KR100211029B1 - Expanded multi-channel switching network using perfect shuffle method - Google Patents

Abstract

1. TECHNICAL FIELD OF THE INVENTION

Extended Multichannel Switching Network Using Perfect Shuffle

2. The technical problem to be solved by the invention

By applying the channel grouping technique, which is a functional characteristic of MCS, with perfect shuffle network and routing tag swapper, it is possible to expand the switch capacity up to N ² × N ² without changing N × N unit MCS.

3. Summary of Solution to Invention

Compared to the non-expanded structure, the copy network has a perfect shuffle network between the group copy network (1) corresponding to the group phase and the port copy network (2) corresponding to the port phase, and the group copy network (1) and the port copy network (2). (3) Reconfigure with a copy swapper (4) that performs a swapping function of the routing tag at the front of the port copy network (2). Similarly, the non-expanded routing network also has a perfect shuffle network (7) and a port path between the group path network (5) corresponding to the group phase, the port path network (6) and the group path network (6) corresponding to the port phase. Reconfigure the path swapper (8) to perform the swapping function of the routing tag in front of the network (6).

4. Important uses of the invention

Used in the exchange network.

Description

Extended Multichannel Switching Network Using Perfect Shuffle

The present invention relates to an extended multi-channel switching network using a perfect shuffle method, and in particular, a switch using an N × N-scaled MCS that performs multi-channel switching (MCS) by a channel grouping function. The present invention relates to an extended multichannel switching network capable of expanding capacity.

1 is a block diagram of a multicast switch having a non-expansion structure using a conventional multi-channel switching (MCS). The input processing unit 11 and the input stage in units of N ports composed of the input processing units 1 to N are illustrated in FIG. N port unit channel group converting unit comprising a copy network 12 connected to the output terminals of the input processing units 1 to N and channel group converting units 1 to N connected to the output terminal of the copy network 12, respectively. 13), an N port consisting of a routing network 14 whose inputs are connected to the outputs of the channel group converters 1 to n, and an output processor 1 to N whose inputs are respectively connected to the outputs of the routing network 14; The unit output processor 15 is provided.

2 is a structural diagram of a routing tag format of a non-extended structure using a conventional MCS.

1 and 2, the input processing units 1 to N of FIG. 1 add a routing tag of a format suitable for a copy network to a received ATM cell.

In addition, the routing tag required for the copy network 12 includes an assigned bit (ASSIGNED BIT (A)) identifying a valid or invalid cell, a FANOUT (FO) indicating the number of copies of the corresponding cell, and a multichannel switching (MCS). It consists of a broadband identifier (BROADBAND IDENTIFIER (BID)) corresponding to the cell identifier in.

The copy network 12 copies and outputs the cells received from the input processing units 1 to N by the number of FANOUTs of the routing tag.

The radiation cell output from the copy network 12 is formatted by the channel group converters 1 through N with a routing tag suitable for the routing network 14. The routing tag required for the routing network 14 includes GROUP NUMBER CODED (GNC) indicating the output port of the cell, GROUP CAPACITY (GC) indicating the size of the group to which the output port belongs, and the group to which the output port belongs. It consists of a GROUP STARTING PORT (GSP) indicating the number of the starting port.

The copy cells input from the channel group converters 1 through N are output to the final output port according to the routing tag while passing through the routing network 14. Cells output from the routing network 14 are removed from the routing tag by the output processing units 1 to N, and the address information in the ATM cell header is converted and delivered to the final destination.

MCS solves the cell order integrity problem of the conventional multichannel switching technique by a unique algorithm, and can support the channel grouping technique.

However, when a conventional multicast switch as described above is chipped with an ASIC, a relatively large number of gates is required, and it is difficult to support a large switching capacity with one chip.

Accordingly, the present invention has been made to solve the above problems, the N × N-scale multi-channel switch (MCS) performing a multi-channel switch (Channel Grouping) by the channel grouping function (Channel Grouping) Perfect Shuffle to expand the switching capacity while ensuring performance such as throughput, cell loss, and cell delay of an unexpanded structure using one N × N MCS The purpose of the present invention is to provide an extended multi-channel switching network using the scheme.

1 is a block diagram of a multicast multicast switch having an unexpanded structure using a conventional MCS.

2 is a block diagram of a routing tag format having a non-expansion structure using a conventional MCS.

3 is a diagram illustrating an embodiment of an extended multi-channel switching network using a perfect shuffle method according to the present invention.

4 is a structural diagram of a routing tag format of an extended structure using an MCS according to the present invention.

5 is a diagram illustrating a routing tag swapping process for an extended structure according to the present invention.

6 is a block diagram of a perfect shuffle network for an extension structure to which the present invention is applied.

* Explanation of symbols for main parts of the drawings

1: Group copy network 2: Port copy network

3: perfect shuffle net 4: copy swapper

5: group path network 6: port path network

7: perfect shuffle net 8: path swapper

In order to achieve the above object, the present invention provides a multi-channel switching network including a plurality of N (where N is a natural number) port unit input processing unit and a plurality of channel group conversion units. A group copy network that performs a copy function with reference to a group phase routing tag of a packet, a first perfect shuffle network that distributes packets copied by the group copy network, A copy swapper for swapping a routing tag of packets distributed by the first perfect shuffle network, a copy to be copied back into the same group according to a port phase routing tag for packets passing through the copy swapper A port copy network that performs a function and delivers it to the plurality of channel group converters, and a group phase of packets input from the plurality of channel group converters ( A group path network for performing multicast switch routing with reference to a Group Phase) routing tag; A second perfect shuffle network for distributing packets routed by the group path network, a path swapper for swapping routing tags of packets routed from the second perfect shuffle network; And a port path network for routing the packet passed through the path swapper to an output processor that is a final destination according to a port phase routing tag.

In addition, the present invention is a technology belonging to the field of ATM switching technology included in an exchange apparatus when a network is constructed by an asynchronous transfer mode (ATM), and unlike a single channel switching technique generally used, a multichannel switching technique And use MCS in particular.

As described above, the present invention provides a copy network and a routing network composed of one phase in a multicast switch (see FIG. 1) by an unexpanded structure using a single N × N MCS. Are divided into Group Phase and Port Phase (see Fig. 3), and combined with the channel group function of MCS, the N × N unit MCS (N × N scale switch of non-expansion structure) The switch capacity can be expanded to a maximum of N ² × N ² without changing a copy network set or a routing network set called an N × N unit MCS.

For example, when using a 16x16 unit MCS, the switch can be extended to a maximum of 256x256 scale by the present invention. In this case, the basic routing tag format is the same as in the non-extension structure (see FIG. 2), but in the extended structure, the routing tag must be relocated for each phase (see FIG. 4). A swapper is needed between them (see Figure 5).

In addition, a perfect shuffle network (see also FIG. 6) is placed along with the swapper for fair traffic distribution and routing between the Group Phase and the Port Phase.

In terms of performance, the throughput and cell loss of the entire switch are affected only by the group phase, which is the same as the non-expanded multicast switch, and also in terms of cell delay. On average, only one cell of delay is added due to the port phase.

In addition, by dividing the non-expansion copy network and routing network shown in FIG. 1 into a group phase and a port phase, respectively, mN × mN (where 0m N, and an integer k with km = N is necessarily present). In each phase, m sets of N × N unit MCSs are arranged, and the N output ports on each N × N unit MCS arranged in a group phase are divided into m groups to form a port phase ( Port Phase) can be switched to any set of m sets of N × N unit MCSs. Each N × N unit MCS set on a port phase performs the same N × N unit MCS switching function of an unexpanded structure.

When one cell is input from a specific input processing unit, in the case of copy network 20, a copy of the desired number of groups occurs first in the N × N unit MCS set to which the cell is input. After the cell is switched to the desired port phase through the perfect shuffle network, copies of the desired number of ports occur again for each group on the port phase. Similarly, in the routing network, the cells are first routed to the desired group within the N × N unit MCS set to which the channel group conversion unit into which the cells on the group phase are input, and the routed cells are perfect. After switching to the desired port phase through the shuffle network, it is finally routed back to the desired port within each group on the port phase. Therefore, two copies and routings occur during the group phase and the port phase, respectively.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a diagram illustrating an embodiment of an extended multi-channel switching network using a perfect shuffle method according to the present invention.

As shown in FIG. 3, in the extended multi-channel switching network of the present invention, a copy network corresponds to a group copy network 1 and a port phase corresponding to a group phase. A perfect shuffle network (3) between the port copy network (2), the group copy network (1) and the port copy network (2), and a swapping function of the routing tag at the front of the port copy network (2). A copy swapper 4 is provided.

In addition, the extended multi-channel switching network of the present invention is similar to the routing network of the non-expansion structure of FIG. 1, in which the group path network 5 corresponding to the group phase and the port phase are selected. Swapping function of routing tag in front of corresponding port path network 6, perfect shuffle network 7 located between group path network 5 and port path network 6, and port path network 6 And a path swapper 8 for carrying out.

The other input processing unit, channel group converting unit, and output processing unit are functionally the same as the non-extended structure of FIG. 1, but the contents of the look-up table to be retained follow the routing tag format of FIG.

4 is a structural diagram of a routing tag format of an extended structure using an MCS according to the present invention.

The routing tag format of the extended structure shown in FIG. 4 has the same function of each field as G-FO, G-GNC, G-GC, G-, although the function of each field is the same as that of the non-extended structure shown in FIG. GSP is used only in the group phase, and P-FO, P-GNC, P-GC, and P-GSP are used only for the photo phase.

The group copy network 1 performs a copy function of an N × N unit MCS with reference to a group phase routing tag (see FIG. 4) of a packet input from an input processing unit.

The perfect shuffle network 3 distributes the packets copied by the group copy network 1 to the port copy network 2.

Packets distributed from the perfect shuffle network 3 undergo a copy swapper 4, and the positions of the Group Phase routing tag and the Port Phase routing tag are interchanged as shown in FIG. .

Packets passing through the copy swapper 4 are again copied by the port copy network 2 in the same group according to the Port Phase routing tag.

In the port copy network 2, the copy function of the N × N unit MCS is also performed.

The group path network 5 performs an MCS routing function with reference to a group phase routing tag (see FIG. 4) of a packet input from the channel group conversion unit.

The perfect shuffle network 7 routes the packets routed by the group path network 5 to the port path network 6.

Packets routed from the perfect shuffle network 7 are routed through the path swapper 8, and the positions of the group phase routing tag and the port phase routing tag are interchanged as shown in FIG. .

5 is a diagram illustrating a routing tag swapping process for an extension structure according to the present invention.

The packet passed through the path swapper 8 is routed by the port path network 6 to the output processing unit which is the final destination according to the Port Phase routing tag. In the port path network 6, the routing function of the N × N unit MCS is also performed.

In the routing tag swapping process, the N × N unit MCS used for the group phase and the port phase of the copy network and the routing network is the same, and the N × N unit MCS is the first bit of the routing tag attached to the newly input cell. Since the routing tags used in the port phase, P-FO, P-GNC, P-GC, and P-GSP, are placed in the first bit of the routing tag before entering the port phase, You need to swap with the routing tags G-FO, G-GNC, G-GC, and G-GSP.

6 is a block diagram of a perfect shuffle network for an extension structure to which the present invention is applied.

The present invention described above is capable of various substitutions, modifications, and changes without departing from the technical spirit of the present invention for those skilled in the art to which the present invention pertains. It is not limited.

As described above, the present invention applies the channel grouping technique, which is a functional characteristic of the MCS, together with the perfect shuffle network and the routing tag swapper, so that the switch capacity can be increased up to N ² × N ² without changing the N × N unit MCS It can be expanded, so that one chip can support a large switch capacity.

Claims (1)

In an extended multi-channel switching network having a plurality of N (where N is a natural number) port unit input processing unit and a plurality of channel group conversion units, a group phase routing tag of a packet passing through the plurality of input processing units a group copy network performing a copy function by referring to a phase routing tag; A first perfect shuffle network for distributing packets copied by the group copy network; A copy swapper for swapping routing tags of packets distributed by the first perfect shuffle network; A port copy network for copying the packets passed through the copy swapper to the plurality of channel group converters by performing a copy function to be copied again in the same group according to a port phase routing tag; A group path network for performing multicast switch routing with reference to a group phase routing tag of packets input from the plurality of channel group conversion units; A second perfect shuffle network for distributing packets routed by the group path network; A path swapper for swapping a routing tag of packets routed from the second perfect shuffle network; And a port path network configured to route the packet passed through the path swapper to an output processing unit which is the final destination according to a port phase routing tag.