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Re: Differences between INT and MMT tables for address resolution?



As I recall, and my version of history could be entirely wrong - so
I rely on other list members to correct this - in 2000, there were two 
proposals within the DVB community for study, as possible extensions 
to DVB-RCS, but sort-of tackling general address resolution issues 
for multicast over DVB.

Both used DVB tables to map IP multicast addresses to a DVB TS.

(i) The multicast PID assignment method (MPAM)

In MPAM, the receiver is explicitly told in a unicast TIM, 
which PIDs it must add or remove from its active PID list. 

(ii)  The multicast PID mapping method (MPMM). 

In MPMM, the multicast group ID, e.g. multicast IP destination address, 
is mapped to a PID and broadcast in a PID map (MPM) to all receivers. 
When an end host wishes to join a multicast group, the receiver performs
a lookup in the multicast PID mapping information to resolve
the group and then to add the TS to its active PID list. 

In what I saw, neither specified (S,G) information, since the table
was simply a list of IP multicast destination addresses, i.e (*,G).

Would one of the authors, or people in DVB or RCS-work like to say 
more???

Gorry


toni.paila@nokia.com wrote:
> 
> Good question, Frank.
> 
> Indeed, I have not heard of MMT. Perhaps you can enlighten us all!
> 
> >From my point of view, INT is all that you need. Both unicast and multicast (ASM/ISM and SSM). And for MAC, IPv4 and IPv6.
> 
> BR,
>  Toni
> 
> > -----Original Message-----
> > From: ext Frank.Zeppenfeldt@esa.int [mailto:Frank.Zeppenfeldt@esa.int]
> > Sent: 19 December, 2002 14:39
> > To: IP-dvb@erg.abdn.ac.uk
> > Subject: Differences between INT and MMT tables for address
> > resolution?
> >
> >
> > Before delving into the DVB archives, does somebody know:
> >
> > a. Where the Multicast Map Table is officially defined ? Is
> > there a DVB
> > reference ?
> >
> > b. What is the relation between the INT (IP/MAC Notification
> > Table) , as
> > defined in ETSI EN Draft 301 192 v1.3.1 (2002-12) ? In
> > addition to offering
> > unicast/MAC streams/platform concept, is it  making the MMT
> > obsolete  ? Is
> > there a reference to minutes of some DVB meeting that
> > explains the relation
> > between the two ?
> >
> > My understanding is that EN 301 192 v1.3.1 (DVB data
> > broadcasting)  document
> > now includes the document referenced in Gorries report from
> > Atlanta (ETSI EN
> > drTS 102 00X V0.4.2 (2002-07) "Specification for IP
> > Notification in DVB
> > Systems Use of the IP/MAC Notification Table").
> >
> >
> > Regards, Frank
> >
> >
> >
> >