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Question 4/15

Question 4/15 - Broadband access over metallic conductors
(Continuation of Question 4a/15)
The continuing customer demand for ever higher bit rate data services, high-speed Internet access and other innovative services, and the on-going needs of network operators to fully exploit their installed base of copper cables, will require the development of new Recommendations and enhancements to existing Recommendations covering all aspects of Transceivers operating over metallic conductors in the access part of the network. These studies will include, but are not limited to, the transport of higher layer protocols, the management and test of the access systems, spectral management aspects and energy saving techniques. will raise the bar to 1 Gbit/s by combining the best aspects of optical networks and DSL in hybrid systems with a total wire length to the customers’ transceiver up to 250 m.
The following major Recommendations, in force at the time of approval of this Question, fall under its responsibility: G.991.x series, G.992.x series, G.993.x series, G.994.1, G.996.x series, G.997.1, G.998.x series, G.999.1.
The target audience for this question are the technology suppliers, chipset vendors, equipment vendors, and service providers active in the domain of providing access to a high-speed network from the premises. A global audience is targeted to facilitate a unified approach to the broadband access over metallic conductors.
What enhancements are needed to the G.99x series of Recommendations:
  • in the light of design, network deployment experience, and evolving service requirements?
  • to optimise the transport of IP-based services?
  • to optimize bit rates achieved by means of vectored groups of pairs ?
What new Recommendations are needed:
  • for transceivers for customer access over metallic conductors?
  • to carry out line testing?
  • to enable higher bit rates to be achieved by means of e.g, pair bonding or coordination and/or vectoring over a group of pairs?
  • to enable transport of higher layer protocols ?
  • to optimize the quality-of-experience to the end user ?
What enhancements to existing Recommendations are required to provide energy savings directly or indirectly in Information and Communication Technologies (ICTs) or in other industries?
What enhancements to developing or new Recommendations are required to provide such energy savings?
Study items include, but are not limited to:
  • Modulation and transport techniques, tools for spectrum management (including dynamic spectrum management), real noise environments, handshaking procedures, testing procedures, physical layer management procedures, energy saving techniques.
  • Techniques for coordination of the transceivers in a group of pairs as to operate within given limitations, e.g, limitations related to aggregate energy usage or aggregate data rate.
  • Techniques for transport of time and synchronization over the copper access network, in collaboration with Q13/15.
  • Coordination within the digital access section between optical access and copper access to minimize complexity and optimize QoS.
  • These studies should take account of the different regulatory environments around the world.
  • Transceiver to higher layer inter-connection techniques
These studies will include any specific requirements:
  • to optimise the transport of IP-based services
  • to optimise the transport of Ethernet based services
  • to support the management of access systems operating over metallic conductors
Tasks include, but are not limited to:
Maintenance and enhancements of existing Recommendations and production of new Recommendations in the G.99x series.
NOTE: An up-to-date status of work under this Question is contained in the SG15 Work Programme at:
  • G.991.x series, G.992.x series, G.993.x series, G.994.1, G.996.x series, G.997.1, G.998.x series, G.999.1.
  • Q1/15, Q2/15, Q4/15, Q18/15, Q13/15.
Study Groups:
  • ITU-R SG1 and SG5
  • ITU-T SG5 on EMC and various copper cable topics
  • ITU-T SG16 on multimedia aspects
Standardisation bodies, forums and consortia:
  • ATIS Committee COAST and its subcommittee on Network Access Interfaces (NAI)
  • ATIS Committee STEP and its subcommittee on Telecom Energy Efficiency (TEE)
  • CCSA on xDSL related topics
  • Broadband Forum on Test methodology, performance, and transceiver interfacing with higher layers.
  • ETSI EE on DSL energy efficiency
  • ETSI ATTM TM6 on xDSL related topics
  • ETSI PLT on spectral interference from power line communication
  • HGI on residential gateway
  • IEC CISPR I on EMC requirements
  • IEEE on Ethernet and communication
  • IETF on xDSL MIBs
  • TIA TR-41 on Spectral management considerations
  • TTA on xDSL related topics
  • TTC on xDSL related topics
  • TMForum on access systems management solutions