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Question 9/15

Question 9/15 - Transport network protection/restoration
(Continuation of part of Question 9/15)
The explosive growth of the Internet, standardisation of 40 and 100Gbit/s Ethernet, anticipated standardisation of Ethernet rates greater than 100 Gbit/s, and other packet based traffic are the key drivers for the development of new network protection and restoration related standards. In addition, the development of the Optical Transport Network (OTN) provides the ability to dramatically increase the bandwidth, and thus traffic carrying capacity, of optical networks. The emergence of packet transport mechanisms has also motivated the need for multi-layer survivability mechanisms.  In order to ensure these new transport networks achieve carrier-class performance, it is essential that the network protection/restoration techniques continue to evolve and relevant Recommendations are updated.
Responsibilities under this Question include the following areas of standardization related to these new technologies:
  • Specification of all protection switching processes related to the OTN and SDH layer networks
  • Specification of protection switching processes for transport of data/packet traffic (e.g., IP, ATM, MPLS, MPLS-TP, Ethernet, other packet-based transport technologies, Storage Area Networks (SAN)) via transport networks
  • Specification of survivability capabilities and development of a strategy for multi-layer survivability interactions (including those where different transport technologies are used at different layers)
Recommendations related to transport technologies (e.g., SDH, PDH, OTN, MPLS-TP, Ethernet and other packet-based transport technologies) used in the access environment and not covered by other Questions of ITU-T SG15, such as Flexible Multiplexers, are also covered by this Question. The following major Recommendations, in force at the time of approval of this Question, fall under its responsibility: G.841, G.842, G.808.1, G.873.1, G.873.2, G.8031, G.8032, G.8131, I.630 and Y.1720.
What additional protection/restoration mechanisms for transport equipment should be recommended to provide enhanced survivability capabilities and a cohesive strategy for multi-layer survivability interactions?
Study items to be considered include, but are not limited to:
  • Network protection/restoration Recommendations to provide enhanced survivability capabilities and a cohesive strategy for multi-layer survivability interactions. This includes revisions to Recommendations G.841, G.842, G.808.x, G.873.x, I.630, G.8031/Y.1342, G.8032/Y.1344, G.8131/Y.1382 and Y.1720. These Recommendations cover SDH, OTN, ATM, MPLS, MPLS-TP and Ethernet layer protection, as well as multi-layer survivability, including interactions with protection at data/packet layers
  • Ring protection mechanisms for OTN and packet transport networks including Ethernet Enhancements required to the network maintenance  protection/restoration Recommendations in order to meet the needs of:
    • the access network
    • the NGN and transport of Internet and other packet based traffic.
  • Clarification and resolution of technical issues in published and draft
Tasks include, but are not limited to:
  • Complete Recommendation G.808.2 (ex G.gps-2)
  • Complete Recommendation G.smp (shared mesh protection) and associated technology-specific shared mesh protection mechanisms
  • Enhancements to Recommendation G.873.2 (ex G.otnprot-2)
  • Enhancements to OTN protection mechanisms, for example nested protection schemes and M:N ODUk SNC
  • Enhancement to Recommendations for other survivability techniques including per packet priority-based protection switching for packet based transport networks
  • Enhancement and improvement of linear and ring protection switching Recommendations for OTN and packet-based technologies
  • Clarification of relationships between protection switching and restoration technologies
  • Clarification of relationships between survivability function of a packet-based transport and survivability function in other layers or other transport technologies (e.g., SDH, OTN, etc.)
  • Clarification of  interworking between different protection schemes within a layer network (e.g. interworking linear and ring protection)
  • Enhancement to relevant Recommendations to include protection/restoration of services that use broadcast and multicast functionality
  • Enhancement to relevant Recommendations to include partial protection switching in rooted multipoint service (RMPS) and multipoint to multipoint service
  • Maintain and update of MSR
  • Develop additional Recommendations from progress on the above study items.
NOTE: An up-to-date status of work under this Question is contained in the SG15 Work Programme at:
  • G.705, G.707, G.709, G.781, G.783, G.784, G.798, G.798.1, G.806, G.872, G.874, G.7710, G.8021, G.8051,  G.8080, G.8010, G.8110, G.8021, G.8110.1, G.8121, G.993.x, Y.2601 and Y.2611
  • Q3/15, Q4/15, Q6/15, Q10/15, Q11/15, Q12/15, Q13/15 and Q14/15.
Study Groups:
  • ITU-T SG2 responsible for telecommunication management
  • ITU-T SG13 responsible for NGN aspects
  • ITU-T SG12 responsible for Ethernet and MPLS error performance
Standardization bodies, forums and consortia:
  • IETF working groups related to MPLS-TP protection
  • MEF on Ethernet Equipment Protection
  • IEEE 802.1, 802.3 on Ethernet Protection
  • Broadband Forum