path to the east side port is not detected, the host address indicating the west side in the routing table The routing destination port for the pseudo address having the is set in the node device, and when the connection of the transmission path to the west side port is detected, the host address indicating the east side in the routing table is provided. To a pseudo address The corresponding routing destination port is set to the west side port of the node device, and when the connection of the transmission line to the west side port is not detected, the pseudo having the host address indicating the east side in the routing table The node device of the packet communication network according to claim 11, wherein a routing destination port for the address is set in the node device. 13. The transmission line detecting means detects the presence or absence of connection of the transmission line by detecting a packet reaching the east side port and the west side port. A node device of the described packet communication network. 14. The packet communication according to claim 11, wherein the routing table further holds a correspondence relationship between an address other than the pseudo address and a routing destination port. Network node equipment. 15. A correspondence relationship between an address other than the pseudo address and a routing destination port in the routing table is defined by RIP (Routing Information).
R based on the
15. The apparatus according to claim 14, further comprising IP updating means.
A node device of the described packet communication network.