Optimal trajectory to overflow in a queue fed by a large number of sources

We analyse the deviant behaviour of a queue fed by a large number of traffic streams. In particular, we explicitly give the most likely trajectory (or ‘optimal path’) to buffer overflow, by applying large deviations techniques. This is done for a broad class of sources, consisting of Markov fluid sources and periodic sources. Apart from a number of ramifications of this result, we present guidelines for the numerical evaluation of the optimal path.