Circuit Switching (cont).
Advantages
- Do not have to break message into packets
- No storage required at intermediate nodes
- Latency generally less than packet switching
Latency is L = P/B *D + M/B
- P is the length of the probe (P << M).
- Once circuit is establish, transmission time is determined by B, the channel bandwidth. M is the message length.
- Intel iPSC-2 (circuit switching) had 10x improvement in latenency over iPSC-1 (packet switching). iPSC-2 required only 10% more time for distance nodes than nearest neighbors