Subject: RE: QoS in Shared Media

From: "Joel M. Halpern" <[email-masked]>
Date: Mon, 30 Jul 2001 14:02:45 -0400

[Given that I did not start this, I am reluctant to change the target wg, 
but it sure looks like a diffserv discussion, not an MPLS or TE discussion.]

Juha, given that your earlier note said specifically that the technology 
under discussion does support two levels of priority queueing,  it seems 
that you do not have any grounds to complain that it does not support 
diffserv.  It does not support the particular PHB the way you want it 
supported.  One could have a discussion about whether it supports a given 
PHB at all under a specific configuration or under all possible 
configurations.  But that does not mean that the technology does not 
support or is not compliant with diffserv.

Yours,
Joel M. Halpern

At 08:33 PM 7/30/01 +0300, Juha Heinanen wrote:
>fred,
>
>i have no problems whatsoever with diffserv support in regular 801.1q
>ethernet switches that allow me to map the user priority field to wfq
>queues.  rpr doesn't offer this capability.
>
>phb stands for "per HOP behavior".  of course it is possible to support
>diffserv only at the edge, but that doesn't lead to the most efficient
>use of the bandwidth.  it is the same as using cbr vc to connect routers
>together over atm backbone.
>
>-- juha