Re: Last Call: <draft-ietf-6man-oversized-header-chain-08.txt> (Implicat

Fred,

> > -----Original Message-----
> > From: Ronald Bonica [mailto:rbonica(_at_)juniper(_dot_)net]
> > Sent: Tuesday, October 08, 2013 5:46 PM
> > To: Ole Troan; Templin, Fred L
> > Cc: ipv6(_at_)ietf(_dot_)org; ietf(_at_)ietf(_dot_)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.
right, and RFC2460 has this to say about it:

   IPv6 requires that every link in the internet have an MTU of 1280
   octets or greater.  On any link that cannot convey a 1280-octet
   packet in one piece, link-specific fragmentation and reassembly must
   be provided at a layer below IPv6.

cheers,
Ole

signature.asc
Description: Message signed with OpenPGP using GPGMail