Do ATM-based Exchange Points make sense anymore?

Mon Aug 12 16:39:00 UTC 2002

>Date: Fri, 09 Aug 2002 14:39 -0700 (PDT)
>From: Mikael Abrahamsson <swmike at swm.pp.se>
>Organization: People's Front Against WWW
>To: nanog at merit.edu
>Sender: owner-nanog at merit.edu
>Delivered-to: nanog-outgoing at trapdoor.merit.edu
>Delivered-to: nanog at trapdoor.merit.edu
>Delivered-to: nanog at merit.edu
>Subject: Re: Do ATM-based Exchange Points make sense anymore?
>
>
>On Fri, 9 Aug 2002, Nenad Trifunovic wrote:
>
>> It appears that for analysis purposes one has to separate access
>> from switching. How much payload one brings to the exchange depends
>> on port speed and protocol overhead. In that light, Frame Relay
>> can bring similar amount of payload as Ethernet (comparable overhead)
>> and preserve good properties of ATM (traffic flow separation). 
>
>What functionality does PVC give you that the ethernet VLAN does not?
>

I am not sure how this question may help analyzing the problem.
For one thing, one can just pose the question the other way around
(what functionality does VLAN give you that does not exist in
Frame Relay (with closed user groups + LMI; that has been around for
quite some time)). 

>What is the current max speed of frame relay in any common vendor 
>implementation (I'm talking routers here).
>
>--

What is current changes. Same technology can be applied to both
Ethernet and Frame Relay encapsulation. Ability to bring more
traffic to the exchange in itself may not be useful if there is
no ability to switch it.

>Mikael Abrahamsson    email: swmike at swm.pp.se
>

nenad