IP over DVB Discussion at SLC 52nd IETF Meeting

Wednesdsay 12th December Afternoon Session II: 15:30 - 17:30
Fountainbleu Room

ORGANISERS: Gorry Fairhurst (Aberdeen University, UK)
Andrew Valentine (Hughes Network Systems Ltd, UK)

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MEETING OBJECTIVE/DISCUSSIONS

This was not an official IETF BOF and therefore an unofficial meeting of
IETF members that are interested in the area of IP over DVB. There is
currently no IETF WGs on this subject. The meeting was well attended with
around 20 IETF members and about 92 people on the mailing list. A web-site
has been set up with background information in the area and can be found
at http://www.erg.abdn.ac.uk/users/gorry/ip-dvb/.

At several times during the meeting the opinion was expressed that the
success of this activity will depend upon the level of support from DVB
equipment manufacturers. Andrew Valentine also stated several times that
DVB had renewed interest in this area and were holding a meeting at the
end of January to discuss IP. He was hoping to attend the meeting and
find a way for the DVB groups and this group to interwork and exchange
ideas/documents.

AGENDA

1. Introduction

2. Background- Present/discuss background to the need for work in this
area.
The CoSTAR Interoperability Test-bed (Arun Welch IGI Consulting Company)
- Running test bed over ACTS, using DVB to monitor end-to-end
performance.
- A number of active participants in the CoSTAR test-bed (can loan
equipment to the test-bed for interoperability testing)
Copies of slides at: SLC-CoSTAR.pdf

IP/DVB (Regis J Crinon Intel Corporation)
- A number of existing HW/SW that support DVB transports
- On the head-end, SMPTE 325M and two recommended practices for DVB
transport streams
- Existing environment standard (ATSC IP Multicast with sessions
T3-544)
- There are a number of different standards what are similarities
and differences?
- Would like to define a more efficient IP encapsulation method than
MPE, would prefer to emphasize IP over MPEG2 as opposed to IP over DVB.
Copies of slides at: SLC-INTEL.pdf

IP over DVB-[S/T] (Patrick Cipiere UDCast)
- Differences between DVB-S/T (provides satellite frequencies at

http://www.lyngsat.com

DVB-S is stationary; DVB-T is somewhat mobile.
- Gave a general overview of the MPEG2 packet structure.
- MPE can be considered as layer 2 or above layer 1, because of LLC.
- Section packing is supported in all hardware drivers.
- Low-end hardware can listen and filter 40Mbit/s traffic from a satellite downlink,
where filtering is done in driver along with section encapsulation.
- High-end cards does PID filtering and encapsulation in hardware/firmware.

Copies of slides at: SLC-UDCAST.pdf

3. Requirements Internet Draft
Draft frame works document is available at the URL provided below:
http://www.erg.abdn.ac.uk/users/gorry/ip-dvb/ids/draft-fair-ipdvb-req-00d.txt

The requirement document authors are Gorry Fairhurst, Bernhard
Collini-Nocker and Horst Clausen.

Important context:
1) DVB can work at low and high rates (tens of Mbps)
2) DVB has been defined for many PHYs
3) Not all DVB links carry TV
4) Some DVB links are two-way (duplex)

Individual submissions of IDs to IETF are needed from this effort. The
information and types of documents that are under consideration should
include at least:

Info RFCs
Requirements/frameworks

Standards Track RFC(s)
Encapsulation
Address Resolution
Multicast Operation

Points of debate:
1) Efficient overhead
2) Not having the source MAC in the MPE encapsulation is a problem,
as reported by an attendant.
3) What headers should be included?
4) IPv6 issues?
5) Transition to a new standard?
6) How should the PID (MPEG-2 TS) be used?
7) How do we support multiple MPEG-2 muxes?
8) Use of DVB tables?
9) How much can be done at the IP / sub IP level?
10) Multicast issues?

Future issues:
1) DVB-RCS issues?
2) Regenerative satellites?
3) What else is going to be needed?
4) How to handle QoS?

Would like to get contributions on efficient encapsulation for IP over
DVB. Once the different contributions have been reviewed and discussed,
the group can then combine these ideas into a single document.

4. Proposed IP Over DVB Charter

1) Specify requirements/framework that may be used as a basis for the
WG activity. Consideration of upgrade path / transition from current
MPE-based systems will be considered.
2) Investigate and design an efficient encapsulation method for
transporting IPv4 and IPv6 over DVB based on (1)
3) Consider address resolution and multicast group membership
reporting based on (1).

During the charter discussion it was agreed to widen the scope of the
group to cover IP over MPEG2-TS. This would allow groups such as ATSC and
ARIB to also participate as they also have a strong interest in this area.

At the end of the meeting the organisers asked the attendees if they would
support an official BOF; the answer was an overwhelming 'YES'. The BOF
will be held in March 2002 at the 53rd IETF, if all goes according to
plan!