On Tue, Jan 23, 2024 at 03:37:25PM -0800, William Herrin wrote:
> Nevertheless, in the protocol's design, the one expressed in the
> RFC's, AS path length = distance.

        Bill,

        The protocol was also developed at a time when everyone
utilized the same transit provider, and all other ASes were 
regional or local in scope.

        Still, I'm not sure your assertion is true.  There are
senior network engineers on this list who weren't even alive 
when 1105 was published, and express contemplation of AS path
as a tiebreaker doesn't come into it until 1164:

        "1. An AS can minimize the number of transit ASs.  
        (Shorter AS paths can be preferred over longer ones.)"

        Note the can...hardly a MUST, or a SHOULD.  AS hop
count was never intended as a large hammer, and it has never
been one in practice, since most people are making their
decisions based on local preference, which for the last couple
of decades is typically set based on internal community tagging.

        --msa

Reply via email to