nanog mailing list archives

Re: Too bigs are sacred, was: Re: IPv6 addressing for core network


From: David Freedman <david.freedman () uk clara net>
Date: Wed, 09 Feb 2011 23:26:46 +0000


Unless every packet you emit is ¾ the minimum MTU (1280), then, you need
to be able to receive TOOBIG messages.

Can you think of a packet type I will emit from my publically numbered
backbone interface which may solicit a TOOBIG that I'll have to care about?

I can only think of three cases, all ICMP:

1. An unreachable of some kind (I don't care if this is delivered or not,
and why would I be sending them from the backbone? Even rate-limited? If I
send them at all this is the responsibility of the edge)

2. A Time Exceed, again, don't care if this is delivered or not

3. A TOOBIG, if I'm getting a TOOBIG in response to my TOOBIG then we all
have bigger problems to worry about :)

Dave.




Owen


-- 

David Freedman
Claranet 
http://www.clara.net



Current thread: