Xport Approaches -- Wormhole Switching
Wormhole routers send entire message in a single packet; “dynamically circuit switched”
- Eliminates overhead of set-up/tear-down
- Fully exploits pipelining, minimizes header bits
- Still monopolizes resources, penalizing short messages
- Message delivered in order
WH is the most popular transport method for interconnection networks -- simpler
Compromise schemes
- Large, e.g. page, variable length packets
- Allow small messages to “play through”