Re: [Diffserv-interest] dumbell topology

Fred Baker <fred@cisco.com> Thu, 16 August 2007 20:31 UTC

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From: Fred Baker <fred@cisco.com>
Subject: Re: [Diffserv-interest] dumbell topology
Date: Thu, 16 Aug 2007 13:28:46 -0700
To: Kathleen Nichols <nichols@pollere.com>
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On Aug 16, 2007, at 12:31 PM, Kathleen Nichols wrote:

>
> I can't help asking: Why would you *want* to use a dumbbell?

in deployed networks, who *doesn't* use a dumbbell?

Generally speaking, folks use LANs in their local infrastructures.  
These are frequently 10/100 Ethernet, either because the switch  
doesn't support gigabit or the host doesn't, but there is use of  
gigabit and and ten gig as well. Within commercial ISPs, optical  
technology is similarly usually in the gigabit range. But the access  
paths are a *lot* slower - residential  and smaller-company access is  
on the order of a megabit or less, and larger businesses use tens to  
hundreds of megabits.

the access makes it a dumbbell.

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