Combined fast-routing and bandwidth-reservation algorithm for ATM networks

Traditionally, the task of establishing a connection in connection-oriented networks is divided into two subtasks. First, a route is selected based on a topology database that is maintained in every node according to some optimization rule, such as, shortest path, minimal delay, etc. After the route is selected, the source tries to allocate resources (such as bandwidth, buffers, etc.) along the selected route. A failure to reserve resources along the selected route causes the source to give-up on the connection or to retry, i.e., look for another route and then try to reserve resources along it. The delay imposed by such a failure, especially for long haul ATM networks, might be too long for many bursty applications, e.g., queries to distributed databases. In this work we suggest a more efficient scheme where the search for the optimal route and the resource allocation along it are combined. We present (few members of) a family of algorithms that enables the application planner to select the suitable trade-off between optimal route selection and the speed of establishing the route. Asymptotic complexity analysis is given for the presented algorithms.