On-Chip Communication Architectures

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not commonly used in NoCs. However, at least one NoC architecture, the

Nostrum [5] architecture, makes use of SAF switching (along with defl ec-

tive routing).

(ii) VCT switching: This technique reduces the router latency over SAF

switching by forwarding the fi rst fl it of a packet as soon as space for the

entire packet is available in the next router (instead of fi rst waiting for

the entire packet to be received and then ensuring that suffi cient buffer

space is available in the next router before initiating packet transfer). The

other fl its follow the fi rst fl it without any delay. However, if no space is

available in the receiving buffer ...