Linda, > IGP has been used for the Multi-path computation for a long time
IGP can and does ECMP well. Moreover, injecting metric of anycast server destination plays no role in it as all paths would inherit that external to the IGP cost. Unequal cost load balancing or intelligent traffic spread has always been done at the application layer *for example MPLS* Thx a lot, R. On Wed, Jan 12, 2022 at 8:18 PM Linda Dunbar <[email protected]> wrote: > Robert, > > > > Please see inline in green: > > > > *From:* Robert Raszuk <[email protected]> > *Sent:* Wednesday, January 12, 2022 1:00 PM > *To:* Linda Dunbar <[email protected]> > *Cc:* Les Ginsberg (ginsberg) <[email protected]>; [email protected] > *Subject:* Re: [Lsr] Seeking feedback to the revised > draft-dunbar-lsr-5g-edge-compute > > > > Hi Linda, > > > > *[LES:] It is my opinion that what you propose will not achieve your goals > – in part because IGPs only influence forwarding on a per packet basis – > not a per flow/connection basis.* > > *[Linda] Most vendors do support flow based ECMP, with Shortest Path > computed by attributes advertised by IGP.* > > > > I am with Les here. ECMP has nothing to do with his point. > > > > [Linda] Les said that “IGP only influence forwarding on a per packet > basis”. I am saying that vendors supporting “forwarding per flow” with > equal cost computed by IGP implies that forwarding on modern routers are > no longer purely per packet basis. > > > > > > Draft says: > > > > *When those multiple server instances share one IP address (ANYCAST), the > transient network and load conditions can be incorporated in selecting an > optimal path among server instances for UEs.* > > > > So if we apply any new metric to indicate load of a single anycast address > how is this going to help anything ? > > > > [Linda] The “Load” or “Aggregated Site Cost” is to differentiate multiple > paths with the same routing distance. > > > > > > You would need a mechanism where the network is smart and say per src-dst > tuple or more spreads the traffic. IGP does not play that game today I am > afraid. > > [Linda] There is one SRC and multiple paths to one DST. IGP has been used > for the Multi-path computation for a long time. > > > > Thank you, Linda > > > > Thx a lot, > R. > > > > > > > > > > > > > > >
_______________________________________________ Lsr mailing list [email protected] https://www.ietf.org/mailman/listinfo/lsr
