Almost two decades ago, widely available 500 Mbps – 1 Gbps Internet connections opened the door to services we could barely dream of. For the next step of Internet evolution, higher speeds are needed. CableLabs, the company that heads development of the DOCSIS protocol used by cable networks, already has technology that will enable home or office Internet connections at 10 Gbps, but to make them widespread this decade, it needs assistance from industry peers.
CableLabs' DOCSIS 3.1 and DOCSIS 4.0 standards already support up to 10 Gbps maximum downstream speed as well as 1 – 2 Gbps or 6 Gbps upstream speeds, respectively. To support such extreme data rates over long ranges, the technologies use the full spectrum of the cable (0 MHz to ~1.80 GHz, DOCSIS 4.0 only), 4096 quadrature amplitude modulation, narrower (25 kHz or 50 kHz wide) orthogonal frequency-division multiplexing (OFDM) sub-carriers that can be bonded inside a block spectrum, and a number of other innovations.
But while DOCSIS 3.1 is used by several cable companies in the U.S. (albeit at around 3 Gbps download speeds), DOCSIS 4.0 yet has to be widely supported. DOCSIS 4.0 is not going to become a mainstream technology overnight, there are many companies working on solutions to make 10 Gbps Internet connections a reality within this decade, reports ZDNet.
First up, to build network equipment that supports full-duplex DOCSIS 4.0 protocol, one needs appropriate modem system-on-chips. Last year Broadcom and Comcast successfully transferred data at a 4 Gbps data rate over a lab-based hybrid fiber-coaxial (HFC) network using a prototype DOCSIS 4.0 modem based on Broadcom's SoC as well as two cable modem chips and Comcast's virtual cable modem termination system (vCMTS).
Theoretically, it is possible to build a DOCSIS 4.0-supporting modem today, but the problem is that DOCSIS 4.0 requires an optical fiber network or a slightly cheaper hybrid fiber-coaxial (HFC) network or just to show its potential.
Armstrong, a U.S. cable company, launched a 10 Gbps fiber-optic network in Medina, Ohio, to deliver this extremely-fast connectivity to more than 3000 businesses and residences. Meanwhile, Charter Communications has demonstrated a higher than 8.5 Gbps downstream and 6 Gbps upstream over an existing HFC network.
Building new infrastructure takes time and money. To make it easier for operators to adopt DOCSIS 4.0, CableLabs has developed a new device called Coherent Termination Device (CTD) that teams up coherent optics and wavelength-division multiplexing (WDM) in the optical access network to increase efficiency of existing fiber optics networks and therefore increase data transfer rates. While the technology works, it is unknown how fast will it be adopted by the industry.
"While we don't know what the future holds, we do know that the internet will play a vital role in shaping it," said Phil McKinney, CableLabs president and CEO. "The 10G platform and its applications [will] create a better future for humanity."
