[c-nsp] Anycast services

[Alexander Gall]

On Thu, 18 May 2006 16:15:58 -0400, "Tim Durack" <tdurack at gmail.com> said:

> So everybody keeps saying. I know TCP is stateful, but for a web
> proxy, seems like it would work well enough. Might have to refresh to
> fix broken state, but users are used to that kind of behaviour on the
> Internet anyway.

We actually use anycast inside our AS for one particular web
application with fairly short lived sessions (on the order of seconds)
and no state between sessions.  This works well because our IGP is
very stable.  The time scale of link failures is days or even weeks
and many failures would probably not even change the affinity of
active sessions.  I'm pretty sure that anycast would work just fine
for a web proxy in our environment.

You have to know your network and your application to make a sensible
decision, but anycast is probably applicable to more stateful
applications than many people are prepared to believe :-)

--
Alex