[AG-TECH] IGMPv3, Source Specific Multicast, fully supported in Windows XP

Bill Nickless nickless at mcs.anl.gov
Fri Aug 16 13:06:29 CDT 2002

At 09:30 AM 8/16/2002 -0700, Jay Beavers wrote:

>I've recently been wondering if for AG-like scenarios we need to use two
>IP addresses, one for "shared" traffic like RTCP SDES notifications and
>another for "filtered" traffic like SSM filtered RTP streams (see my
>message to the IETF AVT alias on this if you're interested).

Consider going beyond only two multicast group addresses.

One group address could be used to discover active sources.

Each active source would transmit to (say) three additional groups.

  - One could be low-rate, postage-stamp size suitable for node ops
    to select from.

  - One would be medium-rate, QCIF size, suitable for putting up on
    the AG display in a "Brady Bunch" scenario.

  - One would be high-rate, 30 fps CIF size, suitable for enlarging
    on the AG display to full size (think view of speaker).

Bill Nickless    http://www.mcs.anl.gov/people/nickless      +1 630 252 7390
PGP:0E 0F 16 80 C5 B1 69 52 E1 44 1A A5 0E 1B 74 F7     nickless at mcs.anl.gov

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