Comment Re:Well yeah... (Score 1) 169
Infiniband (IB) isn't source routed, though myrinet is. Myrinet has the route built into the packet header and each switch rips off it's instructions as the packet enters the switch.
IB packets are associated with a Queue Pair (QP) which is associated with 2 LIDs, one for each end of the connection. I believe that the switches key off the target machine's LID and use that for a table based lookup. I keep getting my acronyms mixed up, but IB switches do a table lookup to determin the out going port for the packet that is incoming, just like ethernet, though most (if not all) of the information is pre-programmed into the switch chips via the Session Manager (SM) eliminating the need to go and query a higher authority (like ethernet ARP).
IB packets are associated with a Queue Pair (QP) which is associated with 2 LIDs, one for each end of the connection. I believe that the switches key off the target machine's LID and use that for a table based lookup. I keep getting my acronyms mixed up, but IB switches do a table lookup to determin the out going port for the packet that is incoming, just like ethernet, though most (if not all) of the information is pre-programmed into the switch chips via the Session Manager (SM) eliminating the need to go and query a higher authority (like ethernet ARP).
