CableLabs Finish Spec for Symmetric 10Gbps DOCSIS 3.1 Cable Broadband

The dream of 10Gbps (Gigabits per second) capable Full Duplex DOCSIS 3.1 technology, which could one day be deployed on Hybrid Fibre Coax (HFC) based cable networks like Virgin Media, has taken another step forward after CableLabs completed the technology’s official specification.

At present Virgin Media’s network in the United Kingdom is predominantly based off the older EuroDOCSIS 3 (Data Over Cable Service Interface Specification) technology, which is a variant of the DOCSIS 3.0 cable standard that has been adapted to EU frequency allocations and permits more bandwidth for the downstream data path.

The top download speed that Virgin offers to consumers over their current UK network is 350Mbps (20Mbps upload), although they could push this quite a bit further if they wanted (500Mbps might be the next upgrade). In the very near future we also expect Virgin and other cable operators to adopt the latest DOCSIS 3.1 standard, which can in theory deliver peak network speeds of 10Gbps download and 1Gbps upload (end-users won’t get this top speed).

However for a long time the holy grail of HFC networks has been to achieve a Full Duplex transmission via DOCSIS 3.1 (i.e. 10Gbps for both upload and download), which enables upstream and downstream traffic to efficiently use the same spectrum at the same time. A lot of work has gone into designing this (here and here) and now the first specification has finally been completed.

However consumers don’t need multi-Gigabit speeds just yet and that’s lucky because Full Duplex DOCSIS 3.1 would not be an easy beast to deploy in the United Kingdom, which is due to its stiff power requirements and the need for a deeper roll-out of fibre optic infrastructure into the HFC network (i.e. we won’t see it in the UK for a long time).

Mind you we haven’t even seen DOCSIS 3.1 yet, let alone the new Full Duplex version, but it shows that there’s plenty more performance to come.

Phil McKinney, President and CEO of CableLabs, said:

“In the United States, more than 90 percent of households are connected to an HFC (hybrid fiber-coaxial) network, and consumers typically have higher download speeds than upload speeds. By enabling Full Duplex DOCSIS, the upstream and downstream traffic can flow at up to 10 Gigabits concurrently, doubling the efficiency of spectrum use.”

In the meantime the wait for Virgin Media to start customer trials of ordinary DOCSIS 3.1 continues. A big chunk of the operator’s network is technically prepared for it and the first viable router kit is now in the market (e.g. ARRIS’s TG3442 cable router – a possible SuperHub / Hub 4.0 contender), although so far they’ve been reluctant to confirm any solid plans.

Part of the reason for the gradual pace of progress towards DOCSIS 3.1 is because the operator remains focused on their £3bn Project Lightning network expansion, which aims to reach 4 million extra UK premises by the end of 2019. On top of that there’s still room for extracting more speed via EuroDOCSIS 3.0 and Virgin will also want to ensure that they have the right capacity in place before rolling to 3.1.

However the expected growth of 1Gbps capable FTTP/H networks in the UK may provide Virgin Media with some encouragement to get moving, eventually.