We're Sorry, Full Content Access is for Members Only...

If you like to keep on reading, Become a Member Now! Here is why:

  • Learn any CCNA, CCNP and CCIE R&S Topic. Explained As Simple As Possible.
  • Full Access to our 644 Lessons. More Lessons Added Every Week!
  • Content created by Rene Molenaar (CCIE #41726)

466 Sign Ups in the last 30 days

100% Satisfaction Guaranteed!
You may cancel your monthly membership at any time.
No Questions Asked!


Forum Replies

  1. 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

  2. Hi Laz,

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


  3. Hello Michael

    An excellent explanation of these notations can be found at the following link:


    Note here that the (S, G) notation is used to refer to the shortest path tree (SPT) distribution tree. This is when no single shared root of the tree is being used. In other words, this is when no Rendevous Point (RP) is being used.

    Whenever an RP is being used, then the notation changes to (,G), which refers to the fact that a Shared Distribution Tree (SDT) is

    ... Continue reading in our forum

  4. Thanks for the reponse Laz, I understand the difference between SDT & SPT but here’s where I get confused:

    Even when running PIM dense mode with no RP, when I issue ‘show ip mroute’ I will see (, AND I will also see (, The (, will be for a device that has registered via IGMP to receive that multicast group. In this instance it doesnt have any link to sparse mode and RP as it is an IGMP join message.

    So when is it used by IGMP join and then PIM Sparse mode as SDT? I’m confused by the notation (*, and its meaning

    ... Continue reading in our forum

37 more replies! Ask a question or join the discussion by visiting our Community Forum