Re: Internet Exchanges supporting jumbo frames?

[Frank Habicht <geier () geier ne tz>]

Hi,

On 3/10/2016 9:23 AM, Tassos Chatzithomaoglou wrote:
> Niels Bakker wrote on 10/3/16 02:44:
> > * nanog () nanog org (Kurt Kraut via NANOG) [Thu 10 Mar 2016, 00:59 CET]:
> > > I'm pretty confident there is no need for a specific MTU consensus and not all IXP participants are obligated to 
> > > raise their interface MTU if the IXP starts allowing jumbo frames.
> >
> > You're wrong here.  The IXP switch platform cannot send ICMP Packet Too Big messages.  That's why everybody must 
> > agree on one MTU.
> Isn't that the case for IXP's current/default MTU?
> If an IXP currently uses 1500, what effect will it have to its customers if it's increased to 9200 but not announced 
> to them?

none.
everyone has agreed on 1500. it is near impossible to get close to
everyone to agree on 9200 (or similar number) and implement it (at the
same time or in a separate VLAN) (Nick argues, and i see the problem).
The agreement and actions of the (various) operators of L3 devices
connected at the IXP is what matters and seems not trivial.
They are not under one control.

Frank