Jumbo Frames (was Re: MAE-EAST Moving? from Tysons corner to reston VA. )

["Bora Akyol" <akyol () akyol org>]

Same question once again.

As long as most end users are running Ethernet, Fast Ethernet, DSL or Cable
Modems, what is the point of jumbo frames/packets other than transferring
BGP tables really fast. Did any one look into how many packets are moved
through an OC-48 in 1 seconds. (approx. 6 million 40 byte packets). I think
even without jumbo frames, this bandwidth will saturate most CPUs.

Jumbo frames are pointless until most of the Internet end users switch to a
jumbo frame based media.

Yes, they look cool on the feature list (we support it as well). Yes they
are marginally more efficient than 1500 byte MTUs ( 40/1500 vs 40/9000). But
in reality, 99% or more of the traffic out there is less than 1500 bytes. In
terms of packet counts, last time I looked at one, 50% of the packets were
around 40 byte packets (ACKs) with another 40% or so at approx 576 bytes or
so.

What is the big, clear advantage of supporting jumbo frames?

Bora



----- Original Message -----
From: "brett watson" <bwatson () mibh net>
To: "Richard A. Steenbergen" <ras () e-gerbil net>
Cc: "RJ Atkinson" <rja () inet org>; <nanog () merit edu>
Sent: Saturday, June 17, 2000 11:11 PM
Subject: Re: MAE-EAST Moving? from Tysons corner to reston VA.


> > On Sat, 17 Jun 2000, RJ Atkinson wrote:
> >
> > > Which OSs don't yet support this ?
> >
> > Not OS, drivers. Pick your favorite OS with GigE support, grep jumbo the
> > drivers section. In a few cases the unix drivers support jumbo frames
and
> > the reference vendor drivers do not, in a couple its the other way
around.
> > I see its getting better though, there is more support then there used
to
> > be the last time I looked.
>
> you'd be surprised how many vendors aren't even considering supporting
> jumbo frames, or worse don't understand why you'd want to.
>
> several vendors of optical gear (dwdm) i've run into lately weren't
> even going to do it and didn't know why they should.  this only
> applies to vendors doing native GE, not vendors going true transparent
> optics.
>
> -b