JPH04160949A - Switching unit - Google Patents

Abstract

PURPOSE:To make it possible to obtain an economical redundant configuration of a switching unit by connecting one in line to a plurality of unit switches at the input side, by connecting one out line to a plurality of unit switches at the output side, by closing, in the case trouble occurs, only a unit switch in trouble, and by making a cell passing through the relevant switch detour another link. CONSTITUTION:In the normal condition, a call cell goes out to a target out line through either one of unit switches 100-181 at the first stage, unit switches 200-281 at the second switches, and unit switches 300-381 in accordance with preset path information. In the case unit switches at the first stage where in lines are housed or those at the last stage where out lines are housed fail, in lines and out lines are connected to substitutive unit switches. Although when cells passing through unit switches in trouble are detoured to other switches, traffic of those substitutive unit switches is congested, this problem is dealt with by raising link speed of those unit switches to a value greater than line speed.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to an ATM (Asynchronous Tr).
It is used in the switch circuit network of the answer mode) method. In particular, it relates to a redundant configuration when a failure occurs in a switch network.

〔overview〕

The present invention provides an economical redundant configuration in a redundant configuration means for an asynchronous transmission mode switch network of a switching device by detouring a call passing through a faulty switch via another link. It has been made possible.

[Conventional technology]

In the conventional example, it was common to duplicate identical switch circuit networks, and when a failure occurred in one switch network, the entire network was switched to the other switch network. The configuration of this conventional example is shown in FIG. In this example, there are two three-stage switch networks, a 0-system switch network 20 and a 1-system switch network 21.
It is comprised of a switching circuit 3 that selects which one to use, and a switching control circuit 4 that instructs switching. now,
Assuming that the 0-system switch network 20 is used for communication as the active system, the 1-system switch network 2
1 is used as a standby system. here,
If a failure occurs in one of the multiple switches in the 0-system switch network 2Ω, all
A switching instruction is issued from the switching control circuit 4 to the switching circuit 3 to switch the outgoing line to the 1-system switch network 21, and then,
A fault search for the 0-system switch network 20 is performed. After replacing the faulty switch, etc., and confirming the repair, the switch was switched to the O-system switch network 21 again and used.

[Issues that ribs are trying to solve]

In this way, in the conventional example, a network consisting of many unit switches requires duplication, switching circuits, and switching control circuits, which is extremely costly in terms of cost and space. The situation was disadvantageous. In addition, even if an IN in the switch network fails, the entire switch network is switched, so all active calls will be affected, and continuity can be maintained by switching calls that are in use in areas other than the failure location. had the disadvantage of requiring complex circuitry or software control.

SUMMARY OF THE INVENTION The present invention aims to eliminate such drawbacks and to provide a switching device in which the configuration of the switch network can be expanded spatially and the speed can be increased.

[Means to solve the problem]

The present invention has a multistage configuration in which unit switches are connected by links, and includes a switch network in an asynchronous transmission mode and a control device that controls link connections of the switch network. The switch circuit network includes a first circuit means for connecting each incoming line to a plurality of unit switches constituting the first stage, and a first circuit means for making a multi-point connection between this incoming line and a plurality of unit switches constituting the first stage for each incoming line, and and a second circuit means for multi-point connecting a plurality of unit switches constituting the unit switch, the link has a transmission rate higher than the incoming and outgoing transmission rates, and the control device connects the unit switch in a faulty state. The device is characterized by having means for allowing a call that is blocked and passed through this unit switch to pass to another unit switch belonging to the stage to which this unit switch belongs.

Here, the transmission speed of the link may be twice the transmission speed of the incoming and outgoing lines.

[Effect]

On the input side, one incoming line is multi-connected to multiple unit switches, and on the output side, multiple unit switches are multi-connected to one outgoing line, and the link speed between each switch stage is set higher than that of the outgoing line to prevent failures. When a fault occurs, only the faulty unit switch is blocked, and cells passing through the faulty switch are diverted to other links.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 is a block diagram showing this embodiment.

That is, this embodiment has a multi-stage configuration in which unit switches are connected by links, as shown in FIGS. Control device 1 that controls the connection
5, and further, as a feature of the present invention,
The switch network 10 has incoming lines 1.2, . 8, unit switches 100 and 101 (110 and 111, -11) constituting the first stage with this input line 1 (2,,8)
80 and 181), and the outgoing lines 1.2, . This output line 1 every 8 (2,
-18> and unit switches 300 and 301 (310 and 311, -1380 and 381
) and a second circuit means for making a multi-point connection between the
The link has a transmission rate higher than the transmission rate of the incoming line and the outgoing line, and the control device 15 blocks the unit switch in the failure state and transfers calls passing through this unit switch to other units belonging to the stage to which this unit switch belongs. It has a means to pass through the switch.

Next, the operation of this embodiment will be explained.

Figure 2 shows an example when the switch network configuration is normal (no failure), and Figure 3 shows an example when a failure occurs in a unit switch and a call cell using the failed switch bypasses other links. Indicates the state in which Under normal conditions, cells of calls coming in from the incoming line are sent to the first stage unit switches 100 to 181 and the second stage unit switches 100 to 181 according to preset path information.
It goes out to the target outgoing line through either of the unit switches 200 to 281 in the tier and the unit switches 300 to 381 in the third tier. In Figure 1, in a three-stage switch configuration, the cell that comes in from input line 1 is the unit switch 100.20.
0 and 300 and exits to exit line 1. FIG. 3 shows a case where unit switch 200 is at fault; in this case, unit switches 100, 200 and 300
Cells that were passing through unit switches 100, 201 and 300 will be routed to pass through unit switches 100, 201 and 300.

In addition, for switching when the first stage unit switch that accommodates the incoming line and the last stage unit switch that accommodates the outgoing line become faulty, the incoming line and the outgoing line can be multi-connected to multiple unit switches (
spatial expansion). This image is shown in FIG. 3(a). Furthermore, if cells passing through the faulty unit switch are diverted to another switch, the traffic of the other switches will be put under pressure, but this can be dealt with by increasing the link speed of the switch above the line speed. Speed up-
An image of this is shown in Figure 3(b). This example shows a case where the link speed is twice the line speed.

〔Effect of the invention〕

As explained above, the present invention has the effect of being able to obtain an economical redundant configuration compared to a system in which the same switch network is set up redundantly and a switching circuit, a switching control circuit, etc. are also installed. Furthermore, only the cells of calls passing through the failure unit switch are affected by instantaneous interruptions due to detour switching, while the cells of many calls passing through other switches are not affected at all. In addition, switching the switch can be done in the same procedure as the route setting when setting up a normal call.
This has the advantage of being able to utilize control circuits and software for call setup. Furthermore, since the link speed is set higher than the line speed, the cell discard characteristics and the like are improved during normal operation, which has the effect of providing high-quality communication.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. FIG. 2 is a diagram showing the normal state of the embodiment of the present invention. FIG. 3 is a diagram showing the state of the embodiment of the present invention when a failure occurs. FIG. 4 is a diagram showing a spatially expanded configuration and an expanded image of link speed. FIG. 5 is a block diagram showing the configuration of a conventional example. 3... Switching circuit, 4... Switching control circuit, 10...
Switch circuit network, 15...control device, 20...0 system switch network, 21...1 system switch network, 100.101.110.111 to 180.1
81.200, 201-28o. 281.300.301 to 380.381...unit switch.

Claims (1)

[Claims] 1. In a switching device that has a multi-stage configuration in which unit switches are connected by links, and includes a switch network in an asynchronous transmission mode and a control device that controls link connections of this switch network. , the switch circuit network includes a first circuit means for making a multi-point connection between the incoming line and a plurality of unit switches constituting the first stage for each incoming line, and a first circuit means for making a multi-point connection between this incoming line and a plurality of unit switches forming the first stage, and a first circuit means for making a multi-point connection between this incoming line and a plurality of unit switches forming the first stage, and a final stage with this outgoing line for each outgoing line. a second circuit means for multi-point connection with a plurality of unit switches, the link is composed of a device having a transmission rate higher than the transmission rate of the incoming and outgoing lines, and the control device connects the unit switch in a faulty state. A switching device characterized by having means for blocking a call passing through this unit switch and allowing it to pass through to another unit switch belonging to the stage to which this unit switch belongs. 2. The switching device according to claim 1, wherein the transmission speed of the link is twice the transmission speed of the incoming line and the outgoing line.