After talking about it for more than two years, Harmonic Inc. (Nasdaq: HLIT) has finally launched a super-dense edge QAM that's expected to factor in at Comcast Corp. (Nasdaq: CMCSA, CMCSK) as that operator beefs up streaming capacity for video-on-demand (VoD) and switched digital video (SDV). (See Comcast Getting Ready to Uncork SDV.)

Harmonic's latest entry, the "HectoQAM," aims to set the bar on density with 648 QAMs or as many as 36 QAMs per port, numbers that, the company believes, will be needed as demand for cable unicast and multicast video streaming services (SDV, VoD, and IPTV) increases and the amount of available headend space remains relatively constant. (See Harmonic Unleashes 'HectoQAM' .)

The HectoQAM (also called the NSG 9000-40G) fits inside the same physical two-rack unit profile of the company's previous top shelf edge QAM, the NSG 9000, but packs in more than four times the capacity. The current iteration of the NSG 9000, by comparison, supports 144 QAMs. On the competitive front, the HectoQAM unseats the 576 QAMs offered by the LiquidxStream Systems Inc. LxS-3616 edge QAM. However, both of those products claim to support a maximum of 36 QAM channels per port.

That added density should come in handy as MSOs are forced to deploy more QAM capacity. A typical VoD deployment requires about four to six QAMs, and perhaps 16 QAMs per user group for SDV. That number's expected to jump to 24 or more based on anticipated trends, according to Yoav Derazon, Harmonic's senior manager of cable solutions and strategy.

And MSOs should be pleased with the effect those densities will have on QAM channel pricing. Harmonic believes the average cost will reach below $100 per channel threshold for anything that requires eight QAMs per port. That's the game-changing price Time Warner Cable Inc. (NYSE: TWC) is believed to be paying Arris Group Inc. (Nasdaq: ARRS) and LiquidxStream for a recent edge QAM business award. (See Arris Wins at Time Warner Cable .)

The HectoQAM is considered "universal" in the sense that it can share capacity among different applications. The initial product will target VoD and SDV, but Harmonic expects to add in support for Docsis 3.0 twelve to 18 months from now. It's also designed to work as the downstream component of "modular" cable modem termination system (CMTS) architectures.

The new gear supports 40 Gbit/s of input by multiplexing four 10GigE interfaces, up from the 6-Gbit/s processing core of the NSG 9000. The previous platform had enough for most SDV multicast needs, but Harmonic thinks the added punch will come in handy as the demand for unicast services such as cable VoD and IPTV increases.

Harmonic is teaming the HectoQAM with virtualization software that enables the cable operator to break down the device's 648 QAMs into smaller groupings, important because some backoffice systems are only capable of managing up to 24 QAMs per device.

The HectoQAM also looks like a precursor to the edge QAM piece of the Converged Multiservice Access Platform (CMAP), a product being specified by Comcast that will combine edge QAM and CMTS functions and take density to the next level. The CMAP is also expected to help cable operators migrate video services to IP. (See Comcast Proposes Its God Box and More MSOs Back Comcast's Big Box Project .)

Although CMAP specs are already calling for densities greater than the first iteration of the Harmonic's HectoQAM, the vendor thinks it has the baseline to ramp up when needed. "It's really an evolution using the same technology," says Gil Katz, Harmonic's senior director of cable solutions and strategy.

"No one needs 100 QAMs per port yet, but this [HectoQAM] technology will allow that," he says. "We're coming with 36 [QAMs per port] because it's what the market needs today. We could easily go beyond 100 QAMs per port."

Harmonic believes it has a 12-to-18 month jump on its competition when it comes to density, a situation that will make it difficult for rivals to keep up on pricing.

Heavy Reading senior analyst Alan Breznick says the HectoQAM "does seem to put Harmonic in the front right now. But you can be sure that someone's going to be gunning for them now."

Based on company data, here's how the HectoQAM and some competing products, including chassis-based gear, stack up from a density standpoint:

Table 1:

Harmonic will start shipping the HectoQAM by September. Among MSOs, Comcast has already selected edge QAMs for SDV from Harmonic, Arris, and Motorola Inc. (NYSE: MOT).

— Jeff Baumgartner, Site Editor, Light Reading Cable