Design of survivable VPN based VoIP networks

This paper addresses the issue of survivable voice over IP (VoIP) network design. In the applied model the whole VoIP network is divided into two logical components: the access network and the transport network. The access network consists of VoIP end-points, which connect to the transport network through edge routers serving as gateways. Thus, one task of the design process is to assign gateways to the VoIP end-points. To assure security and availability for the VoIP traffic, a virtual private network (VPN) is assumed as transport network in this paper; therefore, the other task is to specify the transport VPN in the most economical way, while also taking the possible failures of transport network elements into consideration. Assuming a single failure at a time, the survivability of the VoIP network can be assured by assigning two gateways, namely a primary and a backup one, to each VoIP end-point, and calculating two disjoint paths between each pair of gateways. The two tasks of survivable VoIP network design can be solved separately; however, in this paper, a novel solution is proposed in which the edge router assignment process takes both the objective function of VPN specification and the issues of survivability into consideration. Multiple methods realizing the novel approach are presented, which are based on the paradigms of evolutionary algorithms and simulated annealing. The performance of the presented methods is evaluated with the help of simulations, using a well-known greedy algorithm as reference. It is shown that the proposed methods outperform the reference algorithm significantly in the simulation scenarios investigated.

[1]  Robert E. Tarjan,et al.  A quick method for finding shortest pairs of disjoint paths , 1984, Networks.

[2]  Albert-László Barabási,et al.  Statistical mechanics of complex networks , 2001, ArXiv.

[3]  W. D. Grover,et al.  VP-BASED ATM NETWORK DESIGN WITH CONTROLLED OVER-SUBSCRIPTION OF RESTORATION CAPACITY , 1998 .

[4]  J. Beasley,et al.  A genetic algorithm for the set covering problem , 1996 .

[5]  Wayne D. Grover,et al.  New options and insights for survivable transport networks , 2002, IEEE Commun. Mag..

[6]  Tibor Cinkler,et al.  Stochastic Algorithms for Design of Thrifty Single-Failure-Protected Networks , 2000 .

[7]  Zbigniew Michalewicz,et al.  Handbook of Evolutionary Computation , 1997 .

[8]  Albert,et al.  Emergence of scaling in random networks , 1999, Science.

[9]  Donald F. Towsley,et al.  On distinguishing between Internet power law topology generators , 2002, Proceedings.Twenty-First Annual Joint Conference of the IEEE Computer and Communications Societies.

[10]  Rajeev Rastogi,et al.  Algorithms for provisioning virtual private networks in the hose model , 2001, SIGCOMM 2001.

[11]  C. D. Gelatt,et al.  Optimization by Simulated Annealing , 1983, Science.

[12]  Matteo Fischetti,et al.  Algorithms for the Set Covering Problem , 2000, Ann. Oper. Res..

[13]  Mark S. Daskin,et al.  Network and Discrete Location , 1995 .

[14]  Steven Chamberland,et al.  Overall design of reliable IP networks with performance guarantees , 2000, 2000 IEEE International Conference on Communications. ICC 2000. Global Convergence Through Communications. Conference Record.

[15]  David S. Johnson,et al.  Computers and Intractability: A Guide to the Theory of NP-Completeness , 1978 .

[16]  Balx00E1zs Gx00E1bor Jx00F3zsa,et al.  An Efficient Algorithm for Global Path Optimization in MPLS Networks , 2001 .

[17]  Michalis Faloutsos,et al.  On power-law relationships of the Internet topology , 1999, SIGCOMM '99.

[18]  Eric C. Rosen,et al.  Framework for Layer 2 Virtual Private Networks (L2VPNs) , 2006, RFC.