We examine a multi-server queueing system with Poisson arrivals in which customers require simultaneous service from a random number of servers. Servers assigned to the same customer begin and end service concurrently. Service times are, in general, assumed to be exponentially distributed. A...

We examine a queueing system with multiple primary servers and a fewer number of auxiliary servers. There are two classes of customers---those who require service from a primary server working alone and those who require service from a primary server who is assisted by an auxiliary server....