CableLabs regroups for residential platform push

CableLabs regroups for residential platform push
DENVER — The melding of CableHome, PacketCable and data over cable system interface spec (Docsis) programs at CableLabs Inc. is underscoring the debate over where such functions as hardware security should reside: in a unified home router/gateway or an embedded Docsis-compatible cable modem.

Only the market can decide where the distribution and security functions for home networks should reside, CableLabs chief executive Richard Green told a specification update seminar at the Westin Hotel here last week. But, he said, home-router specialists like Linksys have shown compelling products that embed full Docsis modems within a multiport router. Now that Docsis 1.0 cable modem prices have dropped below $50, the rationale for embedding cable-modem functions within a router becomes compelling, Green said.

When Docsis launched seven years ago, specs focused on the link between the cable-modem termination system (CMTS) at the termination point of hybrid fiber/coax (HFC) networks, and the home modem interface. CableLabs added the CableHome program in the late '90s to work on issues of distributing packet services inside the home, while the PacketCable program examined converting all services, including the aggregation of traffic from many CMTS sites, to a unified Internet Protocol network.

As Docsis moved from 1.0 to 1.1, adding quality-of-service and secure authentication features, CableLabs executives realized there were growing dependencies between the client cable modem's behavior and the capabilities of the public HFC network. These dependencies will grow as CableLabs moves late this year to certify the first Docsis 2.0 modems, which use 64 quadrature-amplitude-modulation chips to provide symmetric-bandwidth services measured in tens of megabits per second.

Death of standalone

Rouzbeh Yassini, senior executive consultant to CableLabs, said the Broadband Access project links elements of PacketCable, Docsis and CableHome efforts. Broadband 1.0 will include advanced provisioning and management specs for multiple-service operators (MSOs) that allow for stronger security, end-to-end quality-of-service control and centralized support of Dynamic Host Configuration Protocol (DHCP) and Trivial File Transfer Protocol (TFTP).

Simultaneously, CableLabs has finished the specs on version 1.0 of CableHome. They have been released to developers and will be introduced for general publication April 5. The first rev will offer managed firewall services, DHCP protocols and other LAN software features. Future adjuncts to CableHome will not be numbered in a manner similar to Docsis. Instead, a CableHome-Extended spec will support in-home intercom and paging, while a CableHome-Video will add streaming video support.

The result, Yassini said, may be the death of the standalone cable modem. Already, CableLabs had helped reduce power and footprint for circuit-board manufacturers by moving to a Customer Premises Equipment (CPE)-Controlled Cable Modem, or CCCM, design in which much of the memory requirements are shared in the central CMTS by several customers. Now, OEMs can look at easily embedding a Docsis 1.1 or 2.0 cable modem inside a variety of unusual products.

"In the last round of equipment coming in for interoperability, we're not really seeing plain old standalone cable modems any more," Yassini said. "Instead, you'll see a residential gateway with modem, a phone MTA device with multiple RJ-11 hacks and a cable modem, or something that wraps up the whole enchilada of home network service."

The advantages to end users are manifold. David Fellows, chief technology officer at AT&T Broadband, said many users of Docsis 1.0 modems will not necessarily have to upgrade to 1.1 modems, if networks as a whole can handle QoS and provisioned-service constraints. If a customer wants to receive voice-over-IP support to have their multiple-service operator replace their local phone company, the customer will need a dedicated tip-and-ring device for cable packet-telephony, Fellows said. But many features can be provided through the network without customer upgrades.

Some cable-modem OEMs will offer 1.1 transitional products because of circuit-board footprint and lower power dissipation, Yassini said, while others may leap directly to 2.0. Third generation Docsis modems, based on research by Broadcom Corp. and Terayon Corp., will offer such leaps in symmetrical speeds that they will appeal to a different class of user in gaming and file-sharing and capture premium equipment and service pricing as a result. But with standard cable modems dropping well under $100, Docsis 2.0 modems are expected to quickly follow price curves down.

The focus on data-centric IP services has taken priority over the entertainment-centric OpenCable standards, though work is proceeding apace on new rights management concepts for OpenCable. The OpenCable Application Platform is in the field, Green said, and prototype televisions have been developed. On the marketing front, however, the effort is foundering on the twin shoals of slow customer acceptance of digital TVs, and the TV studios' hard-line approach to digital rights management for video content. Consequently, CableLabs is focusing much of its 2002 attention on creating end-to-end consistency between the PacketCable, CableHome and Docsis programs.

In the back of everyone's mind is the possibility of capturing most data and voice applications from residential customers, as traditional phone companies fall deeper into debt. Glenn Russell, director of the PacketCable program, said that sticking with an MSO IP infrastructure means that a user does not have to deal with the overhead of a conversion to IP from the SS7 circuit-switched backbone, or of the overhead for law-enforcement surveillance mandated under the Communications Assistance to Law Enforcement Act.

The PacketCable group is promoting a dynamic-quality-of-service bandwidth management program, in which users or MSOs can specify how much bandwidth a voice, data or gaming IP flow will receive, and can adjust the QoS in real-time. Russell predicted that with the wide proliferation of Docsis 1.1 and 2.0 cable modems in the home, the ability of MSOs to add new services in the backbone will allow them to capture new customers faster than traditional phone companies.