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Forum Replies

  1. Hi Benjamin,

    The PIM join starts at the bottom and works it way up the tree:


    This is the RPT (Root Path Tree) towards the RP.

    The bottom router receives an IGMP membership so it will send a PIM join.

    Once this has been established, we might switch to the SPT (Shortest Path Tree). The router that is switching to the SPT will send a PIM join towards the source…

    The source IP is indeed learned by looking at the IP header.


  2. Hello Nani

    Great to have you here! We’re happy that you find the forum and Rene’s lessons helpful in your studies!

    In the output of the show ip mroute command, you will see various multicast address groups that exist within the mroute table. For each of these, there is a single incoming interface.

    ... Continue reading in our forum

  3. Hi Laz,

    Thanks for your in details explanations for each question. Yes it is helpful.


  4. Hello Madhu

    This is an excellent question, and it shows that you are thinking critically and combining multiple concepts in your mind. If you take a look at the Multicast RPF (Reverse Path Forwarding) lesson, you will note that when the RPF check fails, it is because there is multicast traffic being received from an RPF neighbor that is not specified in the multicast routing table. Multicast traffic is received from IP address “X” when the RPF neighbor is actually “Y” in the multicast routing table.

    In the example you are referring to, you will notice that yo

    ... Continue reading in our forum

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