This is one of many reasons why entropy labels were invented. Intermediate nodes should not be looking at payloads.
Yours Irrespectively, John > -----Original Message----- > From: nvo3 [mailto:[email protected]] On Behalf Of Ian Cox > Sent: Monday, May 04, 2015 7:42 PM > To: [email protected]; [email protected] > Subject: Re: [nvo3] I-D Action: draft-ietf-nvo3-vxlan-gpe-00.txt > > I'll provide a reason why providing intentional indication for next layer is > better than essentially guessing it. Using MPLS as an example. MPLS has no > indication in the label stack for intermediate nodes what the underlying > payload is. To achieve better load balancing of MPLS traffic most hardware > today looks to see if the first nibble is 4 or 6 then parse into the payload > under the belief that it is a IPv4 or v6 packet. The 4 or 6 guess for the > underlying MPLS payload being an IP packet was fine until IEEE allocated MAC > addresses starting with 6. Unintended results occur when you parse MAC > addresses as IP addresses and feed than into the ECMP calculation. > > > Ian > > -----Original Message----- > From: nvo3 [mailto:[email protected]] On Behalf Of Behcet Sarikaya > Sent: Monday, May 04, 2015 2:02 PM > To: [email protected] > Subject: Re: [nvo3] I-D Action: draft-ietf-nvo3-vxlan-gpe-00.txt > > Hi VXLAN-gpe authors, > > After reading many times and discussions with one of the 12 coauthors :) I > think I now understand better this draft. > > The source of misunderstanding was the lack of problem statement. My > suggestion is to clearly define what this draft is intended to solve. > > Due to the fact that VXLAN is mentioned so much and Section is almost > copied from RFC 7248 causes a lot of confusion. > > What I understand is that this draft is addressing is non Layer 2 data center > networks. VXLAN addresses Layer 2 data center networks and always > assumes Ethernet frames in the payload. > Virtual machines always generate Layer 2 frames. VXLAN addresses VM-to- > VM communication. > > In general not all data center networks are Layer based, i.e. some are Layer 3 > based and there are no VMs that's why VXLAN-GPE does not talk about VMs. > > I suggest that this point be clarified in the draft. > > Given the above, my suggestion is to remove Ethernet from the list of > encapsulations and leave it to VXLAN. > > Given the above, I think that next protocol field is not needed. > Version of IP is in the very first field in IP header. But maybe you can > convince me? > > If VXLAN-gpe is UDP encapsulation of IP packets than it should be discussed > in intarea list, just like GUE which is being discussed. > Already Xiaohu suggested this on intarea list. > > Regards, > > Behcet > > > On Fri, May 1, 2015 at 8:01 PM, <[email protected]> wrote: > > > > A New Internet-Draft is available from the on-line Internet-Drafts > directories. > > This draft is a work item of the Network Virtualization Overlays Working > Group of the IETF. > > > > Title : Generic Protocol Extension for VXLAN > > Authors : Paul Quinn > > Rajeev Manur > > Larry Kreeger > > Darrel Lewis > > Fabio Maino > > Michael Smith > > Puneet Agarwal > > Lucy Yong > > Xiaohu Xu > > Uri Elzur > > Pankaj Garg > > David Melman > > Filename : draft-ietf-nvo3-vxlan-gpe-00.txt > > Pages : 22 > > Date : 2015-05-01 > > > > Abstract: > > This draft describes extending Virtual eXtensible Local Area Network > > (VXLAN), via changes to the VXLAN header, with three new > > capabilities: support for multi-protocol encapsulation, operations, > > administration and management (OAM) signaling and explicit > > versioning. > > > > > > The IETF datatracker status page for this draft is: > > https://datatracker.ietf.org/doc/draft-ietf-nvo3-vxlan-gpe/ > > > > There's also a htmlized version available at: > > https://tools.ietf.org/html/draft-ietf-nvo3-vxlan-gpe-00 > > > > > > Please note that it may take a couple of minutes from the time of > > submission until the htmlized version and diff are available at > > tools.ietf.org. > > > > Internet-Drafts are also available by anonymous FTP at: > > ftp://ftp.ietf.org/internet-drafts/ > > > > _______________________________________________ > > nvo3 mailing list > > [email protected] > > https://www.ietf.org/mailman/listinfo/nvo3 > > _______________________________________________ > nvo3 mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/nvo3 > > _______________________________________________ > nvo3 mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/nvo3 _______________________________________________ nvo3 mailing list [email protected] https://www.ietf.org/mailman/listinfo/nvo3
