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RE: RINA - scott whaps at the nanog hornets nest :-)
From: "George Bonser" <gbonser () seven com>
Date: Sun, 7 Nov 2010 00:54:40 -0700




Oh, come on. Get real. The world TCP speed record is 10GE right now,
it'll
go higher as soon as there are higher interface speeds to be had.

You can buy 100G right now.  I also believe there are some 40G
available, too.

Also, check this:

http://media.caltech.edu/press_releases/13216

That was in 2008.  

 
I can easily get 100 megabit/s long-distance between two linux boxes
without tweaking the settings much.

Until you drop a packet.  I can get 100 Megabits/sec with UDP without
tweaking it at all.  Getting 100Meg/sec San Francisco to London is a
challenge over a typical Internet path (i.e. not a dedicated leased
path).

Or they might tweak some other TCP settings and get 30 meg/s with
existing
1500 MTU. It's WAY easier to tweak existing TCP than trying to get the
whole network to go to a higher MTU. We do 4470 internally and on
peering
links where the other end agrees, but getting it to work all the way
to
the end customer isn't really easy.

I guess you didn't read the links earlier.  It has nothing to do with
stack tweaks.  The moment you lose a single packet, you are toast.  And
there is a limit to how much you can buffer because at some point it
becomes difficult to locate a packet to resend.  *If* you have a perfect
path, sure, but that is generally not available, particularly to APAC.

But in a transition some end systems will have 9000 MTU and some parts
of
the network will have smaller, so then you get problems.

Which is no different than end systems that have 9000 today.  A lot of
networks run jumbo frames internally now. Maybe a lot more than you
realize.  When you are using NFS and iSCSI and other things like
database queries that return large output, large MTUs save you a lot of
packets. NFS reads in 8K chunks, that can easily fit in a 9000 byte
packets.  It is more common in enterprise and academic networks that you
might be aware.



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