PIM vs multicast forwarding

[pbarbieri]

I have two routers connected same LAN, one configured with PIM dense mode and the other on multicast forwarding mode. How can I transmit/receive multicast packet between them? Should I need to set the first one in PIM dense mode passive mode ? or change PIM dense in sparse ? or what else?

[Giuseppe Larosa]

Hello @pbarbieri ,

not totally clear however:

you can:

a) configure ip pim sparse-dense mode on RB

b) if you do nothing RB is only a multicsast receiver host or you have configured it with ip igmp join-group G, in this case IGMP is used.

c) if you jave on RB ip pim sparse-mode it may fall back to dende mode by itself after few tens of seconds

Hope to help

Giuseppe

[pbarbieri]

Thank you very much for your reply Giuseppe.
My question is let to communicate two router nodes one configured (Node A) with PIM dense mode and the other (Node B) with multicast forwarding only, same LAN. If Node B start to send multicast address to Node A these packet will be received without problem by the PIM dense? And viceversa the multicast transmit from Node A to Node B can be delivered without PIM Node A adiacencies or hello packets received from Node B without a PIM protocl ? For this reason I thought to set Node A PIM Dense in passive mode, to operate without management control packet like Hello etc.
My problem is that the Node A PIM dense mode configuration can’t be modified because It is not part of our solution, while Node B has been configured with the simple multicast forwarding (where the client of course use IGMP protocol to join to the groups).
Best Regards Pierluigi