Hi Hannes, Many thanks for the slides: quite interesting and to the point. Very useful.
More inline. > From: rtgwg [mailto:[email protected]] On Behalf Of Hannes Gredler > > hi RTGWG, > > some old presentation from Dave Katz on backoff and timing. > https://www.nanog.org/meetings/nanog25/presentations/katz.ppt > [courtesy Chris Bowers for digging it up ...] > > slide 15 is of particular interest - says that if an implementation and the > system around it is properly designed then no backoff should be required. - so why did this particular implementation included a SPF backoff algorithm? ;-) - I will not comment about "properly designed" but (probably) all systems have bugs and/or sub-optimal design parts - Sorry, but I would argue that if existing SPF backoff algorithm were "properly designed", they would be standardized to allow for inter-vendor consistency - If after 10 consecutive SPFs runs in 1 second, the IGP still haven't solved the problem, then keep doing the same thing again and again may not help, at least urgency will probably not help/be needed. Eventually the IGP SPF is part of the problem e.g. by creating system & network churn, micro-loops... IMHO, trying to calm down the IGP reaction seems a valid option to try. At least this reduces the number of micro-loops in the network. - slide 15 seems to only consider intra-system impacts (looks even intra-IGP only). From a network wide perspective, the more SPF/FIB change, the more micro-loops. Bruno > > /hannes > > _______________________________________________ > rtgwg mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/rtgwg _________________________________________________________________________________________________________________________ Ce message et ses pieces jointes peuvent contenir des informations confidentielles ou privilegiees et ne doivent donc pas etre diffuses, exploites ou copies sans autorisation. Si vous avez recu ce message par erreur, veuillez le signaler a l'expediteur et le detruire ainsi que les pieces jointes. Les messages electroniques etant susceptibles d'alteration, Orange decline toute responsabilite si ce message a ete altere, deforme ou falsifie. Merci. This message and its attachments may contain confidential or privileged information that may be protected by law; they should not be distributed, used or copied without authorisation. If you have received this email in error, please notify the sender and delete this message and its attachments. As emails may be altered, Orange is not liable for messages that have been modified, changed or falsified. Thank you. _______________________________________________ rtgwg mailing list [email protected] https://www.ietf.org/mailman/listinfo/rtgwg
