The MPLS WG Archive

[John Wroclawski <jtw@lcs.mit.edu>]

At 2:24 PM -0400 9/28/00, Curtis Villamizar wrote:
>In message <39D359D5.40A77038@marconi.com>, David Charlap writes:

>>  Although there are a number of RFCs that mention RSVP and ATM together
>>  (2379, 2380, 2381 and 2381), a quick scan of their content didn't reveal
>>  any standard formulae for converting one style of resource
>>  representation to the other.
>
>If you think intserv is somehow important and if you think there is
>good reason to specify mapping of intserv to ATM, write a draft and
>take it to the ISSLL WG (intserv over specific link layers).
>Apparently there wasn't enough interest in the combination of intserv
>and ATM so far.

Actually, this was done ages ago, in the RFC's he mentioned. The 
mapping RFC is quite detailed about how to do a reasonable job, but 
doesn't give a single "right" answer because there are tradeoffs to 
be made, and because "ATM", with all of its myriad QoS options, was 
hardly a single fixed target.

Intserv is primarily about QoS control for applications. Diffserv is 
about many things, including ISP-level differentiated QoS and, in 
some people's view, providing a useful building block for end-to-end 
app-level QoS. The notion that only one of these things is important 
might be a little short-sighted.

Cheers,
John