Cell Relay Archive

[Steve Randall <steve@pqm-cons.demon.co.uk>]

In article <33121492.6F0F@nt.com>, Mike Sullivan <mike_sullivan@nt.com>
writes
>Marc Delvaux VH11 wrote:
>> 
>> manfredi@arl.bna.boeing.com wrote:
>> >
>> > In article <33034511.88249813@news.bah.com>,
>> >   martonem@bah.com (Mike Martone) wrote:
>> > >
>> > >       I am conducting a survey and need to knwo if there has been
>> > > any work or studies about voice over ATM.  Mostly related to VBR and
>> > > individual calls vice voice trunking.  Are there any standards
>> > > available or being considered?  What about signalling for calls?
>> > > I can't find anything at the forum, and all message traffic
>> > > (Cell-Relay) is very old.
>> >
>> > Indeed, there is nothing about this voice over ATM topic on the ATM
>> > Forum's Web site. And yet, some months ago, I read a short blurb about a
>> > new group that had formed. A counterpart to MPOA. It was called VTOA or
>> > something (Voice Transport Over ATM). Whatever happened to it?
>> >
>> > In principle, ATM should be capable of this, much like a superset of ISDN.
>> 
>>  There are a lot of work on that subject, mostly using AAL1 as base.
>> There are different chips on the market that supports nx64 kbps mapping
>> into ATM, and ATM forum refers to it as CES (Circuit Emulation Service).
>> My company extended the concept to support more than one nx64 kbps
>> channel
>> per AAL1 connection, via the used of so called composite cells, you may
>> consult:
>> 
>> Alcatel Telecommunications Review - 2nd quarter 1996, "Principle of
>> Composite ATM and its use in Access networks"
>> 
>
>Where can I find documents on the ATM Forum site that describe the
>details of Composite ATM or AAL-CU?

PQM and Delphi Systems Limited are currently studying the possibility of
providing narrowband ISDN connections across an ATM network.  We are
still at the early stages but some (mainly commercial) information can
be found at our website (http://www.pqm-cons.demon.co/.uk).  We would be
happy to answer any technical questions if you call or email us.

We are aware of a VTOA specification which is nearing completion within
the ATM Forum (the VTOA group that you mentioned) and its title is
something along the lines of "Voice and telephony over ATM - ATM
trunking for Narrowband Services"

Hope this helps


Steve Randall
PQM Consultants, Suite C, 17 Moor Street, Chepstow, NP6 5DB, UK
tel: +44 1291 626 180 / fax: +44 1291 626 190
email: steve@pqm-cons.demon.co.uk www: http://www.pqm-cons.demon.co.uk/