Multicast PIM neighbors are stateless

When implementing Multicast, PIMrouters become neighbors and exchange multicast routes. PIM neighbors are stateless in the sense that:

  • they do not exchange information in hello packets concerning the mode they are using (dense/sparse)
  • they do not exchange confirmation of neighbor relationship

Administrators are responsible for ensuring the correct mode of operation is configured on the correct interfaces and routers.

https://networklessons.com/multicast/multicast-pim-dense-mode