It used to be that, for cable operators, the letters SDV meant Some Day Vision--as in, someday we'll get around to doing that; it's in our line of sight, but we don't need to do anything so radical; leave that to the phone companies.
Of course, that's all changed as bandwidth demand and content competition drives the need for more aggressive network architectures. Now SDV means Switched Digital Video, and it's the accepted way of delivering content to a growing number of interactive subscribers, even if it sometimes conflicts with non-cable consumer electronics devices such as TiVo DVRs.
For the longest time U.S. cable operators were loath to even utter the initials SDV because they'd spent billions of dollars upgrading to HFC architectures that were supposed to be future-proof. Any hint that these networks couldn't handle the demand coming their way was tantamount to telling financial markets that they might need more money. Lately, broadband, IP video, over-the-top services and other nuances of modern entertainment and information delivery have caused MSOs to loosen up on SDV to the point of openly admitting that they're deploying the networks.
"The competitive threat determines what they're going to deploy," said Mark Dzuban, president-CEO of the SCTE, an organization charged with making certain that cable employees are as ready as their employers when it comes to new are architectural challenges.
A quick primer: In a conventional HFC system, channels are modulated at the headend and sent in bulk over fiber to a neighborhood node where they flow onto coaxial cable. As operators installed two-way communications primarily for video-on-demand (VoD) but also lately for some forms of cloud-based DVRs, they've migrated SDV to pump a batch of programming to the node, where it's stored until a subscriber requests it. As operators deliver more bandwidth-heavy content such as HDTV, SDV will let them can store greater piles in the node and selectively push down content of bandwidth-restricted coax waiting for consumers to request it.
When Time Warner Cable launched SDV in over 20 markets, including heavily trafficked Los Angeles, New York City and Dallas late last year, Kevin Leddy, TWC's executive vice president of technology said in a news release that the extra bandwidth would let the operator deliver over 100 high definition channels and launch DOCSIS 3.0 and HD video-on-demand.
"We ... know firsthand that if we want to deploy new programming options for our customers, SDV is the fastest, most cost-effective method for our existing network," Leddy said.
TWC used BigBand Networks' SDV technology. More recently, Charter Communications has linked up with Motorola to offer SDV and expand its HD programming and, according to Marwan Fawaz, the MSO's executive vice president of operations and chief technology officer, plans to have the technology installed in "more than 60 percent of our footprint by the end of 2010."
The two operators join Cox, Cablevision and others in the industry who already moved to SDV to save bandwidth. Now the rumbling has begun that the biggest of the big, Comcast, will deploy SDV this year and it's more than just to save bandwidth; it's possibly tied to the launch of IPTV. Comcast takes pride in its reputation as a technology "fast follower" so SDV has been on the back burner for years. The MSO has yet to officially launch any service (or at least to announce it) but the word is that's going to change by the end of this year.
A Comcast FCC filing said that the MSO was hoping to free up at least another 50 HD channels with SDV which it will deploy in an undisclosed number of markets with more on tap in 2011.
Does that, in turn, mean that cable operators have also changed their minds about IPTV? On the surface it might just be a matter of semantics. At The Cable Show in Los Angeles in May, a number of cable executives made it clear that the industry is, indeed, interested in IP video--but IP video isn't necessarily IPTV. Still, you say tomato, I say tomahto, and the industry's CTOs say they are looking at video over IP.
"All of us have been talking about it for quite some time," said Time Warner Cable CTO Michael LaJoie during a session at The Cable Show.
IP video, like SDV, solves pent-up consumer demand and competes with bandwidth-rich providers like Verizon's all-fiber FiOS service. An all-IP network change out won't happen overnight, but there are things happening along the way that indicate it will happen sooner rather than later, not the least of which is the pent-up demand that cable operators daily face as more IP-connected devices enter the hands of cable subscribers. More devices mean more demand, and more demand means doing something about the networks and the way that the content is delivered. That's why there's a surge of interest in SDV and why IPTV no longer scalds the tongues of those who utter it.
"This is an evolution," said Dzuban. "It makes absolute sense. The network is (eventually) going to be all IP-based and all the transport, local, regional, national are going to be IP. The cost-effectiveness in running multi-gigabit networks is just absolutely on target; it just makes sense."
But this is cable and no matter what the need, it "doesn't mean you're going to go and rip out good working gear," said Tony Werner, Comcast's CTO, speaking at that same Cable Show panel.
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