> -----Original Message----- > From: Ronald Bonica [mailto:rbon...@juniper.net] > Sent: Tuesday, October 08, 2013 5:46 PM > To: Ole Troan; Templin, Fred L > Cc: ipv6@ietf.org; i...@ietf.org > Subject: RE: Last Call: <draft-ietf-6man-oversized-header-chain-08.txt> > (Implications of Oversized IPv6 Header Chains) to Proposed Standard > > I agree with Ole.
How so? A tunnel that crosses a 1280 MTU link MUST fragment in order to satisfy the IPv6 minMTU. If it must fragment, then an MTU-length IPv6 header chain would not fit within the first fragment, and we have opened an attack vector against tunnels. This is not a matter to be agreed or disagreed with - it is a simple fact. Thanks - Fred fred.l.temp...@boeing.com > Ron > > > -----Original Message----- > > From: ipv6-boun...@ietf.org [mailto:ipv6-boun...@ietf.org] On Behalf > Of > > Ole Troan > > Sent: Tuesday, October 08, 2013 12:17 PM > > To: Templin, Fred L > > Cc: ipv6@ietf.org; i...@ietf.org; IETF-Announce > > Subject: Re: Last Call: <draft-ietf-6man-oversized-header-chain- > 08.txt> > > (Implications of Oversized IPv6 Header Chains) to Proposed Standard > > > > Fred, > > > > > Hi, I would like to make a small amendment to what I said in my > > > previous message as follows: > > > > > > 4) Section 5, change the final paragraph to: > > > > > > "As a result of the above mentioned requirements, a packet's > header > > > chain length MUST fit within the Path MTU associated with its > > > destination. Hosts MAY discover the Path MTU, using procedures > > such > > > as those defined in [RFC1981] and [RFC4821]. However, if a host > > does > > > not discover the Path MTU, it MUST assume the IPv6 minumum MTU of > > > 1280 bytes [RFC2460]. The host MUST then limit each packet's > header > > > chain length to the Path MTU minus 256 bytes in case additional > > > encapsulation headers are inserted by tunnels on the path." > > > > I would claim that additional encapsulation headers are already > > considered in the 1280 minimum MTU. > > as in: 1500 - 1280. > > > > cheers, > > Ole > -------------------------------------------------------------------- IETF IPv6 working group mailing list ipv6@ietf.org Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
