DENVER – With Gigabit Fever now sweeping the land, cable technologists are heavily focused on beefing up their broadband capabilities, both on the wireline and wireless ends.
At the SCTE Cable-Tec Expo show here last week, cable engineers stressed how they are developing, testing and deploying next-gen broadband technologies to stave off the Gigabit thrusts of Google Fiber, AT&T, CenturyLink and the like. They insisted that cable's hybrid-fibre coax (HFC) networks still have the chops to match and exceed the blazing-fast speeds that the industry's telco and ISP rivals are increasingly rolling out throughout North America with the aid of all-fibre, or at least fibre-rich, networks.
In particular, cable technologists sang the praises last week of DOCSIS 3.1, the latest version of cable's broadband spec. Designed expressly for the new gigabit era, DOCSIS 3.1 promises to let cable operators deliver downstream data speeds as high as 10 Gbps and upstream speeds of 1 Gbps or more. Drafted in record time, the spec was completed late last year and could make its debut in the U.S. and Canada as early as next summer or fall.
"The [new cable] technology is maturing and stabilizing," said John Chapman, a Canadian-born engineer who, as CTO of Cisco Systems' cable access business unit and a Cisco Fellow, is one of the industry's leaders. At most, he predicted, "we'll likely see a blending of fibre and DOCSIS technologies" over the years to come.
Jorge Salinger, VP of access architecture for Comcast, came down even stronger in DOCSIS' favor. "The apples in the tree are getting higher and higher but there's still room for growth," Salinger said, speaking at the same pre-conference symposium on DOCSIS 3.1 as Chapman. "There isn't anything we can not do with HFC networks that we can do with fibre.”
With a number of vendors showing off prototypes of DOCSIS 3.1 equipment on the exhibit floor last week, CableLabs is looking to start testing the new broadband gear for the cable industry's use sometime next spring. Senior CableLabs executives emphasized that point during multiple forums at the show. Stressing the urgency of refining and deploying cable's next-gen broadband standard, they said they plan to begin certification testing of DOCSIS 3.1 cable modems and broadband gateways in the second quarter of 2015.
Belal Hamzeh, director of network technologies for CableLabs, said the industry's R &D group is wrapping up its DOCSIS 3.1 test plans now. Those plans call for the first "plugfests" and equipment interoperability tests to start in December, followed by more formal product certifications and qualification testing in the second quarter of 2015. “So far, we are on target and the vendors are moving ahead" with products, Hamzeh said
While no DOCSIS 3.1 products have come off the assembly line yet, Salinger said that most of the prep work for the products has already been carried out. For instance, he noted, at least three major chipmakers – Broadcom, Intel and STMicroelectronics– are already building silicon for 3.1 gear.
"There hasn’t been any DOCSIS spec that was conceived and developed so fast…as DOCSIS 3.1.” – Jorge Salinger, Comcast
Salinger also stressed that the cable industry is racing the new spec to market in record time. "There hasn’t been any DOCSIS spec that was conceived and developed so fast…as DOCSIS 3.1,” he said, adding that it will take the industry even less time to start deploying DOCSIS 3.1 than it took to write the specs.
As was true for the current flagship spec, DOCSIS 3.0, the cable industry will likely roll out new 3.1 products for the downstream path sooner than products for the upstream side, the technologists said. That's in large part due to perceived consumer demand and the growing competition with such rivals as Google Fiber, which has fueled the Gigabit Cities movement.
Salinger said he expects there to be just a small price gap between the older DOCSIS 3.0 modems and the new DOCSIS 3.1 modems, which will be "backward compatible" to support both DOCSIS 3.0 and DOCSIS 3.1 spectrum. "It will be a long time before we don’t have any DOCSIS 3.0 modems in the network,” he said, noting that about half of Comcast’s deployed modems are the DOCSIS 3.0 variety, while the other half are DOCSIS 2.0. He contended that this approach will allow cable operators to seed the market with D3.1-capable modems before they have to activate DOCSIS 3.1 spectrum, enabling a smoother, more gradual upgrade of cable networks.
As DOCSIS 3.1 nears its big debut in the field, the cable industry is also looking to boost its wireless broadband capabilities. Specifically, CableLabs is now working with several different standards groups to craft specs for new products and tools designed to give cable operators and other wireless carriers the building blocks for developing and running “carrier-grade” WiFi networks.
Mike Poletti, the lead wireless architect at CableLabs, said the idea is to provide operators with the equipment, tools and software to improve the overall quality of their fledgling WiFi networks. Speaking at another pre-conference symposium, Poletti said such improvements will only become more necessary over the next few years as WiFi networks are increasingly used for a range of bandwidth-hungry applications and services.
In his presentation, Poletti cited data indicating that the number of WiFi hotspots deployed worldwide by carriers will jump from 5.2 million in 2012 to 10.5 million in 2018. In similar fashion, he said, the share of data that wireless providers offload onto WiFi networks will jump from 22% this year to 48% in 2018.
Poletti said CableLabs has been seeking to fend off this mounting challenge for several years by developing carrier WiFi requirements in tandem with the IEEE, Wi-Fi Alliance and Wireless Broadband Alliance. The various industry standards groups are teaming up to help carriers provide more consistent user experiences, better network management and integrated “end-to-end” networks.
Noting that leading groups are expected to push forward with certification testing in 2015 or 2016, Poletti argued that the vision behind Carrier WiFi “is gaining traction and becoming more and more real.” The pace of pursuit, he said, is “pretty fast for standards bodies.”
