IPv6 day and tunnels

Tue Jun 5 22:50:58 UTC 2012

> -----Original Message-----
> From: Masataka Ohta [mailto:mohta at necom830.hpcl.titech.ac.jp]
> Sent: Tuesday, June 05, 2012 3:41 PM
> To: Templin, Fred L
> Cc: nanog at nanog.org
> Subject: Re: IPv6 day and tunnels
> 
> Templin, Fred L wrote:
> 
> >> Infinity? You can't carry 65516B in an IPv4 packet.
> 
> >    2) For tunnels over IPv6, let infinity equal (2^32 - 1)
> 
> You can't carry a 65516B IPv6 packet in an IPv4 packet.

No, but you can carry a ((2^32 - 1) - X) IPv6 packet in
an IPv6 packet. Just insert a jumbogram extension header.

> >> Instead, see the last two lines in second last slide of:
> >>
> >>     http://meetings.apnic.net/__data/assets/file/0018/38214/pathMTU.pdf
> >>
> >> It is a common condition.
> >
> > Are you interested in only supporting tinygrams? IMHO,
> > go big or go home!
> 
> Bigger packets makes it rather circuit switching than packet
> switching. The way to lose.
> 
> Faster is the way to go.

Why only fast when you can have both big *and* fast? See
Matt's pages on raising the Internet MTU:

http://staff.psc.edu/mathis/MTU/

Time on the wire is what matters, and on a 100Gbps wire
you can push 6MB in 480usec. That seems more like packet
switching latency rather than circuit switching latency.

Fred
fred.l.templin at boeing.com 

> 						Masataka Ohta