How cable will hit gigabit speeds and create a tricky business problem in the process

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The Cable Show began on Monday, and as the industry executives gathered in Washington D.C. they faced two big threats to their core lines of business. One involves the nature of pay television in an age of over-the-top content, and the other, the rise of gigabit networks.

In many ways it would seem that the rise of gigabit networks would crush the business of providing pay TV, but in fact, if cable companies play it smart, they may find a way to walk the line as their industry transitions to all-IP content delivery over broadband networks. They may even find new sources of revenue by offering IP services such as home security and automation. To understand what cable firms are dealing with, I spoke with Phil McKinney, the president of CableLabs, the industry standards setting body that is responsible for pushing cable’s access technologies.

CableLabs is the organization behind the DOCSIS 3.0 standard, which has helped cable companies roll out 100 Mbps and faster speeds. Unfortunately, those speeds have a practical limit that won’t help cable providers like Comcast or Time *****W Cable compete with Google’s gigabit networks. And if AT&T or municipalities get aggressive about deploying such networks, cable providers might find themselves selling the equivalent of feature phones in a smartphone world.

Getting cable to a gig

Enter DOCSIS 3.1, the next generation of the cable access technologies. The new standard will allow cable firms deploying D3.1 equipment to deliver up to 10 gigabits per second down and 1 gigabit up. The technology uses OFDM technologies familiar to the wireless industry to cram more bits into a single megahertz of available spectrum used in the cable plants (it’s 11 bits per hertz if you care). Thus, cable providers can then deliver more bandwidth using their existing radio frequencies.

These RF channels are part of cable’s legacy of delivering analog television signals over coaxial cable. In today’s hybrid fiber and coax networks some of the overall transmission is digital, but the coaxial and RF frequency limits remain in some parts of the network.

Cable firms still haven’t gone all-IP, which means that most cable companies are dedicating some of their spectrum to their pay television business and some to delivering broadband. One technology uses IP and the other uses QAMs. But as people demand more bandwidth and higher definition TV channels, cable operators must decide where to allocate their limited spectrum, or lose market share they have gained in the broadband market.

McKinney is also touting new compression codecs like HEVC that help lower the number of bits in a stream but still deliver high-definition quality. It uses half the information that MPEG-4, the current standard, uses. That gives cable companies a little more room on their spectrum to allocate for more broadband channels or more TV channels. McKinney notes that CableLabs is moving faster than it has ever moved in order to get DOCSIS 3.1 out to constituents — achieving in two and half years what it took five to do for previous standards. Comcast says it expects to start deploying DOCSIS 3.1 in 2015.