This is why it is called Any Source Multicast (ASM). A number of applications use the same group for discussions. Cisco's old IP/TV distributed over one group, then had a second group for feedback. So as you typed in a question it was sent to everyone.
David -- http://dcp.dcptech.com -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Riccardo S Sent: Monday, December 17, 2012 12:03 PM To: [email protected] Subject: [c-nsp] Same multicast flow with multiple source I built up a PIM connection to a new multicast provider and I see this provider is sending the same mcast flow with some different sources: -------------- xx#sh ip mroute 224.0.1.114 count IP Multicast Statistics 858 routes using 542426 bytes of memory 705 groups, 0.21 average sources per group Forwarding Counts: Pkt Count/Pkts(neg(-) = Drops) per second/Avg Pkt Size/Kilobits per second Other counts: Total/RPF failed/Other drops(OIF-null, rate-limit etc) Group: 224.0.1.114, Source count: 4, Packets forwarded: 9106926, Packets received: 9106926 RP-tree: Forwarding: 31/0/37/0, Other: 31/0/0 Source: 172.16.89.2/32, Forwarding: 10994/0/30/0, Other: 10994/0/0 Source: 172.16.89.6/32, Forwarding: 10994/0/30/0, Other: 10994/0/0 Source: 172.16.89.3/32, Forwarding: 9073913/27/299/63, Other: 9073913/0/0 Source: 172.16.89.5/32, Forwarding: 10994/0/30/0, Other: 10994/0/0 --------------- Questions: 1) From a conceptual point of view is it correct they send same feed with a lot of different sources ? Usually I always saw one A feed (with sourceA,GroupA) and one B feed (with sourceB,GroupB)... 2) Which can be the reason whether they send one flow with different pkt size (299Byte) and all the other with 30byte pkt size ? 3) Since on my CPE I have static join towards the group in this way I'll get the flow four times with bandwidth exceeded ? Is there a method to us only one flow if identical to the others ? Tks _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/ _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
