I'm building a multicast network and one of the question I have is if I should configure PIM interfaces in sparse-dense mode or simply sparse-mode. FYI, i'm planning to use PIMv2 and BSR to elect RP.
With PIMV2/BSR, why do I need to setup PIM i/f in sparse-dense mode as recommended in the config guide.
Also, I understand that using the mixed mode, the leafs routers (the ones connected to receiver's segment) may switch over Shared Tree to Shortest Path Tree if both paths to the source aren't the same. The document recommend to configure a SPT delay to prevent this. Why, just not using SM only. That way, leaf router will never find to real source. Am I right ?
Do we met some problems, or lose something, with configuring PIM sparse mode only?
Thanks for your answer.