[127195] in North American Network Operators' Group
Re: pls help about mtu setting
daemon@ATHENA.MIT.EDU (William Herrin)
Thu Jun 17 16:53:17 2010
In-Reply-To: <AANLkTilaKU43nhEla0KcFy1Q9MOJo_OW9M3ZtLcxyAdj@mail.gmail.com>
From: William Herrin <bill@herrin.us>
Date: Thu, 17 Jun 2010 09:36:00 -0400
To: Deric Kwok <deric.kwok2000@gmail.com>
Cc: nanog list <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Thu, Jun 17, 2010 at 8:19 AM, Deric Kwok <deric.kwok2000@gmail.com> wrote:
> My DSL company asks me to set the modem 146 2 and my old company used 14 92
> Why it is not standard 1 500?
Because they're wrapping your packet inside another packet that they
then transmit on a line with a 1500 byte MTU. The header on their
packet needs a few bytes, so you can't have them.
Regards,
Bill Herrin
--
William D. Herrin ................ herrin@dirtside.com bill@herrin.us
3005 Crane Dr. ...................... Web: <http://bill.herrin.us/>
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