Hi Remi, > -----Original Message----- > From: Rémi Després [mailto:[email protected]] > Sent: Friday, May 07, 2010 9:20 AM > To: Templin, Fred L > Cc: Mark Townsley; softwires > Subject: Re: [Softwires] I-D Action:draft-ietf-softwire-ipv6-6rd-09.txt > > Hi Fred, > > > Le 6 mai 2010 à 16:52, Templin, Fred L a écrit : > > > Not sure whether any changes are necessary, > > AKAIKT, ll changes that were agreed in Anaheim are now in the document, so > that it can proceed. > > > but in terms > > of MTU the tunnel should try for more than 1280 if possible. > > Right.
You tend to cut out important parts of messages. The high order consideration is the following: + Otherwise, it may be difficult to configure other tunnels + (VPNs, etc.) over the 6rd tunnel. This point is in fact the sole reason for my post. Any device within a 6rd site that would like to configure a VPN or other tunnel that connects to a device outside the site is dependent on the 6rd router setting a sufficiently large MTU on its tunnel interface. > And this is in fact implied by the current text: > > "the 6rd Tunnel MTU should be set to the known IPv4 > MTU minus the size of the encapsulating IPv4 header (20 bytes)" No problem there. > Since ISPs know in general that they support IPv4 MTUs well beyond 1300, they > should tunnel MTUs to > well beyond 1280. > > It is only "Absent of more specific information" that "the 6rd Tunnel MTU > SHOULD default to 1280 > bytes." If 6rd router implementations take the overly conservative route suggested above and turn the configuration knob all the way down to 1280, devices inside the site that wish to configure tunnels that leave the site will see a path MTU that would result in either failure to configure the tunnel or the need for inner IP fragmentation - both undesirable results. Fred [email protected] > Regards, > RD > > > > > Otherwise, it may be difficult to configure other tunnels > > (VPNs, etc.) over the 6rd tunnel. > > > > Thanks - Fred > > [email protected] > > > >> -----Original Message----- > >> From: [email protected] [mailto:[email protected]] On > >> Behalf Of Mark Townsley > >> Sent: Thursday, May 06, 2010 1:39 AM > >> To: softwires > >> Subject: Re: [Softwires] I-D Action:draft-ietf-softwire-ipv6-6rd-09.txt > >> > >> > >> FYI: This was an idnits-related update prior to passage to the IESG. > >> > >> - Mark > >> > >> On 5/6/10 10:30 AM, [email protected] wrote: > >>> A New Internet-Draft is available from the on-line Internet-Drafts > >>> directories. > >>> This draft is a work item of the Softwires Working Group of the IETF. > >>> > >>> > >>> Title : IPv6 via IPv4 Service Provider Networks "6rd" > >>> Author(s) : M. Townsley, O. Troan > >>> Filename : draft-ietf-softwire-ipv6-6rd-09.txt > >>> Pages : 19 > >>> Date : 2010-05-06 > >>> > >>> This document specifies an automatic tunneling mechanism tailored to > >>> advance deployment of IPv6 to end users via a Service Provider's IPv4 > >>> network infrastructure. Key aspects include automatic IPv6 prefix > >>> delegation to sites, stateless operation, simple provisioning, and > >>> service which is equivalent to native IPv6 at the sites which are > >>> served by the mechanism. > >>> > >>> A URL for this Internet-Draft is: > >>> http://www.ietf.org/internet-drafts/draft-ietf-softwire-ipv6-6rd-09.txt > >>> > >>> Internet-Drafts are also available by anonymous FTP at: > >>> ftp://ftp.ietf.org/internet-drafts/ > >>> > >>> Below is the data which will enable a MIME compliant mail reader > >>> implementation to automatically retrieve the ASCII version of the > >>> Internet-Draft. > >>> > >>> > >>> > >>> _______________________________________________ > >>> Softwires mailing list > >>> [email protected] > >>> https://www.ietf.org/mailman/listinfo/softwires > >> > >> _______________________________________________ > >> Softwires mailing list > >> [email protected] > >> https://www.ietf.org/mailman/listinfo/softwires > > _______________________________________________ > > Softwires mailing list > > [email protected] > > https://www.ietf.org/mailman/listinfo/softwires _______________________________________________ Softwires mailing list [email protected] https://www.ietf.org/mailman/listinfo/softwires
