Do you have a Wireshark capture of your own device on your own test
network?  It would be a useful baseline.

Multicast is very hard to interrupt.  The scenarios are;

1.  their server _decides_ to interrupt the stream as a result of what
it receives from your device, even if there was no intent to
communicate, or;

2.  their server doesn't get a chance to transmit because your device
is using all available bandwidth.

Their Wireshark capture can help with analysis; in the first scenario
it may show you the packets that lead to the stream interruption, and
in the second scenario it may show bogons [1] from your device.

Another test would be to see if the multicast stream resumes the
instant your device is physically removed from the network.

[1]   http://www.catb.org/jargon/html/B/bogon.html

On Tue, Aug 25, 2015 at 08:30:05PM -0700, Harold Hallikainen wrote:
> Thanks for giving it more thought! I've requested a WireShark capture. I
> have not dealt with multicast before. Here's a brief description of what
> they're doing:
>=20
> The multicast content is streaming from the Server on the network
> (172.16.1.165).  Multicast address is 239.3.2.1 port 1234. There
> are three test clients (172.16.1.201),  (172.16.1.207), and (172.16.1.213=
).
>=20
> My device initiates a TCP connection to a specified IP address and does
> some HTTP requests. I DO have announce enabled, so my device responds to
> broadcast UDP requests on whatever port that is (30303 or something like
> that) that have the appropriate string.
>=20
> The customer is saying their multicast stream is interrupted if my device=
s
> are on the network.
>=20
> I'll see if they can get a Wireshark capture.
>=20
> Thanks!
>=20
> Harold
>=20
> Harold
>=20
>=20
> > Having slept on it, there is one strange scenario ... and I'm
> > speculating wildly here ... if there is a device on the network using
> > a multicast IP address as a source address for a packet which is
> > addressed to your device, ... then the response by your device will
> > differ according to whether the #define is set or not.
> >
> > But I've never encountered a host using a multicast IP address as a
> > source address.
> >
> > --
> > James Cameron
> > http://quozl.linux.org.au/
> > --
> > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
> > View/change your membership options at
> > http://mailman.mit.edu/mailman/listinfo/piclist
> >
>=20
>=20
> --=20
> FCC Rules Updated Daily at http://www.hallikainen.com - Advertising
> opportunities available!
> Not sent from an iPhone.
> --=20
> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist

--=20
James Cameron
http://quozl.linux.org.au/
--=20
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View/change your membership options at
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.