C-Docsis, as it's called, is one of three access technologies selected earlier this year by the State Administration of Radio, Film and Television (SARFT) as an acceptable cable access standard for a next-generation broadband (NGB) project that will help the country's cable operators overhaul their plant for triple-play services and arm them to compete against China's powerful telcos, such as China Telecom Corp. Ltd. (NYSE: CHA), China Unicom Ltd. (NYSE: CHU) and China Mobile Ltd. (NYSE: CHL) (See Broadcom Helps Tweak Docsis for China.)
China's NGB initiative is expected to produce nearly 200 billion yuan (US$32 billion) in infrastructure investment over the next five years, according to BDA Research. It's also expected to help pave the way for some consolidation and organization of China's 2,000-plus cable MSOs, many of which are run by municipalities, with many currently offering only basic video services for a few dollars a month over antiquated plant.
SARFT, essentially the Federal Communications Commission (FCC) of China, has standardized on two other Ethernet-over-coax (EoC) technologies for NGB: HiNOC, a baseband technology that may ultimately merge with Multimedia over Coax Alliance (MoCA) , and a modified version of HomePlug A/V. SARFT is expected to let those three technologies duke it out for market dominance. (Light Reading Cable will discuss the other cable NGB options for China in a future story.)
As C-Docsis goes, Broadcom is in the pole position, as it is (so far) the sole supplier of silicon for the necessary network-side gear.
What is C-Docsis?
A key goal of C-Docsis is to make Docsis technology cost-competitive in markets that teem with high-density apartments and other multiple-dwelling units (MDUs). Many Chinese cable systems are considered "fiber deep" because they run PON to the MDU before handing things over to the building's coax network that, in turns, transports services to the individual residences. Traditional Docsis cable modem termination systems (CMTSs) aren't cost-competitive in those environments because they are made to serve tens of thousands of customers, rather than just a couple hundred.
C-Docsis enables any Docsis 2.0- or Docsis 3.0-certified cable modem or set-top with an integrated Docsis Set-Top Gateway (DSG) to interoperate with what's essentially a stripped-down cable modem termination system (CMTS), explains Ernie Bahm, senior director of marketing for Broadcom's Broadband Communications Group. But in C-Docsis parlance, this component is called the Coax Media Converter (CMC).
The CMC functions like a CMTS but does not support the core routing functions. The CMC receives the the PON protocol or point-to-point Ethernet signal and turns it into Docsis packets that can be sent along the coax to the cable modems.
"It's the same technology, but uses a different architecture," Bahm says.