When two bursts contend for the same output
port, one will be switched to the correct output port, and the other will be switched
(deflected) to any other available output port. Therefore, both bursts are given a chance
to be switched instead of dropping one of them to resolve the contention. Because
the correct output port leads usually to the shortest path (networking context) toward
the destination, the bursts that are not switched to the correct output ports may end
up following longer paths to their destinations. This technique is referred to as ???hotpotato???
routing. A drawback of this technique is the complexity associated with the
calculation of the offset time of the deflected burst since it will travel on a different
path with different hop count. Furthermore, the end-to-end high delays experienced by
All-Opt cal Intermet: Next-Generat on Network Infrastructure
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the deflected DBs may cause the DBs to be out-of-order at the destination, or trigger
upper layers retransmission mechanisms. Additionally, deflecting data bursts because
of local congestion may instigate global congestion.
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