Re: NIST and SP800-119

[Joe Abley <jabley () hopcount ca>]

On 2011-02-14, at 21:41, William Herrin wrote:

> On Mon, Feb 14, 2011 at 7:24 PM, TR Shaw <tshaw () oitc com> wrote:
> > Just wondering what this community thinks of NIST in
> > general and their SP800-119 (
> > http://csrc.nist.gov/publications/nistpubs/800-119/sp800-119.pdf )
> > writeup about IPv6 in particular.
>
> Well, according to this document IPv4 path MTU discovery is,
> "optional, not widely used."

Optional seems right. Have there been any recent studies on how widely pMTUd is actually used in v4?

More contentious is that Path MTU discovery is "strongly recommended" in IPv6. Surely it's mandatory whenever you're 
exchanging datagrams larger than 1280 octets? Otherwise the sender can't fragment.


Joe