Arie Thanks for responding on the polarization question and I agree it can enhance ECMP capability and maybe even counter or reduce effects of polarization.
Thanks Gyan On Tue, May 25, 2021 at 1:26 PM Arie Vayner <[email protected]> wrote: > The flow polarization or elephant flow issues are well known industry > items and they apply to both equal and unequal cost multi-path approaches. > > The objective of this proposal is to enhance ECMP, and enable unequal cost > multi-pathing, which is very useful when a service is offered by a > multitude of endpoints, which may or may not have the same capacity. > This solution has been implemented in production, and offers a real option > for traffic load management. > > Tnx > Arie > > On Tue, May 25, 2021 at 9:48 AM Jakob Heitz (jheitz) <jheitz= > [email protected]> wrote: > >> The link bandwidth community has been implemented by Cisco and deployed by >> >> our customers for several years. >> >> Polarization of flows in multipath is a well known problem, but it hasn't >> deterred >> >> people from using it. >> >> >> >> Regards, >> >> Jakob. >> >> >> >> *From:* BESS <[email protected]> *On Behalf Of * Gyan Mishra >> *Sent:* Tuesday, May 25, 2021 12:24 AM >> *To:* Satya Mohanty (satyamoh) <[email protected]> >> *Cc:* [email protected] >> *Subject:* Re: [bess] Request discussion on Cumulative Link Bandwidth >> Draft >> >> >> >> >> >> Hi Satya >> >> >> >> I read the draft and have a few questions. >> >> >> >> IPv4 does not support per flow per packet load balancing as all packets >> belonging to the same flow must hash to the same path to prevent out of >> order packets and thus is subject to polarization of flows as high >> bandwidth flows may hash to the same path and low bandwidth flows as well >> to the same path resulting in very uneven load balancing. Do to this issue >> it does not make either iBGP or eBGP can really benefit from link bandwidth >> extended community weight based load sharing. >> >> >> >> IPV6 flow label RFC 6437 stateless locally significant 5-tuple header >> hash generated 20 byte key input to hash function results in uniform 50/50 >> load balancing over EGP or IGP ECMP paths. >> >> >> >> I think it maybe a good idea to reference the IPv4 polarization issue >> with flow based load balancing and that only with IPv6 flow label can true >> 50/50 uniform load balancing be achieved. >> >> >> >> I noticed that the normative draft referenced was adopted but has not >> progressed. >> >> >> >> https://datatracker.ietf.org/doc/draft-ietf-idr-link-bandwidth/ >> >> >> >> Has the draft been implemented by Cisco or any other vendors ? >> >> >> >> Kind Regards >> >> >> >> Gyan >> >> >> >> >> >> On Sat, May 22, 2021 at 11:38 AM Satya Mohanty (satyamoh) <satyamoh= >> [email protected]> wrote: >> >> Hi all, >> >> >> >> On behalf of all the authors, we request a discussion of the draft >> https://datatracker.ietf.org/doc/html/draft-mohanty-bess-ebgp-dmz-03 >> and subsequent WG adoption. >> >> This draft extends the usage of the DMZ link bandwidth to scenarios where >> the cumulative link bandwidth needs to be advertised to a BGP speaker. >> >> Additionally, there is provision to send the link bandwidth extended >> community to EBGP speakers via configurable knobs. Please refer to section >> 3 and 4 for the use cases. >> >> >> >> This feature has multiple-vendor implementations and has been deployed by >> several customers in their networks. >> >> >> >> Best Regards, >> >> --Satya >> >> _______________________________________________ >> BESS mailing list >> [email protected] >> https://www.ietf.org/mailman/listinfo/bess >> >> -- >> >> <http://www.verizon.com/> >> >> *Gyan Mishra* >> >> *Network Solutions Architect * >> >> *Email [email protected] <[email protected]>* >> >> *M 301 502-1347 <(301)%20502-1347>* >> >> >> _______________________________________________ >> BESS mailing list >> [email protected] >> https://www.ietf.org/mailman/listinfo/bess >> > -- <http://www.verizon.com/> *Gyan Mishra* *Network Solutions A**rchitect * *Email [email protected] <[email protected]>* *M 301 502-1347*
_______________________________________________ BESS mailing list [email protected] https://www.ietf.org/mailman/listinfo/bess
