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Advanced Phy, CCCMs, Home Nets on To-Do List

3/25/2001 7:00 PM Eastern

In addition to seeking third parties for Data Over Cable Service Interface Specification testing, Cable Television Laboratories Inc. has also "revitalized" its work on advanced phy and computer-controlled cable-modems (CCCMs), and is thrusting ahead on home networking standards.

An enhancement to the DOCSIS 1.1 spec, advanced phy is expected to dilate the extremely noisy and svelte return path on cable broadband networks by allowing more bits per hertz to flow upstream. It's been argued that such nascent applications as video conferencing and peer-to-peer applications will require a wider return path.

Already, some cable operators have noted trends which indicate that cable-modem customers are more frequently clogging up the return path by sending excessively large audio and video files via electronic mail. As the gap between downstream and upstream usage ratios narrows, operators expect that they'll need to build a more symmetrical pipe to handle growing two-way traffic loads.

Charter Communications Inc., which offers tiered high-speed services and manages bandwidth usage closely, is beginning to see upload and download traffic approach symmetry among "power users," said MSO director of high-speed data Arnie Taylor.

For example, the heaviest user on a particular system downloaded 18 million packets, but sent 10 million packets upstream. Meanwhile, another heavy bandwidth user downloaded 8 million packets and uploaded 7 million packets-close to a 1:1 ratio.

Though Charter presently caps how much data can be sent upstream, a video equivalent to Napster Inc.'s audio file-sharing software would definitely call for operators to beef up the return path, Troy said.

CableLabs executive consultant Rouzbeh Yassini said an advanced phy specification should be completed by the third quarter of this year.

One company with a big stake in CableLabs' advanced phy work is Terayon Communications Systems Inc. The company has pushed its proprietary modulation scheme, S-CDMA (synchronous code vision multiple access), as an advanced phy option for several years.

Terayon has already submitted an S-CDMA-based cable-modem termination system and cable modem to CableLabs for consideration as it plans the spec. The company also entered an S-CDMA cable modem for CableLabs' current certification wave.

A Terayon spokesman acknowledged the chances of the product getting the DOCSIS seal in wave 17 are slim. The company is merely "kicking the tires" at this point, he noted.

Terayon isn't the only vendor bringing advanced phy proposals to the table. Broadcom Corp., Texas Instruments Inc. and Conexant Systems Inc. are developing a similar modem based on the open TDMA (time-division multiple access) standard.

Linked to advanced phy is the CCCM, a more extreme version of the internal PCI (peripheral-component interface) cable modem.

Zoom Telephonics Inc. and GVC Corp. have DOCSIS 1.0-certified PCIs based on Conexant's reference design.

As an incremental step beyond the cable modem PCI, the CCCM will be designed to share resources such as processing and power with the PC or set-top that encases it, and to remove the need for a second Ethernet card.

That will reduce the cost of cable modems considerably. While the price of today's stand-alone cable modems has dropped to roughly $99, a CCCM is expected to run about $50, a price tag that PC manufacturers such as Gateway Inc., Dell Computer Corp. and Compaq Computer Corp. could easily swallow.

Yassini predicted the CCCM could have a profound impact on the OEM sector and drive consumer adoption of cable-modem technology. He said CCCM interops are expected to begin in the second quarter of this year, followed by product certifications in 2002.

Though the PCI market has yet to take off, Broadcom-which has its own version of an internal cable modem-will participate in the CCCM process, said Rich Nelson, director of marketing for the company's broadband communications unit.

Motorola Broadband Communications Sector, the largest maker of DOCSIS modems, is another player eyeing the technology. The company's PCI model, the "SurfBoard-4000," is presently in testing at CableLabs.

The SB-4000 costs from $100 to $110 per unit, though large volume orders would reduce that price tag, said John Burke, vice president and general manager of Motorola Broadband's cable modem division.

INTEL: WAIT AND SEE

"We believe there are some strong merits to (the CCCM), so we're giving it as much diligence as we can," he added.

While some of the larger cable modem players are plotting CCCM plans, others are taking on a wait-and-see attitude.

For example, Intel Corp., which had demonstrated CCCMs as recently as last year's Western Show, doesn't have any product plans yet, said spokesman Tom Potts.

"That could change if there's interest in this product. We're gauging how the market will accept them," Potts said.

Add HighSpeed Surfing Inc. to that boat. HSS spokesman David Fox said the company is not building a CCCM product today, but wouldn't rule out that possibility in the future.

For now, HSS will continue to focus heavily on wireless cable modems based on home networking protocols such as 802.11.

While advanced phy and CCCMs are squarely on CableLabs' short-term agenda, home networking is also an area the organization is exploring with vigor.

Though still new in the eyes of consumers, the home-networking concept is beginning to gain in mind share and shelf space, said Glenn Edens, president of AT&T Strategic Ventures and vice president of broadband technology at AT&T Labs.

Edens pointed to a recent "watershed event" to prove his point. Fry's Electronics Inc., a consumer-electronics chain, has started to dedicate an aisle to home-networking products.

As home networking quickly establishes momentum, that train will leave the station with or without cable-industry input.

Cable plans to get on board with CableHome, a CableLabs initiative launched early last year. Today, CableHome's goal is to deliver services across home networks and devices over the operator's broadband infrastructure, explained Edens, who has taken a prominent role in the project.

As it does with DOCSIS, CableLabs plans to build specification and certification processes aimed to ensure that home networking gear interoperates with DOCSIS and PacketCable-based networks, added CableLabs CTO David Reed.

Presently, CableLabs is drafting an initial "Home Networking Architecture Report," which will identify interfaces of the CableHome architecture, Reed added.

To that end, CableHome will center efforts on quality of service, a vitally important element if consumers plan to send video and voice packets to Web pads and personal digital assistants. Without QoS, those packets could be delayed or lost on their way to the end device.

Because home networking still is in its infancy, CableHome also is sifting through a throng of wired and wireless protocols, including HomePNA, HomeRF, Bluetooth, 802.11 and HomePlug, a platform that taps into existing electrical lines to distribute high-speed data.

It's still too early in the game to declare which protocols will win out with consumers and equipment vendors, Edens said.

On the high-speed wireless front, 802.11 has a marked lead on its platform rival, HomeRF.

A move by Intel last week only compounded that notion. Intel said its next-generation "AnyPoint" wireless home-networking product line will use the 802.11b standard, which touts speeds of 11 megabits per second. The company's initial product release uses the first iteration of HomeRF, which bridges slower 1.6 mbps throughputs.

BLOW TO STANDARD

Potts said Intel will continue to manufacture and sell its existing HomeRF products as a "low-cost" solution-at less than $50 per node-but will add 802.11b to the AnyPoint line by the third quarter of this year.

"For us to continue to be good competitors in this market, we thought we needed these high-speed products by this summer," Potts said, adding that there's uncertainty about whether HomeRF's faster 2.0 spec will be ready by that time.

Intel's defection will damage HomeRF's chances of becoming the dominant wireless standard for home networking, even as its 10 mbps platform is under development, said Navin Sabharwal, vice president of residential and networking technologies at research firm Allied Business Intelligence Inc.

Sabharwal said HomeRF, which does a good job handling QoS for low-latency applications like voice and video streaming, can improve its chances if it finds a way to boost its retail position and gain new, high-profile consumer electronics and silicon backers within the next six to nine months. Motorola Inc., Compaq Computer Corp., Siemens Information and Communications Mobile Group and Proxim Inc. are among HomeRF's key members.

"Ultimately, this is a momentum game," he said. "If they lose Intel, HomeRF will need to deliver 2.0 on time and get into consumer faces with products."

Despite home networking's growing popularity, it's not likely to develop into a mass-market technology like digital video, Edens predicted. Still, he said, cable operators will someday offer such services at rates between 20 to 30 mbps.

CableHome will eventually have a say in how that bandwidth is distributed throughout the home. Industry observers have predicted a "residential gateway" will become that conduit.

The shape of the gateway in the cable sphere is largely undetermined. Set-top and cable-modem vendors already have started to spin their advance products in that vein.

In Eden's personal opinion, the set-top box is not the most ideal gateway, because consumers tend to move it and unplug it, at times unnecessarily. Instead, Edens said he prefers the cablemodem gateway model.

Convenience will also play a part in how consumers adopt the technology.

"If you can make it easy, consumers will want to consume it," Edens said, noting that home networking installation services could become a "thriving businesses" for cable operators.

September