Re: MTU path discovery and IPSec

On Thu, 04 Dec 2003 18:03:38 EST, Barney Wolff said:

That's not how PMTUD works. If DF is set, you discard the packet and report back with ICMP. If DF is not set, you frag the packet - but that's not PMTUD, because no report ever goes back to the sender.

Oh, so we compute ONE number if DF is set, saying what number we think they should use - but if DF *isn't* set, we use a different number. Sounds like more complicated code that's just there so it can sink its teeth into the rump of the first banana-eating NOC dweller that has to figure out what's wrong.... Unless of course there's a *reason* we want it different? Though it escapes me what it might be....