Re: UDP zero checksums and v4 to v6 translators

[JINMEI Tatuya / 神明達哉 <jinmei at isc.org>]

At Tue, 28 Jul 2009 10:53:54 +0200,
Francis Dupont <Francis.Dupont at fdupont.fr> wrote:

>    Out of curiosity, what's the signal back to the sender that his/her
>    packet was dropped??
> 
> => none but if you really want something an unreachable / admin forbidden
> seems not so bad.

The (or one) difficult part is that in case of IPv6 if transport-layer
checksum isn't provided the responder cannot even be sure about the
source address is valid (to which a "signal" would be sent) since IPv6
doesn't have a checksum at the IP layer.

BTW, I agree with you; I oppose to loosening the current restriction.
The lack of IP layer checksum and its implication are one reason for
that.

---
JINMEI, Tatuya
Internet Systems Consortium, Inc.