Virtual output queueing

Other packets in the same physical buffer destined to different (non-congested) output ports are in separate virtual queues and can therefore still be processed.

It has been shown that VOQ can achieve 100% throughput performance with an effective scheduling algorithm.

[citation needed] This scheduling algorithm should be able to provide a high speed mapping of packets from inputs to outputs on a cycle-to-cycle basis.

The VOQ mechanism provides throughput at a much higher rate than the crossbar switches without it.

[3] VOQ scheduling is often referred to as "arbitration" (resolving the concurrent access wishes), whereas the ordering of packets ("packet scheduling") is an additional task[4] following the VOQ arbitration.