Pardon the top post.
Marco, we do these things in the real world generally because we have to, not
because we don't know any better. IX participants come in all kinds of flavors,
and some have to turn some really weird BGP knobs to ensure everything works.
I very much appreciate your position -- clean, optimal standards are a great
goal -- but real world operability is the true MUST HAVE of a standard.
David
On Jun 1, 2016, at 7:12 AM, Marco Marzetti <marco(_at_)lamehost(_dot_)it>
wrote:
On 2016-06-01 13:17, Nick Hilliard wrote:
Marco Marzetti wrote:
I agree with you that you can run a route server and insert your ASn in
the path, but i think that is a lack of common sense which brings only
contraries and no benefits.
About RFC2119: It says that "SHOULD NOT" implies a valid reason to
accept a behavior, but i can't find any.
I agree that it is not a clever thing to do. The valid reason to accept
the behaviour is that it works in practice: some IXPs have done this in
production, in many cases for years.
There is a secondary reason: some rs client bgp stacks don't support the
option to accept an AS path from the RS where the leftmost entry on the
AS path != peeras.
These are not "good" reasons in the sense that they mandate behaviour
which is suboptimal, but they are valid reasons.
Nick
Nick,
I think that we should define a standard that addresses and corrects those
non-clever behaviors rather than embrace them.
My point is: even if they work in the real world, they do because of the
workarounds that other people put in place and they bring no benefits.
Regards
--
Marco