RE: About some issues (RE: Alcatel Space interest about IP/DVB)

["Harald Skinnemoen" <harald.skinnemoen@nera.no>]

Hello Horst, 

Thanks for your positive response. I believe you're right, at least it
seems so to me at this stage, that THIS group should concentrate as you
say on the encapsulation. However, Gorry (if he agrees to how we think
he may see it...) also has a valid point, in the sense that the
applications must also be considered somehow, as these will define the
real benefit of a lower layer technology. There is no practical effect
(but there may be an academic one) in developing a technology - or
concept- that is not really used. 

Looking further ahead into the future, there may not always be 188 byte
or 53 byte packets to encapsulate things into, and when encapsulation is
considered it may be beneficial to also consider cases where other cell
(packet) sizes may be beneficial. The ETSI BSM group is not limited to
one single air interface technology, and there are a number of good
reasons why future satellite payloads choose other cell-size numbers
than 53 or 188. Could it be possible to define an encapsulation scheme
that was somehow not limited to the MPEG-TS (or ATM)? (I believe this is
in line with conclusions from packet size traffic measurements that both
you and Otto have done). 

/Harald

PS: yes - naturally ETSI (and I) is (are) interested in an update on
your system and it's evolvement. 


> -----Original Message-----
> From: owner-ip-dvb@erg.abdn.ac.uk [mailto:owner-ip-dvb@erg.abdn.ac.uk]
On
> Behalf Of Kearney
> Sent: 18. april 2002 21:30
> To: ip-dvb@erg.abdn.ac.uk
> Subject: Re: About some issues (RE: Alcatel Space interest about
IP/DVB)
> 
> 
> Hello Harald,
> 
> Thanks for your input - and YES we are certainly willing and
interested in
> also working with the respective ETSI group(s).
> I think we should keep the two "layers" apart - the Multicast
Applications
> and the encapsulation and transmission aspects.
> This group, at least as I see it - Gorry might se it differently -
should
> concentrate on the encapsulation, keeping in mind what sort of
> applicatiopns
> might predominantly be using it.
> For multicasting applications we have developed a software system
which is
> noch used for the distribution of Envisat data via satellite and is
> working
> fine. If you want an update on our system (it has changed quite a bit
> since
> we met last time); please let me know.
> 
> Regards,
> --Horst
> 
> ----- Original Message -----
> From: "Harald Skinnemoen" <harald.skinnemoen@nera.no>
> To: <ip-dvb@erg.abdn.ac.uk>
> Sent: Thursday, April 18, 2002 12:35 AM
> Subject: RE: About some issues (RE: Alcatel Space interest about
IP/DVB)
> 
> 
> > Hi,
> >
> > I've been following this discussion from interest from the sideline,
as
> > I am involved with ETSI work that is related to IP over Satellite,
and
> > in particular Multicasting and Addressing & Routing as part of a
> > so-called specialist task force at ETSI.
> >
> > The Broadband Satellite Multimedia group (WG BSM) is involved with a
> > number of issues related to what is discussed here - and yes -
Alcatel
> > is very much involved I this work too.
> >
> > I've got two things...
> >
> > First I would like to invite comments and input on how satellite
> > multicast - in the future - could be made as efficient as possible
with
> > respect to issues like those Horst Clausen points out - spectrum
> > efficiency. Naturally, satellite multicast would need to offer IP
> > multicast compatibility, but one could also imagine a special
satellite
> > solution. I think satellite multicasting also could favorably be
> > combined with caching. This could increase the number of receivers
that
> > could share the same channel, and thus reduce the cost. I would
> > appreciate help to find good references and for those of you who
might
> > want to influence future ETSI standards, I would also be happy to
invite
> > suggestions for specific issues that should be contained in a future
> > standard.
> >
> > Second, and as a natural follow-up of the first, I would also invite
> > this group to not only work with DVB and ATSC, but also ETSI... ;-)
> >
> > /Harald Skinnemoen
> > Recent BSM Chairman, now ETSI Team Leader STF on IP over Satellite.
> >
> > > -----Original Message-----
> > > From: owner-ip-dvb@erg.abdn.ac.uk
[mailto:owner-ip-dvb@erg.abdn.ac.uk]
> > On
> > > Behalf Of Kearney
> > > Sent: 18. april 2002 02:43
> > > To: ip-dvb@erg.abdn.ac.uk
> > > Subject: Re: About some issues (RE: Alcatel Space interest about
> > IP/DVB)
> > > And yes - we should cooperate with the DVB and ATSC groups.
> > >
> > > --Horst Clausen ("kearney")
> > >
> > >
> >