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<TITLE>Source specific multicasting (SSM) example?</TITLE>
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<P><FONT SIZE=2 FACE="Arial">Hi, there.</FONT>
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<P><FONT SIZE=2 FACE="Arial">I was wondering if there is any information or examples on how to use Twisted to perform a SSM operation. I am new to Twisted and to Python.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">In C, I believe one would use the setsocketopt() to specify the joining to a multicast group (G) to a specific source (S):</FONT></P>
<P> <FONT SIZE=2 FACE="Arial">setsockopt(sock,…, IP_ADD_SOURCE_MEMBERSHIP, (S, G, iface), …)</FONT>
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<P><FONT SIZE=2 FACE="Arial">I believe that Python itself has analogous socket calls and could do this using a UDP socket. </FONT>
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<P><FONT SIZE=2 FACE="Arial">I read the Multicast UDP example on Twisted here: <A HREF="http://stderr.org/doc/twisted-doc/howto/udp.html#auto3">http://stderr.org/doc/twisted-doc/howto/udp.html#auto3</A></FONT>
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<P><FONT SIZE=2 FACE="Arial">This shows how to do a normal multicast UDP situation with Twisted (i.e. a process will receive UDP traffic from ALL sources registered to the IGMP group). </FONT></P>
<P><FONT SIZE=2 FACE="Arial">So, if there were UDP three sources (e.g. A, B, and C) registered to the IGMP group, I would like to find a way for my client to only receive data from source B.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">I believe that I can get information using a SDP/SAP using a simple UDP server listening on the appropriate port. So, the only thing that I am missing is how to register to a group for a specific source. I am not sure if the joinGroup() method will allow for this. </FONT></P>
<P><FONT SIZE=2 FACE="Arial">Thanks.</FONT>
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<P><FONT SIZE=2 FACE="Arial">-Rodney Lott</FONT>
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