Protection Switching Methods for Point-to-Multipoint Connections in Packet Transport Networks

  • Kim, Dae-Ub (Communications & Internet Research Laboratory, ETRI, Department of Information and Communications Engineering, Chungnam National University) ;
  • Ryoo, Jeong-dong (Communications & Internet Research Laboratory, ETRI, Department of Engineering, Korea University of Science and Technology) ;
  • Lee, Jong Hyun (Communications & Internet Research Laboratory, ETRI) ;
  • Kim, Byung Chul (Department of Information and Communications Engineering, Chungnam National University) ;
  • Lee, Jae Yong (Department of Information and Communications Engineering, Chungnam National University)
  • Received : 2015.02.06
  • Accepted : 2015.10.21
  • Published : 2016.02.01


In this paper, we discuss the issues of providing protection for point-to-multipoint connections in both Ethernet and MPLS-TP-based packet transport networks. We introduce two types of per-leaf protection-linear and ring. Neither of the two types requires that modifications to existing standards be made. Their performances can be improved by a collective signal fail mechanism proposed in this paper. In addition, two schemes - tree protection and hybrid protection - are newly proposed to reduce the service recovery time when a single failure leads to multiple signal fail events, which in turn places a significant amount of processing burden upon a root node. The behavior of the tree protection protocol is designed with minimal modifications to existing standards. The hybrid protection scheme is devised to maximize the benefits of per-leaf protection and tree protection. To observe how well each scheme achieves an efficient traffic recovery, we evaluate their performances using a test bed as well as computer simulation based on the formulae found in this paper.


Grant : Terabit optical-circuit-packet converged switching system technology development for the next-generation optical transport network

Supported by : IITP


  1. ITU-T Rec. G.8031/Y.1342, Ethernet Linear Protection Switching, June 2011.
  2. IETF RFC 7271, MPLS Transport Profile (MPLS-TP) Linear Protection to Match the Operational Expectations of Synchronous Digital Hierarchy, Opt. Transport Network, and Ethernet Transport Network Operators, June 2014.
  3. ITU-T Rec. G.8131/Y.1382, Linear Protection Switching for MPLS Transport Profile (MPLS-TP), July 2014.
  4. IETF RFC 6378, MPLS Transport Profile (MPLS-TP) Linear Protection, Oct. 2011.
  5. J.-D. Ryoo et al., "MPLS-TP Linear Protection for ITU-T and IETF," IEEE Commun. Mag., vol. 52, no. 12, 2014, pp. 16-21.
  6. ITU-T Rec. G.8032/Y.1343, Ethernet Ring Protection Switching, Feb. 2012.
  7. J.-D. Ryoo et al., "Ethernet Ring Protection for Carrier Ethernet Networks," IEEE Commun. Mag., vol. 46, no. 9, Sept. 2008, pp. 136-143.
  8. J.K. Rhee, J. Im, and J.-D. Ryoo, "Ethernet Ring Protection Using Filtering Database Flip Scheme for Minimum Capacity Requirement," ETRI J., vol. 30, no. 6, Dec. 2008, pp. 874-876.
  9. K.-K. Lee, J.-D. Ryoo, and S. Min, "An Ethernet Ring Protection Method to Minimize Transient Traffic by Selective FDB Advertisement," ETRI J., vol. 31, no. 5, Oct. 2009, pp. 631-633.
  10. K.-K. Lee, J.-D. Ryoo, and Y. Kim, "Impacts of Hierarchy in Ethernet Ring Networks on Service Resiliency," ETRI J., vol. 34, no. 2, Apr. 2012, pp. 199-209.
  11. K.-K. Lee and J.-D. Ryoo, "Flush Optimization to Guarantee Less Transient Traffic in Ethernet Ring Protection," ETRI J., vol. 32, no. 2, Apr. 2010, pp. 184-194.
  12. K.-K. Lee, C.-K. Lee, and J.-D. Ryoo, "Enhanced Protection Schemes to Guarantee Consistent Filtering Database in Ethernet Rings," IEEE Global Commun. Conf., Miami, FL, USA, Dec. 6-10, 2010, pp. 1-6.
  13. The Metro Ethernet Forum MEF 10.2, Ethernet Services Attributes Phase 2, Oct. 2009.
  14. J.-D. Ryoo et al., "OAM and its Performance Monitoring Mechanisms for Carrier Ethernet Transport Networks," IEEE Commun. Mag., vol. 46, no. 3, Mar. 2008, pp. 97-103.
  15. OPNET Technologies Inc. Accessed Oct. 2012.
  16. M. Huynh, S. Goose, and P. Mohapatra, "Resilience Technologies in Ethernet," Comput. Netw., vol. 54, no. 1, Jan. 2010, pp. 57-78.
  17. ITU-T Rec. G.808.1, Generic Protection Switching - Linear Trail and Subnetwork Protection, May 2014.