How does FNN routing really work?
Every NIC in every PC has a unique MAC address (and potentially unique IP address) — i.e., this is not channel bonding. Given this arrangement, there are two “levels” of intelligence with which FNN message routing can be accomplished. Basic Routing is trivially implemented by forcing each machine to have its own (possibly unique) routing table. Thus, when machine “A” looks-up machine “B”, it may find that “B” has a different MAC address than what machine “C” thinks is “B”. This same principle works for IP addresses, MPI nodes, etc. For example, IP works by using the host file (/etc/hosts) and a pre-loaded ARP cache (some unix-version-dependent code here) to implement each machine’s routing table. MPI works because it is built on top of the IP machanism. All KLAT2’s initial performance numbers have been achieved using only basic routing at the IP layer or above. Advanced Routing is not trivial. The difference is simply that basic routing always uses one path between a particular pair o
