Re: Scenarios for draft-fair-ipdvb-req-04.txt

[Gorry Fairhurst <gorry@erg.abdn.ac.uk>]

Trying to draw together the security inputs suggests a general need for more
precise scenarios that exhibit different properties/requirements, this also
will be useful when describing other protocols used to build the IP over
MPEG service. Can I ask for inputs to help draw up this list of scenarios?


Here is a start (from looking through the mailing list):


1) Art's recent inputs to the security thread seem oriented to TV-style
networks ("contribution" and "broadcast").  In the broadcast context,
transmission goes to many Receivers (unidirectional star) and IP packets can
be integrated with TV/radio transmission channels. The broadcast part of the
networks are characterised by a large population of receivers that may
receive the same bit stream.

2) Laurent Claverotte's focus was oriented to two-way satellite IP provision
- where the MPEG transmission network provides a physical & link technology
for a two-way star IP network (DVB-RCS). Organisation is currently usually
based around a star toplogy, in which a central hub station acts as the
gateway to the wider Internet.

Other scenarios include:

3) Point-to-point network links can be used to connect between Internet
Service Providers - these typically have no TV content - and use MPEG as
just a physical & link technology, many use the same technology (e.g. DVB-S)
in both directions. Such networks are characterised by a small number of
receivers for each transmitted bit stream.

4) Point-to-multipoint networks where the outbound link uses broadcast
technology (possibly shared with TV/radio?) and the return link uses some
other technology (e.g. Modem, LMDS, GPRS, ...).  Such networks could utilise
UDLR protocols for routing [RFC3077].

Are there more important cases, that I have missed?

What about cable networks, cellular DVB-T, mobile DVB-T, mesh DVB-RCS?


A typical usage could be:

End-host<-->IP network<-->IP network
                               |
                          IP gateway<->MPEG-2 network<-> Receiver
                                                            |
                                          End-host<-->IP network

Where the middle line represents the "MPEG-2" part of the internet path, in
this case  the end users are the people using the end-hosts.


Gorry Fairhurst.