JPH02116241A - Packet exchanging network constituting system - Google Patents

Abstract

PURPOSE:To improve the reliability of a tree-shaped network for the trouble of the exchange module of a route by arranging plural exchange switch modules which become the route of the tree-shaped network, dispersing and arranging the exchange modules and connecting with a line mutually. CONSTITUTION:Four exchange modules 1 to 4 of the route are provided, respective exchange modules are mutually connected completely in a mesh shape, exchange modules 100 to 400 are connected under respective exchange modules 1 to 4 and a subscriber is connected under these exchange modules. When an exchange module 1 receives the data, for example, from an exchange module 100 to an exchange module 300, ordinarily, the exchange module 2 transmitted through a line l9 to an exchange module 2 is transmitted to the exchange module 300 by the line l9. Thus, for example, even when the exchange module 2 becomes a trouble, the communication between exchange modules 100, 200 and 400 can be carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a packet switching system, and particularly to a method for improving the reliability of a network in which switch modules are arranged in a tree shape.

[Conventional technology]

Conventionally, when configuring a large-scale network by combining switch modules made up of binary switches in a tree shape, the configuration was such that there was only one switch module serving as the root of the tree-like network. .

In addition, this type of tree-like network is described in Information Processing Society of Japan Vo Q, 27, Nu9, PP
1005-1-021. Furthermore, regarding a system that enables high-speed switching by combining binary switches in multiple stages, Japanese Patent Laid-Open No. 61-849
No. 42.

and Japanese Unexamined Patent Publication No. 61-84943.

[Problem to be solved by the invention]

The above conventional technology does not take into account failures in the root exchange module in a network that connects binary switches in a tree, and if a failure occurs in the exchange module, all data passing through it cannot be exchanged. There was a problem with it disappearing.

The present invention solves the above-mentioned conventional problems, and the tree-like net 1-
In a work, it is possible to install two or more exchange modules that serve as the root, so that even if one of the root exchange modules fails, all data via the root exchange module cannot be exchanged. The aim is to reduce the impact of the above-mentioned obstacles.

[Means for solving the problem] Two or more modules are set and all of these exchangeable modules can be connected to a complete mesh structure.

Furthermore, in order to be able to respond to failures in the line connecting the root exchange module, a failure detection function for the line and a function for sending data sent to that line when a failure is detected to other lines are provided. It also has a function to detect the congestion state of the line connecting the root exchange module, and a function to send data to other lines when congestion is detected.

[Effect]

In the binary switch exchange process in the exchange module,
The status of the internal F'IFO (first-in-first-out) buffer of the next binary switch to be transferred is monitored using the control line, and data is sent only when there is space, and when there is no space,
Data is held in internal FIF○. Thereby, there is no loss of data due to collisions or buffer overflows. In addition, communication between exchange modules at the root of a tree-like network always follows a unique route once the destination exchange module is determined, so there is no reversal of the order of transmitted data and highly reliable packet transmission・You can transfer data.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of a network in which the present invention is implemented, as a combination of exchange modules. Switching modules 1-4 correspond to the root switching module 1000 in the conventional tree-like network shown in FIG.

In the present invention, as shown in the example of FIG. 1, four root exchange modules 1 to 4 are provided, and the respective exchange modules are interconnected in a complete mesh configuration. Below each exchange module 1 to 4 are exchange modules 100, 200, 3.
00,400 are connected. Subscribers are connected below these switching modules. When the switching module 1 receives data addressed to the switching module 300 from the switching module 100, for example (hereinafter, the term data is used to mean a packet in a packet switching system),
Normally, it is sent to exchange module 2 via line Q1. Switching module 2 transmits to switching module 300 over line Q9. Similarly, exchange module 1 transfers data from exchange module 100 to exchange module 200.
When data is to be sent to the switching module 4, it is sent to the exchange module via the line Q3, and when data from the exchange module 100 is to be sent to the exchange module 4, it is sent via the line Q2. Therefore, in the configuration according to the present invention, even if, for example, exchange module 2 becomes a failure, communication between exchange modules 100, 200, and 400 is possible.

FIG. 2 shows an example in which the configuration of FIG. 1 is configured with the binary switch shown in FIG. 4.

As shown in Figure 4, a binary switch determines a specific bit in a bit string that indicates an address in input data, and selects the line to send based on whether the value of that bit is 0 or 1. This is a switch to

Referring to FIG. 2, a description will be given of a data transfer operation from exchange module 100 to exchange module 300. Note that in FIG. 1, the line is shown using one line, but in FIG. 2, the line is shown as two lines with opposite directions to make the direction of data clear.

In addition, in FIG. 2, the connection between the root exchange module and the lower exchange module is shown in detail only between exchange modules 1 and 100, but the connection between other exchange modules, that is, the exchange Also exchange modules 1 and 1 between modules 4 and 400.3 and 200, and 2 and 300.
This is the same connection as between 00 and 00. Now, exchange module 1
The data (destination address [10]) sent from 00 to switching module 1 via line Q7 is transferred to line Q50 because the first bit of the destination address is determined by the first binary switch and is 1. is sent to the next binary switch.

The next binary switch is the second bit 1 of the destination address.
Since it is O, it is transmitted to line ρl. As a result, the data is sent to the exchange module 2. In exchange module 2, like exchange module 1, the first binary switch selects the first pin 1- of the destination address.
The next binary switch determines the second bit and the result is sent to the exchange module 300. The same applies to data from exchange module 100 to exchange module 200 and from exchange module 100 to exchange module 4.0O. Furthermore, communications between other exchange modules are exchanged by binary switches in exactly the same way.

In the present invention, it is not necessary to set the number of root exchange modules corresponding to the number of branches in this structure. One example is shown in Figure 5, in which case,
There are two root exchange modules, each connected to two lower order exchange modules. In this case, for example, if a failure occurs in the exchange module on the route to which exchange modules 300 and 400 are connected, only communication between exchange modules 100 and 200 will continue.

FIG. 6 shows another embodiment of the invention. FIG. 6 shows only those parts of FIG. 2 that are necessary for explaining the present invention. In this embodiment, a device 1 has a line fault detection function and a function of detouring data to be sent to the faulty line to another line.
This is realized by 000. Line fault detection is done using HD L
C (High 1evelData Link Co
This can be realized using a high-speed digital line interface, etc. Further, a multiplexing method for detouring data to another line can be realized by a normal packet multiplexing method.

In FIG. 6, it is shown using an example that communication is possible even if a failure occurs in the line between the switching modules 1 to 4 of the route. Suppose now that a failure occurs on line Q5.

Consider the case where data is transmitted from exchange module 400 to exchange module 200. If no fault has occurred on the line Q5, the message is transmitted to the exchange module 3 using this line.

When the device 1000 detects a failure in line Q5,
5, bypass the data sent to 5 as indicated by the dotted line 1001,
Send to line Q6. Therefore, data sent to the exchange module 3 is first sent to the exchange module 2. Similar to the data sent from the switching module 300 to the switching module 200, the data sent to the switching module 2 is transferred to the line 1 based on the determination of the two-stage binary switch.
24 and is sent to the exchange module 3. The data that has arrived at the exchange module 3 is determined by the two-stage binary switch as described above, and is transferred to the exchange module 20.
Sent to 0.

In the above example, when a failure occurs in line Q5, the detour is made to line Ω6, but even if the detour is made to line I22, it is sent to line Q3 based on the judgment of the two-stage binary switch in exchange module 1, and the line It is sent to exchange module 3 in the same way as when it is detoured to Q6.

Above, we have explained how to detour data sent from the exchange module 4 to the exchange module 3 in the event of a failure in the line Ω5.
If a failure occurs in line Q2 and line Q6 when transmitting from to switching module 1 or switching module 2, even if a detour is made to another line, line Q5
It is possible to continue communication as if a failure had occurred. Further, when transmitting data from other exchange modules 1 to 3 to another exchange module, even if a failure occurs in the transmission line, communication can be continued by detouring the data in the same way.

〔Effect of the invention〕

According to the present invention, a plurality of root exchange modules can be provided in a network in which exchange modules of binary switches are configured in a tree shape, and the reliability of the tree-like network is improved against a failure of the root exchange module. be able to. Furthermore, since a detour can be taken in the event of a failure in the line connecting the root exchange modules, the reliability of the tree-like network can be improved even in the event of a line failure. Further, since it is possible to take a detour when the width of the line connecting between the root exchange modules is shortened, it is possible to improve the performance of the tree-like network.

[Brief explanation of the drawing]

Fig. 1 is a conceptual diagram of the structure of a tree-like network that implements the present invention, Fig. 2 is a diagram of the line connection structure when the above network is realized by an exchange module composed of binary switches, and Fig. 3 is a diagram of the conventional structure. FIG. 4 is a conceptual diagram showing the operation of a binary switch; FIG. 5 is a configuration diagram of another embodiment of the present invention in which two root exchange modules are used; FIG. 6 is a connection configuration diagram showing still another embodiment of the present invention. . 1~4...Replacement module for Ru 1~, 1000...
・Root exchange module, 100-400... Exchange module, Q] ~ flo... Line, 701,70
5...Subscriber.

Claims (1)

[Scope of Claims] 1. In a switching network system configured by hierarchically connecting modules of switching switches composed of binary switches in multiple stages in a tree shape, the switching switch module serving as the root of the tree-like network; 1. A configuration method for a packet switching network, characterized in that a plurality of one of the above are installed, and the switching modules are arranged in a distributed manner so that they can be connected to each other using lines. 2. For each exchange module of the plurality of routes,
2. The method of configuring a packet switching network according to claim 1, further comprising a function of detecting a fault in a line that interconnects these lines, and a function of detouring to one of the other lines when the fault is detected. 3. For each exchange module of the plurality of routes,
The configuration of the packet switching network according to claim 1, characterized in that it is provided with a function of detecting a congestion state of a line that interconnects them, and a function of detouring to any of the other lines when the congestion state is detected. method.