Cable's Fiber Outlook Gets Clearer With Coherent Optics
Just when you think that cable Internet speeds can't get any faster, along comes something to boost it higher. In cable's case, it's not only the capacity for 1 Gigabit per second now, but soon 10 Gigs and then perhaps a whopping 100 Gigs. These mind-boggling levels are being fueled by new efforts to boost capacity and efficiency in cable access networks.
The latest move is to utilize coherent optics technology in the fiber access network. Using coherent optics in long-haul transport is not new, but applying it to cable access networks is, according to a new Heavy Reading report, Heavy Reading report, "Cable's Fiber Outlook Gets Clearer with Coherent Optics."
Coherent optical transmission is a technique that provides the performance and flexibility to transport significantly more information on the same fiber. In recent years, coherent has been used by cable and telecommunications providers for long-haul communications, zipping around broadband data and video across the country or around the globe at 100 Gbit/s (100G) or more.
When applied to a cable access network, coherent will "dramatically increase capacity of the fiber access network by 10 times and will support 100 Gigabits of data per wavelength," said CableLabs, in releasing point-to-point (P2P) coherent optics specs in June.
The Heavy Reading report provides an update of cable's fiber deployments and assesses the prospects for coherent optics in cable access networks, including potential use cases and a chart of 19 technology suppliers that are participating in a CableLabs coherent optics working group.
Cable's coherent optics effort isn't intended to provide extremely high-speed Internet connections for residential users, so don't expect 100 Gigs of broadband to crash through your front door anytime soon. The initiative will produce higher performance and greater efficiency in fiber transport networks, enabling new routing scenarios at the network edge, Heavy Reading said. Coherent optics isn't so much about connectivity speeds as it is about carrying freight.
While fiber seemingly provides a limitless pathway, many cable operations are feeling a squeeze on their bandwidth. "This fiber shortage will only intensify as fiber demand for business and wireless backhaul increases and fiber deep architectures become prevalent," CableLabs said in a 2017 paper. "Efficient use of optical fiber infrastructure and adoption of innovative technology becomes critical in the evolution towards next-generation cable access networks."
Currently, applying long-haul coherent optics technologies to an access network is expensive, Heavy Reading said. The industry's goal is to produce components that cost less and have lower power requirements so that moving data, including massive amounts of TV programming and IP video, becomes more flexible and cheaper.
"Our number one goal is to reduce the cost of coherent so that it becomes an economically viable solution for access network applications," Curtis Knittle, VP, wired technologies, CableLabs told Heavy Reading. "It's really being driven by the evolution toward distributed access and the massive capacity that needs to be carried to the edge in a distributed access architecture."
As coherent optics moves further into the access arena, large cable providers, especially Comcast and Charter Communications, will have enormous nationwide networks of long-haul, metro and local access fiber capability, the report said. This will support opportunities for operators to widely distribute TV programming through video streaming, serve the needs of enterprises for high capacity and low latency, backhaul mobile traffic and prepare better for the demands of 5G, IoT, virtualization and automation.
— Craig Leddy, Contributing Analyst, Heavy Reading