CERF@A.ISI.EDU (11/13/87)
In a large scale, highly heterogeneous internet, knowing the entire topology requires that a substantial amount of information be shared among a far-flung set of components. This is not easy - nor is the data necessarily very timely when it finally arrives. Basing routing on out-of-date information seems like an invitation to congestion - or are you discounting that on the basis of something you haven't mentioned yet? Vint
YAKOV@IBM.COM.UUCP (11/17/87)
I'd like to solicit some comments on the following proposal for
IP routing:
Instead of computing routes on a hop-by-hop basis, the
first gateway which receives packet from a host will compute complete route
(like IP source routing) and all other gateways on the path
to destination will route just based on that source routing.
That assumes, that each gateway has complete topology of the network,
and that it runs some sort of SPF (Shortest Path First) Algorithm
which can generate complete path for a given destination.
This idea (of source routing instead of hop-by-hop routing)
is similar to what is used in MAC Layer IEEE 802.5 bridges.
Both positive and negative comments are welcomed.
Many thanks in advance to all who will reply.
Jacob Rekhter (YAKOV@IBM.COM)