The point I am making is that the total number of BFD sessions in the entire network is irrelevant.
While looking scary (even if divided by 2) those numbers should not be even exposed to operators or used as counterargument. What may matter is a hypothetical scale on a per smallest PE * number of bytes each session consumes in the control plane. Rest is offloaded to the data plane. Bottom line is that I prefer to see this problem be addressed in the service layer - but will defend BFD alternative based on practical view and facts. Cheers, Robert On Tue, Jan 11, 2022 at 1:34 AM Les Ginsberg (ginsberg) <[email protected]> wrote: > Robert – > > > > The numbers are network-wide – not per node. > > And no one has mentioned config as an issue in this thread – though no > doubt some operators might have concerns in that area. > > > > Les > > > > > > *From:* Robert Raszuk <[email protected]> > *Sent:* Monday, January 10, 2022 4:30 PM > *To:* Les Ginsberg (ginsberg) <[email protected]> > *Cc:* Greg Mirsky <[email protected]>; Tony Li <[email protected]>; > Christian Hopps <[email protected]>; Aijun Wang <[email protected]>; > Shraddha Hegde <[email protected]>; Hannes Gredler <[email protected]>; > lsr <[email protected]>; Peter Psenak (ppsenak) <[email protected]> > *Subject:* Re: [Lsr] BGP vs PUA/PULSE > > > > Hi Les, > > > > *[LES:] Even a modest sized N = 100 (which is certainly not a high number) > leads to 10000 BFD sessions. N= 500 => 250,000 sessions. Etc.* > > > > Are you doing N^2 ? Why ? All you need to keep in mind is number of those > sessions per PE so in worst case (N-1) - here 99 and 499. > > > > And as we already established, configuration is optional as you can use > auto config. > > > > Thx, > > R. > > > > *[LES:] Nodes which can support thousands of BFD sessions are likely > already using many BFD sessions for other purposes. In particular, fast > detection of local failures is always going to be a priority – so if a node > has thousands of neighbors – it will likely have thousands of single hop > BFD sessions. Not to mention the plethora of other OAM uses cases being > defined. And the network-wide traffic impact as these new BFD sessions are > largely multi-hop. Are you really arguing that the introduction of many > thousands of BFD sessions is something we should not be concerned about? * > > * Les* > > > > Les > >
_______________________________________________ Lsr mailing list [email protected] https://www.ietf.org/mailman/listinfo/lsr
