On 5/6/15 15:56, Randy Bush wrote:
a fellow researcher wants
> to make the case that in some scenarios it is very important for a
> network operator to be able to specify that traffic should *not*
> traverse a certain switch/link/group of switches/group of links
> (that's true right?). Could you give some examples? Perhaps point
> me to relevant references?
if so, why? security? congestion? other? but is it common? and, if
so, how do you do it?
My experience has been with MPLS overlays.
Availability: During maintenance windows, moving high-value traffic away
from potential outages while keeping the tunnels full of BE; manually
manipulating MPLS tunnel affinities (though this could be automated
fairly easily).
Congestion: Whenever traffic load spikes past a threshold;
diffserv-aware TE to prevent certain classes of traffic from routing
over links with limited bandwidth, handled automatically via auto-bw.
Preventing non-optimal tunnel paths. No transoceanic trombones,
please; MPLS link affinities designed into the network.
-Scott