Reliability mechanism for control protocols in arbitrated crossbar switches
Original Publication Date: 2004-Jun-03
Included in the Prior Art Database: 2004-Jun-03
We propose a reliability method to protect an imperfect (i.e., having an error rate greater than zero) control path of packet switches with input queues and a remote centralized arbitration unit (arbiter) to ensure that that the input queue state maintained by the arbiter is consistent with the actual input queue state, taking into account the round-trip time. This method has the following key advantages: - The method determines whether the queue state maintained by the arbiter is consistent with the actual queue states at the line cards. - The method also determines the magnitude of any inconsistency, thereby allowing immediate corrective action to be taken, if required. - The method can cope with control paths of arbitrary length and round-trip time, thus supporting systems of arbitrary physical size. - The method does not interfere with regular data traffic, i.e., while a check is in progress, data traffic can simultaneously proceed at full bandwidth. The method checks consistency periodically or in response to the detection of a physical error. - The method entails minimal overhead.