While DOCSIS 3.0 still has a lot of legs left when it comes to increasing the capacity on the upstream over the next few years, it's never too early to plan for the next phase.
During a session, Cox's Jeff Finkelstein, senior director of network architecture, said the dynamics have changed on the consumer side, which is placing a bigger burden on the upstream return path.
"There has been a quantum change in how content is consumed," Finkelstein said during his "Upstream bandwidth futures" presentation. "It's any content, anywhere, anytime, any device, so it has changed the way that content is looked at from a consumer perspective and from a producer perspective. The amount of time it takes to plan for this kind of change grows exponentially."
Finkelstein gave attendees a rundown of how to increase upstream capacity, including the tradeoffs associated with low-splits, mid-splits, high-splits and top-splits. Cable operators can also improve their upstream capacity through tried-and-true methods such as adding upstream channels, higher order modulation, segmentation and node splits, but he cautioned that cable operators need to be planning their future implementations now.
Jorge Salinger, Comcast's vice president of access architecture, outlined the converged multiservice access platform (CMAP) that includes collapsing edge QAMs into cable modem termination systems for increased density. Salinger said the cable industry needs to implement CMAP in order to keep up with the demand for cable's narrowcast services.
CMAP also seeks to use less power and space than current implementations. CMAP equipment will feature roughly 50 percent space savings in the same headend and more than 50 percent in power savings.
"One of the major points of this is let's get something that is space-efficient, power-efficient, because we don't have the room to double or quadruple our CMTSs," Salinger said.
CMAP also provides for PON deployments, which Salinger said would be used for commercial services, IP video and future access technologies.
Comcast first conceived the CMAP concept in 2008, followed by the start of specification development last year. Working with vendors, cable operators and advisors such as CableLabs and Cable Europe Labs, specification development was divided up into three phases.
In March of this year, the first version of the hardware and functions specification was completed, followed by a revision in July. Also in July, the first versions of the configuration and management and modular interface specifications were completed. The second and final iterations of the modular access shelf-to-packet shelf interface (PASI) and configuration and management specifications, along with the third version of hardware and functions, will be wrapped up next month.
Testing of CMAP equipment could start next year, followed by more product availability in 2012 and deployments in early 2013.