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Re: transmech MTU comments
Erik,
I appreciate the humor, but this is a critical design point that needs
to be resolved:
Should we have as a goal the ability to support L2 bridges, switches,
hubs, etc. that join media with dissimilar MTUs, but do not support
IPv4 fragmentation and do not send "packet too big" ICMPs?
We answered "NO" to this 15 years ago when we allowed the
approach now specified in RFC 1191 to go forward, and that
decision took a viable design alternative off the table which had
a profound effect on the shaping of the industry.
We're not going to fix this overnight by anything we do here, but
allowing for generality (i.e., not expecting any IPv4 fragmentation
support along the forwarding path) would be an important step
toward restoring a level playing field. Let's not blow it again,
given new opportunities to get things right.
Fred Templin
> Also, we cannot be assured that
> all forwarding nodes will correctly implement IPv4 fragmentation.
> So, we have a very real possibility for black holes here.
Huh? If we can't assume that IPv4 fragmentation works we might as well
assume that IP routing doesn't work and we should be using the postal
service to have this discussion instead of email.