ICMP redirect caching

[bu...@bu-cs.bu.edu.uucp]

I agree that BSD would be better off if the networking code took a
more active (and reality based) interest in the health of its routing
tables. Like some frail monarch hidden in its chambers it has too
long listened to the half truths of its wormtongued routing daemon.

TENEX/TOPS-20 use caching of ICMP Redirect derived routes. The
"default" gateways are statically assigned. Perhaps an initial
broadcast request could be used to dynamically build a weighted list
of possible gateways when the current set is empty (or contains only
reticent redirectors).

Another valuable concept is the (sparing) use of pinging to ascertain
the health of the default and active (catched) gateways.

The file [NIC]NETINFO:INTERNET.PINGING contains information regarding
the care and feeding of your GATEWAYS file.

Phil Budne, Boston University