[BC] IP Multicast

[Tom Hartnett]

Well it's possible that Verizon supports it, but unless you're 
connecting to a specially Verizon assigned class D address 
range  (<http://224.0.0.0>numericlinkwarning 224.0.0.0 through 
<http://239.255.255.255>numericlinkwarning 239.255.255.255) on the 
encoder, and then connecting to the same address range with each 
decoder, you're not IP Multicasting. I can't explain your math either 
but my feeling is you're multi-streaming.

Tom Hartnett
Technical Director
Comrex

Message: 31
Date: Mon, 04 Dec 2006 18:24:06 -0500
From: "Dana  Puopolo" <<mailto:dpuopolo at usa.net>dpuopolo at usa.net>
Subject: Re: [BC] RE: Multiple ISDN

I dunno...

I'm doing quite well using multicast.

Perhaps Verizon's private network supports it - as all my Internet circuits
are Verizon DSL. All I know is that I've run half a dozen 80K streams off a
single 384K upload...
and the math just doesn't add up if each one needs their own bandwidth.

-D

------ Original Message ------
Received: Mon, 04 Dec 2006 12:18:56 PM EST
From: "Tom Hartnett" < <mailto:hartnett.tom at gmail.com>hartnett.tom at gmail.com>

Hi Dana,

I suspect there may be some confusion here. Whether a stream is UDP or TCP,
there's no inherent broadcast protocol built in. To distribute streams to
more than one place, one can either:
1) Multistream--build an independent udp or tcp unicast stream to each user.
This is how virtually all streaming servers work, including your Barix and
our ACCESS. ACCESS is specified to deliver 9 streams in all modes, but can
do over 50 in some modes. Note to do 50 streams you need 50x upload
bandwidth.
2) IP Multicast-- Build one stream and send it to a special multicast
address. Receivers will also attach to a special multicast address and get
their streams, but it is distributed by the network. By and large, most
publicly available Internet *does not* support IP Multicast, although it is
supported in ACCESS for use on LANS and WANS.