On 8/18/23 09:38, Robert Raszuk wrote:
Jakob,
With AS-PATH prepend you have no control on the choice of which ASN
should do what action on your advertisements.
My comprehension of DPA would have been more directed than the "spray &
pray" approach AS_PATH prepending provides.
However, the practice of publishing communities by (some) ASNs along
with their remote actions could be treated as an alternative to the
DPA attribute. It could result in remote PREPEND action too.
If only those communities would not be deleted by some transit
networks ....
Even then, communities have best efficacy at the closest interconnect
with the network that is using them. Since community values are
generally not coordinated Internet-wide, it would take a laborious
effort to construct the right set of communities to achieve the desired
outcome for an end-to-end source or destination path, assuming those
communities were not mangled in flight.
Mark.
