In this short note, we derive the large deviations estimate of the tail of the buffer occupancy distribution in a communications link with a very general integrated Poisson shot noise model for the total input. The result is obtained by a straightforward application of the results of Duffield and O'Connell. The interesting outcome of these computations is that, in the light-tail case, it is largely model independent, and this makes the statistical analysis of traffic in view of link dimensioning, with a procedure implementable by a simple network-based software.