OptiFlow - A Capacity Management Tool

Intra-domain traffic engineering for routing protocols such as OSPF (open shortest path first) or intermediate system-intermediate system (IS-IS) can be performed by finding a judicious set of weights to allocate to the links of the network. Unfortunately, methods proposed in the literature for finding those weights may require a significant computational effort. By way of contrast, weight setting approaches based on linear programming can be shown in this paper to find suitable weights in the order of seconds. Prior to this time, it was necessary to determine appropriate weight settings in an off-line mode. From the results presented in this paper it can be demonstrated that solutions can be located for this problem in a matter of seconds. This makes it possible to perform traffic engineering for short term link overloads in real-time mode. The performance of this methodology has been verified by using simulation based on the well-known performance tool, ns-2. The technique described in this paper is being integrated into an optimisation module of a network capacity management tool called OptiFlow.