Sure, cable will pull fiber all the way to the home or business in a targeted fashion when the need demands it, but the industry has gone to great lengths to prolong having to take that last, super-expensive step on a broad basis.
That day will come when the capacity demands and upgrade costs align, but, in the meantime, HFC's still got legs and, with apologies to ZZ Top, cable knows how to use them. Here are four ways cable is trying to save the coax (And if we missed one, don't keep it to yourself. Speak up on the message board!).
The next-gen version of Docsis aims to give cable a pipe capable of delivering max downstreams of 10Gbit/s alongside a 1Gbit/s upstream, removing the need to perform massive fiber-to-the-home upgrades. To get within reach of those numbers, Docsis 3.1 will replace 6MHz-wide channels with superwide channels made of smaller subcarriers based on orthogonal frequency-division multiplexing (OFDM) -- a technology that's done wonders for the wireless world. That will be paired with a less bandwidth-intensive Forward Error Correction scheme called low density parity-check (LDPC). Cable will need to carve out some new spectrum to accommodate 3.1 traffic, but modems will be made to work with both 3.0 and 3.1 traffic. Expect CableLabs to publish the first specs in 2013 so the vendors can get cracking on products.
EPON Protocol over Coax (EPoC)
Like Docsis 3.1, EPoC will use OFDM to get fiber-like speeds on the HFC plant. It's destined to become an Institute of Electrical and Electronics Engineers Inc. (IEEE) standard, and it will tap into the much broader EPON vendor ecosystem rather than limit itself to the smaller village of Docsis CPE, silicon and headend suppliers. And it's thinking bigger, shooting for 10Gbit/s symmetrically, rather than just in the downstream direction. There's still a debate about whether the Docsis 3.1 and EPoC projects will butt heads, though some already see EPoC as a better fit for high-end business services delivered over the HFC network.
Ethernet Over Coax (EoC)
Several cable operators are already delivering Ethernet services over Docsis to serve businesses. While most started with Ethernet-over-Docsis 2.0 to deliver a cheaper T1 equivalent, others have started using their faster Docsis 3.0 networks so they can accommodate more cloud services and applications. Though those approaches don't offer the speeds of fiber-fed MetroE services that cable's already using to deliver business-class services, the Docsis flavor does give MSOs a way to greatly expand their Ethernet-capable service footprints. And heading into 2013, keep your eye on China, which is poised to be a hotbed for EoC platforms that help operators deliver two-way voice and broadband services to residential customers and take on China's mighty telcos.
- TW Cable to Blend Ethernet With Docsis 3.0
- Comcast Meshes Ethernet With Docsis 3.0
- China Rolls Its Own Ethernet-over-Coax Standard
- Broadcom Joins China's Cable Gold Rush
Docsis Provisioning of EPON (DPoE)
This one is not a perfect fit for the list, but it is about preserving the Docsis provisioning system as operators ramp up EPON deployments for business services. CableLabs developed the specs almost two years ago, but only now are we starting to see products emerge that bring true automation to the DPoE process. After a slow start, expect DPoE to factor into cable business services strategies more prominently in 2013 and beyond.
- Bringing EPON to Cable: It's a Scale Thing
- Cable Prepares to Blend Docsis With EPON
- Docsis Gets Its EPON On
— Jeff Baumgartner, Site Editor, Light Reading Cable