On Sat, Nov 6, 2010 at 2:21 PM, George Bonser <gbonser@seven.com> wrote:
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As for the configuration differences between units, how does that change from the way things are now? A person configuring a Juniper for 1500 byte packets already must know the difference as that quirk of including the headers is just as true at 1500 bytes as it is at 9000 bytes. Does the operator suddenly become less competent with their gear when they use a different value? Also, a 9000 byte MTU would be a happy value that practically everyone supports these days, including ethernet adaptors on host machines.
While I think 9k for exchange points is an excellent target, I'll reiterate that there's a *lot* of SONET interfaces out there that won't be going away any time soon, so practically speaking, you won't really get more than 4400 end-to-end, even if you set your hosts to 9k as well. And yes, I agree with ras; having routers able to adjust on a per-session basis would be crucial; otherwise, we'd have to ask the peeringdb folks to add a field that lists each participant's interface MTU at each exchange, and part of peermaker would be a check that could warn you, "sorry, you can't peer with network X, your MTU is too small." ;-P (though that would make for an interesting deepering notice..."sorry, we will be unable to peer with networks who cannot support large MTUs at exchange point X after this date.") Matt