Stability of CIOQ switches with finite buffers and non-negligible round-trip time

We propose a systematic method to determine the lower bound for internal buffering of practical CIOQ (combined input-output queued) switching systems. We introduce a deterministic traffic scenario that stresses the global stability of finite output queues. We demonstrate its usefulness by dimensioning the buffer capacity of the CIOQ under such traffic patterns. Compliance with this property maximizes the performance achievable with finite buffers.