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Re: exchange point media (was: Re: MAE-EAST Moving? ...)

  • From: Richard A. Steenbergen
  • Date: Fri Jun 16 04:12:23 2000

On Thu, 15 Jun 2000, Simon Lockhart wrote:

> 
> >The other question is what is the actual capability of the GigaE cards in
> >a cisco box?  I have been told (not played with GigaE on cisco yet and for
> >that matter, neither has the person who told me) that it is limited to
> >around 400Mb/s.
> 
> On a 7xxx Cisco, yes, it's limited to 400Mb/s, due to limitations on the
> interface to the backplane (or VIP2 in the 75xx).
> 
> On the Cisco 12000, the backplane interface is 2.5Gb/s, so the GigE cards
> can run at full speed.

On 12008's and 12012's with older SFCs. The backplane on the 12016
supports 10Gbps each direction. Interestly, Cisco is doing 3 port gige
cards which oversubscribe the older SFCs. Last I heard they were doing
updated SFCs for the 12012 but not the 12008.

At any rate, Cisco does support jumbo frames, which can be up to 9k (just
set the mtu to 10240), but if I recall correctly jumbo frames were not
standard in 802.3z? http://grouper.ieee.org/groups/802/3/

-- 
Richard A Steenbergen <[email protected]>   http://www.e-gerbil.net/humble
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