Cable Plugs Into SIP & IMS with New Spec Release

CableLabs issued Release 2 of its PacketCable specification suite, paving the way to add session initiation protocol (SIP) and IP multimedia subsystem (IMS) technology to MSO networks. Once labeled PacketCable 2.0 by CableLabs, the new specifications were rechristened Release 2, a sizzling semantic shift. Not stopping there, PacketCable 1.0 and 1.5 have been renamed Release 1.0 and Release 1.5, in part to mimic IMS labeling. Holy nomenclature changes! At least the PacketCable Multimedia (PCMM) moniker is still with us. See www.packetcable.com for the latest. With Release 2.0, the North American cable industry comes full circle in IP communications. Back in 1999 there was a vigorous debate within PacketCable about whether to implement a centralized POTS-style architecture based on MGCP, or a more flexible multimedia platform aligned with SIP. Cable's Bellheads won that debate, selecting a MGCP-based scheme, Network Call Signaling (NCS), for PacketCable 1.0 (oops, that's Release 1.0 now). Release 1, which essentially enables MSOs to offer POTS via IP, didn't make it out of the lab for nearly five years. The platform is fully deployed now and delivering service to more than 5 million cable IP phone customers. Problem is, during that five-year hardening period, SIP stole the show in every service provider segment except cable. Now MSOs are playing catch-up in SIP and IMS with Release 2. PacketCable Release 2 is based on IMS Release 6 from the 3rd Generation Partnership Project (3GPP). IMS Release 6 is wireless-centric, so CableLabs has added some cable-specific enhancements in its Release 2. This includes QoS for IMS-based applications on DOCSIS access networks via PCMM; supporting NAT and firewall traversal; as well as enhanced access signaling security and authentication mechanisms. When it's all said and done, Release 2 will enable MSOs to offer enhanced IP communications services, such as video telephony, integrated landline and mobile offerings, cross-platform applications like caller ID on the TV, presence-based services, and IP PBX solutions for business users. SIP is finally coming to cable. Better late than never.