ITU members last week gave final approval to G.fast, the new ITU broadband standard designed to deliver access speeds of up to 1Gbit/s over existing telephone wires.
The approval of the the physical-layer protocol aspects of G.fast – defined by Recommendation ITU-T G.9701 ‘Fast Access to Subscriber Terminals (FAST) - Physical layer specification’ – follows the approval in April this year of ITU-T G.9700, a companion text specifying methods to ensure that G.fast equipment will not interfere with broadcast services such as FM radio.
G.fast is designed to be used within the fibre to the distribution point (FTTdp) architecture, combining the best aspects of fibre and DSL. Within 400 metres of a distribution point, G.fast provides fibre-like speeds matched with the customer self-installation of DSL, resulting in cost-savings for service providers and improved customer experience. Not only does this reduce costs but it also paves the way for next generation broadband services such as Ultra-HD ‘4k’ or ‘8k’ streaming.
Dr Hamadoun I Touré, Secretary-General of ITU said: ‘The time from G.fast’s approval to its implementation looks set to be the fastest of any access technology in recent memory. A range of vendors has begun shipping G.fast silicon and equipment, and service providers’ lab and field trials are well underway.’
This technology is complementary to existing FTTH strategies, particularly in scenarios where G.fast proves the more cost-efficient strategy to laying fibre right to the doors of customer preimses.
G.fast’s ‘zero touch’ operations, administration and management will increase the speed of new-service rollouts. This remote management of user connections will simplify migrations to G.fast, and the standard’s coexistence with VDSL2 offers service providers the agility required to switch customers between G.fast and VDSL2 as business operations demand.
The development of G.fast has been coordinated with the Broadband Forum’s FTTdp system architecture project. ITU and the Broadband Forum have been working in collaboration to ensure that G.fast solutions can be quickly placed into FTTdp deployments.
Robin Mersh, CEO of the Broadband Forum said: ‘The Broadband Forum is working closely with the ITU to ensure compliance with the G.fast standard and certify chipsets and equipment. We have already set our first plugfest for January 2015.’
The Broadband Forum has begun developing a test suite and certification programme for G.fast systems. The test suite will provide for interoperability, functional and performance testing. A beta-trial of the certification programme is planned for mid-2015, and certified G.fast implementations are expected to appear on the market before the end of 2015.
However G.fast still has the potential to deliver even more performance and an extended set of features which are being developed by the ITU-T Study Group 15. The work will focus on targeting performance enhancements which will include additions to its range of low-power states. These features are likely to be available for incorporation into service providers’ G.fast deployments as early as 3 July 2015.
