From: P729 (p729@cox.net)
Date: Thu Jun 17 2004 - 04:42:55 GMT-3
Paul,
Back in the dark ages of thick (10Base5) Ethernet cable, vampire taps,
separate component MAUs and stiff-as-bamboo AUI cables, the overall bit
error rate was higher than it is today. I believe that, coupled with the
state of embedded logic available to compute and compare the FCS at 10 Mb/s
somehow led to the (DIX?) settling on the 1500 bytes of payload. I'm sure a
lot of math and statistics were involved. And I bet they thought that was
pretty good considering Metcalfe's original Ethernet running at Xerox ran
something like 3 Mb/s with like 512 bytes of payload (hmmm...it's like they
tripled everything...)
Regards,
Mas Kato
https://ecardfile.com/id/mkato
----- Original Message -----
From: "Casey Paul (IE)" <Paul.Casey@o2.com>
To: <ccielab@groupstudy.com>
Sent: Wednesday, June 16, 2004 1:26 PM
Subject: Mtu ethernet
> Hi,
>
> Can someone tell me why the mtu is 1500 on ethernet. Where does this
> number come from.. Or how is it worked out.
>
> I cant believe I still don't know this having reached CCIE and all. I
> dread the day some grad asks me and I have to say I don't know
>
> I have searched the web but can find the specific answer of why 1500..
>
> Any help appreciated.
>
> Thanks
>
>
> / Paul
>
> CCIE 13037
>
> Paul Casey
> Core Networks department,
> Products & Services,
> Technology
> O2 Ireland
>
> Desk: +353 1 6096822
> Fax:+353 86 5 8143310
> Mobile: +353 86 8143310
> Email: paul.casey@o2.com
> Web: www.o2.com
>
>
>
>
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