Subject: Communication From Study Group 15, Question 4

From: Tom-PT Taylor <[email-masked]>
Date: Sat, 26 Aug 2000 18:45:25 -0500

The following note comes from ITU-T Study Group 15, Question 4.  Study Group
15 deals with physical transport standardization.  I'll let Question 4's
note speak for itself.  In truth, this was addressed to the IETF in general
rather than Megaco, so if someone can suggest more appropriate WGs to send
it to please let me know.

Tom Taylor

We would like to make you aware the Q4/SG15 has initiated a Voice over DSL
(VoDSL) project in order to support various VoDSL end to end services and
thus evaluate new features and technologies that may be required in future G
series xDSL PHY layer standards and welcome any requirements or input you
may have relevant to this effort. At this time, it is not anticipated that
this project will develop a new ITU-T Recommendation, but rather act in
directing any VoDSL related requirements or features to the relevant PHY
layer project. We are currently working on a draft VDSL Recommendation and
the next generation (i.e. "bis" versions) of the ADSL and SHDSL G.series
Recommendations.

The project has identified and are considering the following enhanced
features for future Recommendations:

-       Multi-bearers to enable data and voice (i.e. simultaneous ATM and
STM)
-       ATM dual latency/dual TCs
-       Q mode
-       Signaling, management and control support
-       Seamless rate adaptation
-       Repartitioning
-       Line powering (provide voice during remote power failure)
-       QoS (error rate/latency ...)
-       Network Timing Reference (NTR) - synchronization
-       All digital loop (upstream capacity improvement)
-       Co-operation between PHY, transport and voice layers

We welcome your input and any guidance you can provide to make the Q4/SG15
VoDSL project result in improved future G.series xDSL Recommendations.
Currently approved G.series Recommendations can be found at www.itu.ch.