> IGP cost typically is determined by comparing the preference, then the weight, > then the metric, and finally the metric2 of the two resolving routes.
Are we sure we are on the same page here ? Are you describing some new yet to be defined algorithm or Dijkstra ? Thx, R. On Wed, Jan 12, 2022 at 9:36 PM Linda Dunbar <[email protected]> wrote: > Robert, > > > > IGP cost typically is determined by comparing the preference, then the > weight, then the metric, and finally the metric2 of the two resolving > routes. > > The draft is to add another site-cost metric to the IGP computation. > > Using MPLS is too heavy. > > > > Linda > > > > *From:* Robert Raszuk <[email protected]> > *Sent:* Wednesday, January 12, 2022 1:23 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 > > > > 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
