Flow-control in a switch fabric

A method, comprising:

• sending data from a module within a first stage of a switch fabric to a module within a second stage of the switch fabric;
• sending a first suspension indicator from the module within the second stage to a module within a third stage of the switch fabric;
• and
• sending a second suspension indicator from the module within the third stage to the module within the first stage in response to the first suspension indicator, the module within the first stage configured to stop sending data to the module within the second stage in response to the second suspension indicator.

A processor-readable medium storing code representing instructions to cause a processor to perform a process, the code comprising code to:

• receive data from a module within a first stage of a switch fabric;
• buffer the data in a queue within a memory;
• forward the buffered data to a module within a second stage of the switch fabric;
• and
• send a suspension indicator to the module within the second stage when an amount of data within the queue exceeds a threshold, the suspension indicator configured to stop the module within the first stage from sending data.

An apparatus, comprising:

• a module within a first stage of a switch fabric;
• a module within a second stage of the switch fabric;
• a module within a third stage of the switch fabric;
• a first unidirectional data path, the first unidirectional data path configured to facilitate data transfer from the module within the first stage to the module within the second stage;
• a second unidirectional data path, the second unidirectional data path configured to facilitate data transfer from the module within the second stage to the module within the third stage;
• and
• a bidirectional data path configured to facilitate transfer of a flow-control indicator from the module within the third stage to the module within the first stage.