PacketCable™ — Project Primer
Overview
PacketCable™ is a CableLabs®-led project initiated by cable operators with the objective of defining a QoS-enabled, IP-based services delivery platform which utilizes the capabilities of the DOCSIS access network. In order to accomplish this broad objective, the PacketCable project consists of several sub-projects, each of which accomplishes a sub-set of the overall project objectives. Currently, PacketCable consists of the following: PacketCable 1.0 and 1.5, PacketCable Multimedia, and PacketCable 2.0.
  • PacketCable 1.0 and 1.5: An End-to-End architecture for the delivery of digital voice telephone service over a DOCSIS cable network.
  • PacketCable Multimedia: An application independent QoS architecture for real-time IP based services.
  • PacketCable 2.0: An End-to-End architecture for the delivery of enhanced residential digital voice services (including video telephony), and mobility services which also supports feature integration across service platforms.
Each project area is described in further details below.

PacketCable 1.0 and 1.5
PacketCable 1.0 defines an end-to-end architecture for the delivery of residential voice telephony over IP, commonly referred to as digital voice. The end-to-end architecture describes a complete system that includes: device provisioning, call signaling, event messaging (accounting), configuration management, QoS, PSTN interconnection, and security.

Several factors differentiate PacketCable residential voice telephony services from traditional “IP telephony” services. For example:
  • PacketCable is a phone-to-phone service rather than a personal computer-based telephony service.
  • PacketCable services are guaranteed priority delivery on the DOCSIS access network ensuring a consistent, high-quality service.
  • PacketCable services are not delivered over the public Internet. Cable operators deploying PacketCable use managed IP backbones that provide service delivery consistent with that of the DOCSIS access network.
This core set of PacketCable specifications describes how to move the basic functions that are typically consolidated on a single, expensive Class 5 central office switch, onto several general-purpose servers, which leads to a low-cost, highly flexible, scalable, distributed architecture.

At a very high level, the PacketCable 1.0 architecture contains three networks: the “DOCSIS HFC Access Network,” the “Managed IP Network” and the PSTN. The Cable Modem Termination System (CMTS) provides connectivity between the “DOCSIS HFC Access Network” and the “Managed IP Network.” Both the Signaling Gateway (SG) and the Media Gateway (MG) provide connectivity between the “Managed IP Network” and the PSTN. The high-level architecture for PacketCable 1.0 with defined network elements is shown in the Figure below.



The most current version of this architecture is defined in the PacketCable 1.5 specification release. In addition to containing all the functionality of PacketCable 1.0, PacketCable 1.5 extends the PacketCable residential voice capability with new capabilities such as Fax and Modem support, analog trunking for PBXs, and SIP (Session Initiation Protocol) for session management within and among PacketCable networks.

PacketCable Multimedia
The PacketCable Multimedia initiative defines an IP-based platform for delivering QoS-enhanced multimedia services over DOCSIS® 1.1 (or greater) access networks. This platform expands on the core capabilities of PacketCable 1.0 (e.g., QoS authorization and admission control, event messages for billing and other back-office functions, and security) to support a wide range of IP-based services beyond telephony. While the PacketCable 1.0 architecture is customized for the delivery of residential telephony services, the PacketCable Multimedia architecture offers a general-purpose platform for cable operators to deliver a variety of IP-based multimedia services that require QoS treatment. For this reason, specific services are not defined or addressed in this architecture.

Although the PacketCable Multimedia platform is based upon PacketCable 1.0 concepts, the full voice infrastructure defined in PacketCable 1.0 is not a prerequisite to the deployment of multimedia services. Rather, it is intended that a particular cable operator may choose to initially deploy either voice or multimedia services, with the assurance that these platforms will seamlessly integrate and interoperate if and when they are deployed in parallel.

A high-level architecture with PacketCable Multimedia network elements is shown in the Figure below.



PacketCable 2.0
PacketCable 2.0 is a set of new specifications being developed by CableLabs, its member companies, and leading communications equipment vendors. The objective of this effort is to create an architecture that extends cable's existing Internet Protocol service environment to accelerate the convergence of voice, video, data, and mobility technologies.

The PacketCable 2.0 core service architecture is based on common standards technologies such as the Session Initiation Protocol (SIP) and the IP Multimedia System (IMS). By utilizing a common core, application servers in the network are able to deliver services to a range of clients independent of the topology of the access network. Intentionally non-service specific, PacketCable 2.0 takes a modular approach and defines the functional elements and communication interfaces necessary to support a wide array of service types.



For further information, please contact CableLabs at 303.661.9100.