A Survey on Queueing Systems with Mathematical Models and Applications

3.1. The Arrival Process of Customers

The inter-arrival times are assumed to be independent having a common distribution. In many practical situations, customers arrive according to a Poisson stream (i.e. exponential inter-arrival times). Customers may arrive one by one or in batches. An example of batch arrivals is the customs office at the border where travel documents of passengers are to be checked.