PIM-SM extension for Source-Specific Multicast through non multicast networks

Abstract

Deployment of multicast in the open Internet is stagnated, mainly as a result of service provider policies and network limitations. To skip the lack of multicast connectivity between receivers and networks that carry traffic generated by multicast sources, the IETF has developed a proposal, called Automatic Multicast Tunnelling (AMT), supported in routers at least from 2011. Even so, it has not brought the necessary momentum to the expansion of multicast. In this report a similar but simpler than AMT proposal to skip the non-multicast gap is described. The basic idea in the proposal is to remove from multicast routing architecture some elements imposed by ASM model, those elements that are not needed for the SSM applications (e.g. Internet TV), but make multicast an 'all-or-nothing' technology.