Re: [TERNLI] Forwarding corrupt packets

"alessandro salvatori" <sandr8@gmail.com> Fri, 01 September 2006 16:27 UTC

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Date: Fri, 1 Sep 2006 14:39:16 +0000
From: "alessandro salvatori" <sandr8@gmail.com>
To: "Michael Welzl" <michael.welzl@uibk.ac.at>
Subject: Re: [TERNLI] Forwarding corrupt packets
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On 01 Sep 2006 16:30:36 +0200, Michael Welzl <michael.welzl@uibk.ac.at>; wrote:
> > In both cases, the destination address is not trusted anymore, so you're
> > potentially sending the corrupt packet to the wrong _place_. If you
> > can't send it the right place, then why are you sending it?
>
> i remember you saying some time ago that sending it to the
> wrong destination isn't a big problem for the network, and
> therefore the lack of a checksum in ipv6 isn't a big issue.
>
> chances are that it would reach the right place, so where's
> the problem?

Well, let me be the devil's lawyer... Can you trust the TTL field to
be monotonically decreased if frames get corrupted? You can not, and
packets would be able to be forwarded forever. Well, they wouldn't if
they eventually reached their destination, but remember the fact that
you might forward packets with a varying destination address, and you
wouldn't even need to have route loops to keep trying to route to a
"moving" target...

-- 
Alessandro Salvatori