Dynamic Constrained Traffic Engineering for Multicast Routing

This paper presents a new traÆc engineering technique for dynamic constrained multicast routing, where routing request of traÆc arrives one-by-one. The objective we adopted in this paper is to minimize the maximum of link utilization. Although this traÆc engineering is useful to relax the most heavily congested link in Internet backbone, the total network resources, i.e. sum of link bandwidth consumed, could be used when the acquired path is larger(in terms of number of hops) than the conventional shortest path. Accordingly we nd a multicast tree for routing request that satis es the hop-count constraint. We formulate this problem as mixed-integer programming problem and propose a new heuristic algorithm to nd a multicast tree for multicast routing request. The presented heuristic algorithm uses link-state information, i.e. link utilization, for multicast tree selection and is amenable to distributed implementation. The extensive simulation results show that the proposed traÆc engineering technique and heurisitc algorithm eÆciently minimize the maximum of link utilization better than the shortest path.