Monday, May 25, 2009

ITU-T G.hn Advances on the Standards Track -- BT Joins HomeGrid Forum

The ITU-T has achieved another milestone in the progress of G.hn - the proposed unified standard that supports home networking over multiple wires (power lines, phone lines, and coaxial) -- has cleared another milestone. This month, the ITU-T progressed the new draft for G.hn and adopted as "Baseline Text" significant portions of the Data Link Layer (DLL).


The HomeGrid Forum, the trade group that promotes the G.hn standardization efforts, said that having the key elements of the DLL as Baseline Text also means that the G.hn group is on track to meet its goal of achieving Consent for the complete G.hn standard during 2009.


Stable Baseline Text for the DLL -- coupled with the December 2008 Consented Network Architecture and Physical Layer for G.hn -- further enables silicon vendors to progress their product development. To date, three silicon vendors and one silicon intellectual property vendor have announced their intention to develop products for the new G.hn standard.


Key elements of the G.hn DLL that reached Baseline Text within the ITU-T are:

  • A Time-Division Multiple Access (TDMA) Media Access Control (MAC), which provides guaranteed bandwidth and low latency for applications that have strict Quality of Service (QoS)
    requirements, such as IPTV. G.hn's MAC also includes support for multiple priority levels, to ensure that an application, such as peer-to-peer file transfers, do not impact the performance of
    higher-priority applications like IPTV, VoIP, or online gaming.


  • A Logical Link Control (LLC) sub-layer that ensures delivery of data over home electrical wiring. G.hn's LLC employs an advanced selective ARQ (Automatic Retransmission Request)
    protocol that automatically re-transmits data affected by noise and provides error-free end-to-end Ethernet services to any G.hn device on the network connected to power lines, phone lines, or
    coaxial cables.


  • A procedure for efficient aggregation of multiple Ethernet messages over a single MAC Protocol Data Unit (MPDU). This significantly increases network throughput to support applications such
    as High-Definition IPTV that have large bandwidth requirements. G.hn specifies line data rates up to 1 Gbps, significantly higher than current generation wired networking technologies.


  • State-of-the-art security based on AES (Advanced Encryption Standard - FIPS-PUB-197) and CCM (Cipher Block Chaining Message Authentication Code - NIST-SP-900-38C).


The functional areas of the DLL that are now adopted as Baseline Text ensure that G.hn can support applications with strict QoS requirements (such as high-definition video), and that G.hn can be used in
products for the service provider, consumer electronics, and PC markets.


"The United Nations' ITU-T continues to make rapid progress towards a single unified standard for delivering multimedia content around the home," said Matthew Theall, president of the HomeGrid
Forum. "Additionally, this next-generation standard has been actively driven by some of the world's leading service providers, consumer electronics manufacturers and PC companies."

In addition, the HomeGrid Forum announced that BT joined the organization and its Board of Directors.


"Today we provide customers everything from voice calling to advanced video on demand offerings. BT supports the G.hn standard as we believe it will enable us to enhance our customers' experience relating to the services
we offer - connecting customers more effectively with content," said Bob Bissell, chief customer environment strategist at BT, and HomeGrid Forum board member.
http://www.HomeGridForum.org