the scheme that josh karlin has been advocating in pretty good bgp
involved only supressing a doubtful announcement when you have a
better, more trusted announcement.
Not a doubtful announcement, a novel announcement. Not a better
announcement, a more usual announcement. The trust part, like beauty,
is in the eye of the beholder.
Don't get me wrong - I think basing decision on some "trusted"
summary of historical behavior is going to be important, unless and
until we get some approach that gives a more deterministic answer.
But I do believe that we need to consider carefully how this will
play with dynamic, particularly unplanned, changes in who is announcing what.
If there turn out to be cases where dynamic, particularly unplanned,
changes get rejected by this technique in favor of stale data,
then there should be consideration given to how to amend the scheme
to prevent that or suggest operational practices to get around it.
--Sandy
sandy,
>the scheme that josh karlin has been advocating in pretty good bgp
>involved only supressing a doubtful announcement when you have a
>better, more trusted announcement.
Not a doubtful announcement, a novel announcement. Not a better
announcement, a more usual announcement. The trust part, like beauty,
is in the eye of the beholder.
i just don't think you're following along. i think we're talking
about different things. read josh, stephanie forrest and jennifer
rexford's paper:
http://www.cs.unm.edu/~treport/tr/05-10/pgbgp.pdf
Don't get me wrong - I think basing decision on some "trusted"
summary of historical behavior is going to be important, unless and
until we get some approach that gives a more deterministic answer.
But I do believe that we need to consider carefully how this will
play with dynamic, particularly unplanned, changes in who is
announcing what.
josh's scheme only comes into play when there are two, competing
origination patterns. in this case the question is just which one to
believe.
agreed that we should be careful with anything that reduces the
ability of people to change routing dynamically. but let's remember:
that ability is already constrained by the fact that responsible
providers use prefix filters and require some kind of out-of-band
(IRR, letter, email) validation of prefix ownership. routing a new
prefix with a new origination pattern is not especially dynamic now,
so let's not worry about throwing out a baby that's not even in the
bath.
t.