[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Call for the ipdvb WG to adopt: draft-fairhurst-ipdvb-ule-ext-01.txt
Dear Gorry,
thanks for your initiative.
I read your draft carefully and found it very interesting.
However, I have the feeling that MPEG-2 TS is gradually abandoned and we
are paving towards an "all-IP" environment.
The introduction of "generic stream" shows exactly this tendency, and I
believe that the same philosophy is to be followed in the 2nd generation
terrestrial specs also (DVB-T2).
Surely, providing a support for TS packets encapsulation within GSE or
ULE might provide a backwards-compatibility, but IMHO it is of
questionable usability. MPEG-2 TS packets can be directly mapped in a S2
BBframe, without the use of extra overhead.
At NCSR "Demokritos", we have a strong experience in IP/DVB and are
currently leading a European research activity which is to investigate
DVB-T2. In the latter, our team is devoted to research regarding
baseband formatting and upper-layer issues.
My proposal: we can go on with your draft, since it strengthens the role
of GSE and ULE, making them more flexible. Indeed, the feature of
grouping data belonging to the same NPA is quite attractive.
But I believe it is also important to look into how the ipdvb WG can
benefit from the advance of next-generation terrestrial standards.
Looking towards the "shutoff" of the MPEG-2 TS, possible issues for
research could be:
- the full migration of the MPEG signalling (PSI) to IP/GSE level
- the transfer of the DVB-H Time Slicing feature in IP/GSE level
- the transfer of the transport-layer FEC (MPE-FEC) in IP/GSE level.
and generally any issue which may stem from the use of Next-gen DVB as a
"transmission system for broadcasting IP datagrams"
I would be more than willing to participate in any activity covering
such issues.
Thanks and best regards to all,
George
---------------
Dr. Georgios J. Gardikis
Associate Researcher
Digital Telecommunications Lab
NCSR "Demokritos", Institute of Informatics and Telecommunications
Ag.Paraskevi, Athens, Greece
Tel: +30 210 6503108
Fax: +30 210 6532175
Web: http://aias.iit.demokritos.gr/~gardikis
Email: gardikis@iit.demokritos.gr
O/H Gorry Fairhurst έγραψε:
As WG Chair, I request the ipdvb list to consider whether the WG is
ready to adopt the following individual ID (Internet Draft) as a
working group ID, with an intention to develop this into a RFC.
This particular draft was introduced to support a standard in
preparation by the DVB Forum. The aim is to make the 2nd Generation
Physical Layer present an interface via the Generic Stream
Encapsulation that is consistent with ULE (e.g. uses the IANA
registry), so that both can benefit from common extension modules:
header compression, etc (should these be defined).
PLEASE DO read the draft below and offer email comments on the
suitability or progression to an RFC and the technical content. ALL
comments are welcome. Email received before the 25th January 2007 will
be used to inform the decision about whether to make this a WG Draft.
WG documents should no longer be regarded as the property of the
individuals who originally authored them - the working group as a
whole must decide how they are shaped, and to see the document to
a successful conclusion. If adopted, the Internet Draft will be
renamed to start with the filename draft-ietf-ipdvb..., and will be
listed on the IETF web page for this WG.
Best wishes,
Gorry Fairhurst
(ipdvb WG Chair)
----
Title : Extension Formats for Unidirectional Link Encapsulation (ULE)
and the Generic Stream Encapsulation (GSE)
Author(s) : B. Collini-Nocker, G. Fairhurst
Filename : draft-fairhurst-ipdvb-ule-ext-01.txt
Date : 2007-1-11
This document describes a set of Extension Headers for the
Unidirectional Lightweight Encapsulation (ULE). The Extension Header
formats defined in this document provide new extensions that are
common extensions to both ULE and the Generic Stream Encapsulation
(GSE) defined by the second generation framing structure DVB-S2
standard (Channel coding and modulation systems for Broadcasting,
Interactive Services, News Gathering and other broadband satellite
applications).
A URL for this Internet-Draft is:
http://www.ietf.org/internet-drafts/draft-fairhurst-ipdvb-ule-ext-01.txt