JPH0336845A - Self-routing switching network - Google Patents

Abstract

PURPOSE:To increase the scale of a switch by connecting two unit switches adjacent to each other and adding an output link number provided with a mark of an identification code to transfer information generated from an input link with the absence of input information. CONSTITUTION:A switching network is constituted by connecting inputs and outputs between adjacent 2X2 unit switches 104. The switch 104 outputs an output with a smaller output link number to a lower link and an output with a larger output link number to an upper link when two inputted output link numbers are both output link numbers without any mark. When one of the two inputs is a marked output and the other is an unmarked output and both the output link numbers are not equal, the outputs are sent in the order of quantity similarly as above, and in the case of the marked output link number, the marked output link number is decremented by one when it is transferred from the upper link to the lower link and the marked output link number is incremented by one when it is transferred from the lower link to the upper link.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention is utilized in a self-routing switch network used in nodes of a high-speed packet communication system. The present invention provides a virtual identification code for switch control as an output link number for an input link without transfer information in a self-routing switch network composed of a wire-like sorting circuit network that quickly switches fixed-length block transfer information. The present invention relates to a switch configuration method that unifies unit switches, shortens wiring length, and facilitates LSI integration by assigning output link numbers and configuring a net-like switch network of unit switches with two inputs and two outputs.

[Conventional technology]

Conventionally, the Hanocha Banyan (Batch
A configuration method called er-Banyan) network is known.

References: Alan Huang, 5cott Kn
auer “5TARITεA WIDEBAND D
IGTAL 5WITCH", Proceeding
s of Global Telecommunicat
ion conference in 1934゜pp,
121-1251984゜The self-routing switch network shown in FIG. This is a switch network based on unit switches (called unit switches).

The first half of this switch network, indicated by reference numeral 402, is a batcher network that sorts fixed-length block transfer information to which a header of an output link number inputted to an input link 401 is attached, and the second half, indicated by reference numeral 403. This is a Hanyang network that outputs to a desired output link of the output link 406.

The unit switches 404 of the Vanochar network rearrange the output link numbers in ascending order in the direction of the arrows and output them.

Next, the operation of this switch network will be explained.

A fixed-length block transfer information cell having an output link number as a header is input to the input link 401 . This output link number is shown here in decimal notation. Note that, since no transfer information is input to the third and eighth input links, an output link number of "X" indicating that there is no transfer information to be sent is input. In the batcher network 402, this "X" exceeds the output link number, for example, X=8. Note that "X" is ignored in Banyan class.

The input transfer information, each assigned an output link number, is sorted by the batcher network 402 in descending order of the output link number, and the output of the batcher network 402 is sorted from the bottom in order of "0. 1. 2. 4. 5. 6X, X” and input to the Hanyang network 403.

In the first stage of the Banyan network 403, a modular 8 calculation is performed on the output link number, and if Y=0 to 3,
Routed to the link below the unit switch 404, Y
=4 to 7, it is routed to the link above the unit switch 404. In the second stage, a modular 4 operation is performed, and if Z=0.1, it is routed to the link below the unit switch 404, and if Z=2.3, it is routed to the link above the unit switch 404. In the third stage, the calculation of modinilla 2 is performed, and if it is W-0, it is output to the link below, and Wl
If so, it will be output to the link above.

In this way, output link 406 includes input link 1
Transfer information according to the output link number input in 01 is output.

In this way, the conventional Batcher-Banyaninch network performs decentralized and autonomous operations without requiring external control, and has the advantage of being able to operate at high speeds. Furthermore, it is known that when the number of human output links is limited to a power of 2, the number of 2×2 unit switches is minimized, and the Batcher network has the advantage of minimizing the circuit scale.

[Problem to be solved by the invention]

However, this conventional Batcher-Pangyang switch network has the problem that as the number of human output links increases, the wiring length between the 2 x 2 unit switches becomes longer and many overlaps occur between the wiring. It needs to be done dimensionally. In addition, there are two different kinds of 2 types of Batcher net and Banyan net.
× Requires 2 unit switches.

An increase in wiring length causes a delay due to the wiring length, which puts a limit on high-speed operation. Further, the complexity of wiring and the coexistence of different types of unit switches have disadvantages that make it difficult to implement into an LSI.

In addition, the number of human output links increases, and l-chip LSI
If the number of chips cannot be accommodated, it is necessary to configure the chips by dividing them, but in conventional batcher networks, although there is regularity in the arrangement when focusing on a certain stage, the overall structure is the same. Since the chip cannot be divided, it has the disadvantage that even if the chip is divided, multiple configurations are required.

Furthermore, since the number of human output links in the batcher network is limited to powers of 2, it is not possible to provide the minimum necessary bottom according to demand, and in the worst case, the switch accommodation efficiency is approximately 50%.
There was a drawback that it became smaller.

The present invention aims to provide a self-routing switch network that can be made into a single module by using a switch network having a structure in which unit switches of a single structure are connected in a lattice pattern, and that can be easily converted into an LSI by shortening the wiring. purpose.

[Means to solve the problem]

The present invention is a 2-input, 2-output unit configured to input transfer information to which a link number of output light is assigned, compare the output link numbers of the input transfer information, and select the output route based on the magnitude relationship. In a self-routing switch network in which switches are connected in a network, two adjacent unit switches in the front and rear stages are connected in the direction in which the signal passes through the unit switch. The transfer information generated from the link is configured to be given an output link number marked with an identification code, and when both inputs have an unmarked output link number, the output of the input When the link numbers are compared and cross-connected or non-cross-connected depending on the output link number, and one input is a marked output link number and the other input is an unmarked output link number, If the output link numbers are different, cross-connect or non-cross-connect depending on the size, add or subtract 1 to correspond to the output direction of the marked output link number, and if both output link numbers are equal, cross-connect Add or subtract 1 to the marked output link number corresponding to the output direction,
It is characterized by a non-cross-connected configuration when both inputs are marked output link numbers.

[Effect]

Transfer information in which the output link number is added to the header as the output link number is input to the input link. For links for which there is no transfer information to be sent at that time, a marked output link number is assigned to which a mark is virtually assigned as an identification code for switch control.

These input output link numbers are compared in size by each unit switch, and are cross-connected or non-cross-connected depending on the size of the output link number, and the transfer information of the larger output link number is output to one link (upper link). However, the transfer information with the smaller output link number is output to the other link (lower link).

In the switching operation with this unit switch, if there is an output link number with a mark and an output link number without a mark at the input, the magnitudes are compared and the connection is made between cross-connection or non-cross-connection depending on the magnitude of the output link number. do. In other words, when outputting a large output link number to one link (upper link), and outputting a marked output link number from the upper link input to the lower link, l is subtracted (-1) from the output link number. and output
Conversely, when outputting from a lower link input to an upper link, 1 is added (+1) to the output link number and output. Also, when the output link numbers of both are the same, it is a cross connection, and the unmarked output link number is output to the other link than the input, and the marked output link number is added by 1 (+l) or subtracted by l (-1 )do. When both marked output link numbers are input, the connection is non-cross-connected, and the upper link of the input is connected to the upper link of the output, and the lower link of the input is connected to the lower link of the output.

〔Example〕

The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a diagram showing the configuration of a self-routing switch network according to an embodiment of the present invention, and this embodiment shows an example of an 8-input, 8-output switch network with 8 input links and 8 output links.

In FIG. 1, reference numeral 101 indicates input links, each of which is assigned an input link number. From this input link 101, a cell of transfer information with a header having an output link number indicated in lO base is input. Here, (0)
The parenthesized output link number 103 indicates that the input link number is given because there is no transfer information to be sent.

Reference numeral 104 denotes a unit switch with two inputs and two outputs, and in the switch network of this embodiment, the switch network is constructed by regularly arranging them in a tile shape and connecting the inputs and outputs between adjacent 2×2 unit switches. . The arrangement of the unit switches 104 is determined by the number of human output links in the switch network. As in this example, the number of input/output links is 8.
In this case, one set consists of 4 unit switches in the first row and 3 in the second row connected from the input link side, 6 sets are connected in cascade, and finally 4 unit switches are connected to the output link side. This is a configuration in which unit switches are arranged.

Reference numeral 105 indicates an intermediate output point provided for explaining the operation of the switch network, and reference numeral 106 indicates information including the output link number arriving at the output link. Reference numeral 107 denotes output links, each of which is assigned an output link number.

Here, the feature of the present invention is that the 2x2 unit switches are arranged regularly in a so-called tile shape, and the mutual wiring is limited to between adjacent 2x2 unit switches, and the output link used for the self-routing switch. Output link numbers that correspond to actual output links with forwarding information, and marked output links that do not have forwarding information and do not correspond to actual output link numbers, but are virtually assigned for switch control. By defining two types of numbers and numbers, the types of 2×2 unit switches are unified.

Next, the operation of the embodiment of the present invention will be explained with reference to FIG.

The input link 101 of this switch network has a reference numeral 102.
Transfer information in the output link number header as shown in is input. However, since no transfer information is input to the first "0" input link, it is given an output link number marked (0).

Here, the unit switch 104 operates as follows.

■ If the output link numbers of two inputs are both unmarked, output the output with the smaller output link number to the lower link, and output the output with the larger output link to the upper link.

■ If one of the two inputs is marked and the other is not, and the output link numbers of both are not equal, they are sent in order of magnitude as in ■, and
For items with marked output link numbers, when the link is transferred from the link above the input to the link below the output, the marked output link number is subtracted by 1 and output, and the link from the link below the input is transferred to the link above the output. When transferred to , the marked output link number is incremented by l and output.

If the numbers of the two inputs are equal, send what arrives at the link above the input to the link below the output, and send what arrives at the link below the input to the link above the output. . At this time, for marked output link numbers, when the link above the input is transferred to the link below the output, the marked output link number is subtracted by 1 and output, and the output is transferred from the link below the input to the link below the output. When transferred to the link above, add 1 to the marked output link number and output.

■ If two inputs both have marked output link numbers, they are not cross-connected, the link above the input is connected to the link above the output, and the link below the input is connected to the link below the output. connected and its marked output link number does not change.

In FIG. 1, the output route of the transfer information of the output link number in the opposite order to the input link number is sequentially switched by the unit switch, and the sorting is completed at the intermediate output point 105, and "0°1 , (2), 2, 3,
They are arranged in the order of 4, 5, and 6J. Then, as shown at 106, the output link of the desired output link number is reached. Also, the marked output link number with the output link number (0) at the time of the input link is the unit switch 1.
When the route is switched by 04, the output link number is incremented by 1, and at the time of output link 107, the eighth output link number <7) is attached and output.

Here, the first half from the intermediate output point 105 operates as a sorting network corresponding to a conventional Hasochar network, and the second half from the intermediate output point 105 corresponds to a conventional Banyan network.

In addition, in order to distinguish between marked output link numbers and unmarked output link numbers in the switch network of FIG.
One bit for mark identification is added as an overhand to the number of bits required to display the output link number.

The operation of the 2×2 unit switch 104 described above is shown in the following table for each case.

Next, Figures 2 and 3 show generalized examples of the above switch network.
As shown in the figure.

FIG. 2 shows the configuration of a switch network when the number N of human output links is an even number. In this case, the switch network is 1
N/2 unit switch groups A in a row A (!:B) with N/2-1 unit switch groups B arranged in a row, and the last output side is a set of N/2 A , these unit switch groups are connected in cascade in 2N-3 columns (that is, odd-numbered columns).

FIG. 3 shows the mtt of the switch network when the number N of human output links is an odd number. In this case, the switch network consists of (N-1)/2 unit switch groups A, (N-
1)/A set of AB in which two unit switch groups B are arranged is arranged, and the unit switch groups are arranged in 2N-2 rows (i.e., even numbered rows).
Constructed in cascade.

〔Effect of the invention〕

By adopting the above configuration, the switch network of the present invention has the following features.

■ Can be constructed from a single 2x2 unit sinch.

■ All 2×2 unit switches can autonomously and decentrally perform routing processing by looking only at the header of the transfer information input to the daily unit switch.

(2) Since all 2×2 unit switches are connected only to adjacent 2×2 unit switches, if the unit switches are arranged as in the embodiment, the wiring lengths are all the same and very short. Furthermore, since the wiring does not cross each other, it can be constructed on a two-dimensional plane.

■ Unit switches are arranged in tiles, so it can be divided into switch blocks with the same configuration.

For this reason, the self-routing switch of the present invention has:
Easy to integrate into LSI, ■ Suitable for high-speed operation, ■ Capacity can be increased by arranging LSI chips of the same type in two dimensions, ■ Easy to mount on a board, ■ Switch circuit design, It is easy to manufacture and test; ■ It has the effect of efficiently realizing a switch of any size.

Furthermore, the self-routing switch network of the present invention operates autonomously without external control, and the switch scale can be increased while maintaining a constant operating speed, making it ideal as a large-capacity switch circuit and suitable for use in broadband service integrated digital networks. It can be used for communication route switches in exchanges and cross-connect switches in digital cross-connect devices.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention. FIGS. 2 and 3 are generalized configuration diagrams of the present invention. FIG. 4 is a conventional configuration diagram. 101.401...Input link, 104.404.4
05... Unit switch, 105... Intermediate output point, 1
07.406... Output link, 402... Batcher network, 403... Banyan network.

Claims (1)

[Scope of Claims] 1. Two inputs configured to input transfer information to which a link number of an output destination is assigned, compare the output link numbers of the input transfer information, and select the output route based on the magnitude relationship. In a self-routing switch network in which unit switches with two outputs are connected in a network, two adjacent unit switches in the front and rear stages are connected with respect to the signal passing direction of the unit switch, and the input Transfer information generated from an input link with no information is assigned an output link number marked with an identification code. , compare the output link numbers of the inputs and perform cross-connection or non-cross-connection depending on the size, and when one input is a marked output link number and the other input is an unmarked output link number, When the output link numbers are different, they are cross-connected or non-cross-connected depending on their size.
Add or subtract 1 to correspond to the output direction of the marked output link number, and if both output link numbers are equal, cross connect and add 1 to the marked output link number to correspond to the output direction. or subtraction, and when both inputs are marked output link numbers, the self-routing switch network is configured to be non-cross-connected.