Re: New mailing list documents

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

William StanisLaus wrote:
> 
> Hi Fairhurst,
>      Thanks for the drafts.. I am a new bee.. and have a basic question, Does
> these Encapsulations is to replace DSM-CC... in MPE ??.

Yes - for those networks that are able to change. There is a large
deployed 
base of MPE in broadcast TV service networks - it is unlikely these
deployed 
networks will move away from MPE for the foreseeable future. So co-existance
of the two schemes is important to me. New networks may choose.

There are also a large number of IP-based networks that could take
advantage of
the new encapsulation by a change of driver software. Existing networks may
upgrdae at some time. Again, new networks will have the chance to choose.

>      How do we do MAC filtering in DVB Receivers,  If MPE doesn't have
> information about Destination MAC address ??
> 

MPE has only a ***destination*** Mac address. 

It does not have a source address - which can present issues with LAN bridges,
IPv6 autoconfiguration, and some other scenarios.

It doesn't carry a protocol Type field - which requires use of further headers
to support IPv6 efficiently and other protocols, such as arp.

The requirements draft speaks of such issues - and will be re-issued in
an 
updated format within  a week. 

More questions, comments welcome !

Gorry

> Thanks in advance.
> 
> Best Regards,
> William.
> 
> >===== Original Message From Dr G Fairhurst <gorry@erg.abdn.ac.uk> =====
> >Two new "draft" Internet Drafts are now available for comments.
> >
> >Lightweight Encapsulation rev 01
> >http://www.erg.abdn.ac.uk/users/gorry/ip-dvb/ids/draft-unisal-ipdvb-enc-01.tx
> t
> >
> >Ultra Lightweight Encapsulation (ULE) rev 00
> >http://www.erg.abdn.ac.uk/users/gorry/ip-dvb/ids/draft-fair-ipdvb-ule-00.txt
> >
> >
> >
> >These two drafts capture the comments the authors have received on the
> encapsulation.
> >In answering the comments from people concerning how to implement, we
> discovered
> >there were in fact two varients of the protocol.
> >
> >* One was oriented to a wide range of transport services and was based
> >on PES
> >  packets - it thus could be used in a very flexible way. It employs the AFC
> >  bits and an adaptation field for framing.
> >
> >*  The other approach (ULE)  is based solely on "raw" transport streams.
> >   This does NOT use the adaptation field, and it can NOT be used for
> >PES streams.
> >   It uses a pointer signalled by the PUSI to synchronise framing.
> >
> >To get the best possible feedback, and to avoid confusion when we
> >discuss these,
> >the authors agreed to split the protocols into the two separate drafts.
> >That's why
> >you suddenly see two ID's in place of the one. So, let's debate the
> pros/cons!
> >
> >We can go forward with one of these, both of these in a combined
> encapsulation,
> >or some other scheme - if there are comments, suggestions, please do say
> soon!
> >
> >Gorry & Bernhard.