The first wave of cable’s next-generation cable modems, which promise downloads up to 160 megabits per second, are currently in the middle of certification testing by CableLabs and should be ready for early deployments in 2008.
But as the ship dates near for the initial modems that use CableLabs’ Data Over Cable Service Interface Specification 3.0, it’s becoming clearer that DOCSIS 3.0 modems will be more expensive than perhaps previously anticipated.
John Sweeney, Scientific Atlanta director of product strategy and management, estimated that the street price of a 3.0 modem will be around $100, adding that quantity has a large effect on the per-unit price. Current DOCSIS 2.0 modems cost an average of $65 to $70, according to research firm In-Stat.
“It’s not the $10-to-$20 delta [between 2.0 and 3.0] the cable operators were encouraging the industry to hit,” Sweeney said.
DOCSIS 3.0 delivers higher bandwidth by virtually combining several 6-Megahertz channels in a digital cable system, to act as if they were one. The specification requires cable modems to support four downstream and four upstream channels, theoretically capable of sending data at around 160 Mbps down and 120 Mbps up.
One of the reasons DOCSIS 3.0 modems cost more is that to be able to bond four channels up and down, they require much more memory than their 2.0 cousins. For example, while a 2.0 modem may have needed 8 megabytes of memory, a 3.0 unit will require upward of 32 MB.
As Sweeney explained: “You have to park the packets in memory and then reassemble them. In the data rates we’re working with -- 160 megabits per second -- that’s a lot of bits you have to reassemble.”
Over time, vendors will optimize modems so that future models should have lower memory requirements, said Peter Percosan, executive director of broadband strategy for Texas Instruments’ residential gateway business. TI is supplying DOCSIS 3.0 chips to Arris, Scientific Atlanta and Motorola, among other vendors.
“The initial focus [for DOCSIS 3.0] was functionality and stability,” he said. “There’s a lot of opportunity to shrink the memory footprint.”
Mike Paxton, an analyst with research firm In-Stat, said cable modem suppliers are anticipating that volume shipments of 3.0 units will begin in September or October 2008. (In-Stat is owned by Reed Business, publisher of Multichannel News.)
That’s about a quarter later than many previously expected, but he said such slippage is “common enough when you’re talking about a new technology like this,” he said.
“I don’t see anything over all with red flags in terms of rolling out the products,” Paxton said. “But maybe there was a little bit too much enthusiasm about how quickly this would happen.”
CableLabs was scheduled to complete certification testing of the first wave of DOCSIS 3.0 this week. Vendors that have submitted cable modem and CMTS products for the tests include Arris, Cisco, Motorola and Scientific Atlanta.
After testing is completed, a certification board comprised of cable operator executives reviews the results and issues recommendations on whether individual cable modems or CMTSs comply with the specification. The certification board, which was scheduled to meet Dec. 4 to review results of the DOCSIS 3.0 testing, may request that a product undergo additional retesting after a vendor addresses any issues.
That means CableLabs-certified DOCSIS 3.0 products may be ready as early as January, or it could be a few months longer than that.
“DOCSIS specifications are complicated, and sometimes it takes more than once to get through certification ... Early specs can be read differently,” said Tom Cloonan, chief technology officer for Arris’s broadband division. “We’re hopeful [about receiving certification], but we’re realistic.”
Sweeney said Scientific Atlanta is in “a ramp-up mode” to produce its first DOCSIS 3.0 modems, with the initial models expected to roll off the production line in the early first quarter of 2008.
“The big issue will be getting orders in place to justify production,” he said. The question will be how long it will take MSOs to evaluate the new products in their labs, a process he said could take up a good part of the first quarter.
Rouzbeh Yassini, an early cable-modem pioneer who is CEO of venture-capital firm YAS Broadband Ventures, believes operators won’t begin wide commercial deployments of DOCSIS 3.0 until mid-2009 at the earliest.
Historically, he said, for a new cable technology, it has taken about 18 months to go from factory production to field implementation. “If you can do it more quickly, more power to you,” he said.
“Cable operators have to keep making money and they’re going to continue deploying what works,” Yassini added, meaning current-generation DOCSIS 2.0 cable modems.