Fault Tolerance and Load Balancing in QoS Provisioning with Multiple MPLS Paths
The paper presents approaches for fault tolerance and load balancing in QoS provisioning using multiple alternate paths. The proposed multiple QoS path computation algorithm searches for maximally disjoint (i.e., minimally overlapped) multiple paths such that the impact of link/node failures becomes significantly reduced, and the use of multiple paths renders QoS services more robust in unreliable network conditions. The algorithm is not limited to finding fully disjoint paths. It also exploits partially disjoint paths by carefully selecting and retaining common links in order to produce more options. Moreover, it offers the benefits of load balancing in normal operating conditions by deploying appropriate call allocation methods according to traffic characteristics. In all cases, all the computed paths must satisfy given multiple QoS constraints. Simulation experiments with IP Telephony service illustrate the fault tolerance and load balancing features of the proposed scheme.
KeywordsLoad Balance Fault Tolerance Link Failure Multiple Path Disjoint Path
Unable to display preview. Download preview PDF.
- 1.D. Cavendish and M. Gerla, Internet QoS Routing using the Bellman-Ford Algorithm, Proceedings of IFIP Conference on High Performance Networking, Austria,1998.Google Scholar
- 2.R. Guerin, A. Orda, and D. Williams, QoS Routing Mechanisms and OSPF Extensions, In Proceedings of GLOBECOM’97, Vol. 3, pp. 1903–1908, Phoenix, Arizona.Google Scholar
- 3.J. Moy, OSPF Version 2, RFC 2328, April 1998.Google Scholar
- 4.E. Rosen, A. Viswanathan, and R. Callon, Multiprotocol Label Switching Architecture, RFC 3031, January 2001.Google Scholar
- 5.A. Dubrovsky, M. Gerla, S. S. Lee, and D. Cavendish, Internet QoS Routing with IP Telephony and TCP Traffic, In Proceedings of ICC’00, New Orleans, June 2000.Google Scholar
- 6.A. Fei and M. Gerla, Smart Forwarding Technique for Routing with Multiple QoS Constraints, In Proceedings of GLOBECOM’00.Google Scholar
- 7.A. W. Brander and M. C. Sinclair, A Comparative Study of k-Shortest Path Algorithms, In Proceedings of 11th UK Performance Engineering Workshop, Liverpool, September 1995.Google Scholar
- 8.D. Eppstein, Finding the k Shortest Paths, SIAM Journal on Computing, vol.28, (no.2), SIAM, 1998.Google Scholar
- 9.H. Schulzrinne, S. Casner, R. Frederick, and V. Jacobson, RTP: A Transport Protocol for Real-Time Applications, RFC 1889, January 1996.Google Scholar