Restoration strategies and spare capacity requirements in self-healing ATM networks

This paper studies the capacity and flow assignment problem arising in the design of self-healing ATM networks using the virtual path (VP) concept. The problem is formulated as a linear programming problem which is solved using standard methods. The objective is to minimize the spare capacity cost for the given restoration requirement. The spare cost depends on the restoration strategies used in the network. We compare several restoration strategies, notably, global versus failure-oriented reconfiguration, path versus link based restoration and state-dependent versus state-independent restoration, quantitatively in terms of spare cost. The advantages and disadvanages of various restoration strategies are also highlighted. Such comparisons provide useful guidance for real network design. Further, a new heuristic algorithm is developed for the design of large self-healing ATM networks using path based restoration. Numerical results illustrate that the heuristic algorithm is efficient and can give near-optimal solutions for spare capacity allocation and flow assignment