IP multicast is as an integral technology in networked applications throughout the world. Any network application involving the transmission of the same information to multiple recipients can benefit from the bandwidth efficiency of multicast technology. Multicast represents a key inflection point for the cable industry. While multicast is being used in cable networks today, two key new technologies—the wideband protocol for a Data Over Cable Service Interface Specification (DOCSIS) network and Single Source Multicast (SSM)—are expected to dramatically accelerate multicast deployment.
These technologies will help operators dramatically incease the operational efficiency of the Hybrid Fiber Coax (HFC) network, create a mechanism to accelerate the delivery of advanced services, leapfrog recent announcements of fiber-to-the-x (FTTx) deployments and service, and drive industry agendas for years to come.
This paper is jointly authored by Cablevision Systems Corp., Comcast Corp., and Cisco Systems, Inc. The paper describes multicast deployments at Cablevision and Comcast, highlights other multicast applications, and discusses key challenges. The paper proposes enhancements to DOCSIS specifications that should significantly increase multicast deployments in cable networks.