[158756] in North American Network Operators' Group
Re: Why do some providers require IPv6 /64 PA space to have public
daemon@ATHENA.MIT.EDU (Mikael Abrahamsson)
Sun Dec 9 22:29:11 2012
Date: Mon, 10 Dec 2012 04:28:56 +0100 (CET)
From: Mikael Abrahamsson <swmike@swm.pp.se>
To: Ryan Malayter <malayter@gmail.com>
In-Reply-To: <8B309A82-BD53-4023-8E80-01C21101AB96@gmail.com>
Cc: North American Network Operators' Group <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Sun, 9 Dec 2012, Ryan Malayter wrote:
> But where are all these horrifically unreliable tunnels?
6to4 is one example.
I'd say since PMTUD is too often broken on IPv4 (if the tunneling routers
even react properly to PMTUD need-to-frag messages for their tunnel
packets) in combination with some ISPs supporting jumbo frames internally,
makes a lot of tunneling work badly.
So you might use tunnel broker tunnels that handle tunnel packet
fragmentation for 1500 byte payload over 1500 byte infrastructure and that
makes you feel they are reliable.
My tunnels to my home where I run routing protocol over the tunnels to two
separate tunnel routers at the ISP end (I control all endpoints) plus
running ipv6 MTU 1400 in my home to avoid PTMUD for all TCP connections is
also a very reliable setup, but I'd rather have native IPv6 and 1500 MTU
end-to-end.
--
Mikael Abrahamsson email: swmike@swm.pp.se
