Method and apparatus for an expandable switching element

1. A module for processing signals, comprising:

first input ports of a first switch element accessible via a module front panel;

first output ports of the first switch element accessible via the module front panel;

second input ports of the first switch element accessible via connections on the module other than connections on the module front panel;

second output ports of the first switch element accessible via connection on the module other than connections on the module front panel; and

the first switch element configured to switch signals received by the first input ports and the second input ports to the first output ports and the second output ports;

the module further comprising at least one second switch element forming a pair with the first switch element, the pair formed without modifying one or more connections to at least one of the first input ports and the first output ports of the first switch element, the module providing an aggregate switching capacity for a combination of the first switch element and the at least one second switch element, the aggregate switching capacity being increased at least with respect to a number of ports of one or more of the first switch element and the at least one second switch element as compared with a switching capacity of one of the first switch element and the at least one second switch element, the first switch element and the at least one second switch element enabled to be paired, via connection between the second input ports of the first switch element and the second output ports of the at least one second switch element, and via connection between the second output ports of the first switch element and the second input ports of the at least one second switch element.

2. The module according to claim 1 , wherein a number of the first input ports of the one or more of the first switch element and the at least one second switch element is the same as a number of the second output ports of the one or more of the first switch element and the at least one second switch element.

3. The module according to claim 1 , wherein a number of the first input ports of the one or more of the first switch element and the at least one second switch element is fewer than a number of second output ports of the one or more of the first switch element and the at least one second switch element.

4. The module according to claim 1 , wherein the first switch element comprises suitable circuitry to switch a number of inputs that is twice a number of the first input ports of the first switch element.

5. The module according to claim 1 , wherein the second input ports of the one or more of the first switch element and the at least one second switch element and the second output ports of the one or more of the first switch element and the at least one second switch element are accessible via a backplane into which the module is inserted.

6. The module according to claim 1 , wherein three or more ports of the second input ports of the one or more of the first switch element and the at least one second switch element are accessible via connections on the module other than connections on the module front panel.

7. The module according to claim 1 , wherein the at least one second switch element is configured to switch signals received by the first input ports and the second input ports of the one or more of the first switch element and the at least one second switch element to the first output ports and the second output ports of the one or more of the first switch element and the at least one second switch element.

8. The module according to claim 1 , wherein the aggregate switching capacity is increased based upon the at least one second switch element providing at least one additional port to the pair as compared with at least one of the first input ports, the second input ports, the first output ports, and the second output ports of the first switch element.

9. A multi-stage switch, comprising:

first switching modules enabled to communicate with second switching modules; and

third switching modules enabled to communicate with the second switching modules,

wherein each of the second switching modules is enabled to be paired, without modifying one or more connections to at least one of first input ports and first output ports of each of the second switching modules, with another second switching module via the first input ports and the first output ports of each of the pair of the second switching modules and a given second switching module of the second switching modules is enabled to be paired with the another second switching module via connection between second output ports of the another second switching module and second input ports of the given second switching module and via connection between second output ports of the given second switching module and second input ports of the another second switching module, and, when paired, one of the pair of the second switching modules is configured to be an enhanced switching module that switches input signals received via its first input ports and its second input ports to its first output ports and its second output ports, and the other of the pair of the second switching modules is configured to be a forwarding module that communicates input signals received via its first input ports to its second output ports and communicates input signals received via its second input ports to its first output ports, the multi-stage switch providing an aggregate switching capacity that is increased at least with respect to a number of ports of one or more of the given second switching module and the another second switching module as compared with a switching capacity of one of the first switching modules, the second switching modules, and the third switching modules.

10. The multi-stage switch according to claim 9 , wherein, for each of the second switching modules, a number of the second input ports is the same as a number of the first output ports.

11. The multi-stage switch according to claim 9 , wherein for each of the second switching modules, a number of the second input ports is less than a number of the first output ports.

12. The multi-stage switch according to claim 9 , wherein each of the second switching modules are inserted into a backplane and each of the second switching modules are paired by coupling, to allow communication via the backplane.

13. The multi-stage switch according to claim 9 , wherein, prior to pairing, each of the second switching module switches signals received via its second input ports to its second output ports.

14. The multi-stage switch according to claim 9 , wherein the given second switching module is further enabled to be paired with the another second switching module following installation of the given second switching module.

15. A method for configuring switching modules, comprising:

coupling second output ports of a first switching module with second input ports of a second switching module to allow communication from the first switching module to the second switching module;

coupling second output ports of the second switching module with second input ports of the first switching module to allow communication from the second switching module to the first switching module;

configuring one of the first switching module and the second switching module as a forwarding module;

configuring other of the first switching module and the second switching module as an enhanced switching module;

providing an aggregate switching capacity in the enhanced switching module that is increased at least with respect to a number of ports of one or more of the first switching module and the second switching module as compared with a switching capacity of one of the first switching module and the second switching module, the increased aggregate switching capacity being provided without modifying one or more connections to at least one of first input ports and first output ports of the first switching module; and

wherein the enhanced switching module switches signals from its first input ports and its second input ports to its first output ports and its second output ports, and the forwarding module communicates signals from its second input ports to its first output ports and communicates signals from its first input ports to its second output ports.

16. The method according to claim 15 , wherein, prior to being coupled with the second switching module, the first switching module is configured to switch first input signals from its second input ports to its second output ports as first output signals.

17. The method according to claim 16 , wherein the forwarding module is configured to receive second input signals via its second input ports and transmit second output signals via its second output ports.

18. The method according to claim 17 , wherein the enhanced switching module switches the first input signals and third input signals, wherein the third input signals are communicated to the first input ports of the enhanced switching module via the first output ports of the forwarding module.

19. The method according to claim 18 , wherein the enhanced switching module outputs the switched signals to its first output ports and to its second output ports.

20. The method according to claim 18 , wherein the forwarding module outputs the switched signals to its first output ports and to its second output ports.

21. The method according to claim 17 , wherein the forwarding module switches the second input signals and fourth input signals, wherein the fourth input signals are communicated to the first input ports of the forwarding module via the first output ports of the enhanced switching module.

22. A method for configuring a switch, comprising:

pairing, in a stage of a multi-stage switch, a first switching module with a second switching module by coupling second output ports of the first switching module with second input ports of the second switching module to allow communication of first output signals to the second switching module, and coupling second output ports of the second switching module with second input ports of the first switching module to allow communication of second output signals to the first switching module;

configuring one of the first switching module and the second switching module as a forwarding module;

configuring other of the first switching module and the second switching module as an enhanced switching module;

providing an aggregate switching capacity in the enhanced switching module that is increased at least with respect to a number of ports of one or more of the first switching module and the second switching module as compared with a switching capacity of one of the first switching module and the second switching module, the increased aggregate switching capacity being provided without modifying one or more connections to first input ports and first output ports of the first switching module; and

wherein the enhanced switching module switches signals from its first input ports and its second input ports to its first output ports and its second output ports, and the forwarding module communicates signals from its second input ports to its first output ports and communicates signals from its first input ports to its second output ports.

23. The method according to claim 22 , wherein, prior to being coupled with the second switching module, the first switching module receives first input signals via its second input ports from at least one of an initial number of first stage communication modules, the first switching module is configured to switch the first input signals to its second output ports as third output signals, and the third output signals are communicated to at least one of an initial number of second stage communication modules.

24. The method according to claim 23 , comprising communicating additional signals from the first stage communication modules to the second input ports of the second switching module.

25. The method according to claim 24 , comprising providing the additional signals by increasing the initial number of the first stage communication modules.

26. The method according to claim 23 , comprising communicating additional signals from the second output ports of the second switching module to the second stage communication modules.

27. The method according to claim 26 , wherein the additional signals are communicated to additional second stage communication modules added to increase the initial number of the second stage communication modules.

28. The method according to claim 11 , further comprising pairing the first switching module with the second switching module following installation of the first switching module.