Switching complex architecture and operation

A system operable to communicate a plurality of signals having various signal formats including time-division multiplexed signals and signals carrying asynchronous transfer mode cells, the system comprising:

• an interface card operable to receive a plurality of incoming signals, to format the incoming signals into transport signals, to route the transport signals to at least one of a plurality of switching fabrics, to receive switched transport signals from at least one of the switching fabrics, and to facilitate transmission of the switched transport signals;
• a primary rate switching fabric operable to receive a first plurality of transport signals and to switch the first plurality of transport signals at a first level;
• a sub-rate switching fabric operable to receive a second plurality of transport signals carrying time-division multiplexed information and to switch the second plurality of transport signals at second level that is a more granular level than the first level;
• and
• an asynchronous transfer mode switching fabric operable to receive a third plurality of transport signals carrying asynchronous transfer mode cells, and to switch asynchronous transfer mode cells among the third plurality of transport signals carrying asynchronous transfer mode cells.

An interface card operable to interface a communication system having a switching complex operable to receive and process a plurality of transport signals carrying time-division multiplexed information and a plurality of transport signals carrying asynchronous transfer mode cells, wherein the switching complex comprises:

• a primary rate switching fabric operable to receive a first plurality of transport signals and to switch the first plurality of transport signals at a first level;
• a sub-rate switching fabric operable to receive a second plurality of transport signals carrying time-division multiplexed information and to switch the second plurality of transport signals at second level that is a more granular level than the first level;
• and
• an asynchronous transfer mode switching fabric operable to receive a third plurality of transport signals carrying asynchronous transfer mode cells, and to switch asynchronous transfer mode cells among the third plurality of transport signals carrying asynchronous transfer mode cells.

A method of communicating time-division multiplexed information and asynchronous transfer mode cells using a single switching complex, the method comprising:

• receiving at the switching complex a plurality of transport signals comprising:
• a first transport signal comprising pass-through traffic requiring primary rate switching;
• a second transport signal comprising sub-rate traffic requiring sub-rate switching;
• and
• a third transport signal comprising asynchronous transfer mode cells requiring asynchronous transfer mode cell switching;
• communicating each transport signal to a switching fabric operable to perform a switching function associated with that signal;
• performing primary rate switching on the first transport signal;
• performing sub-rate switching on the second transport signal;
• and
• performing asynchronous transfer mode cell switching on the third transport signal.