W. Feng and R.T. Hurley (Canada)
Birth-Death process, server utilization, mean response
time, Poisson process, system throughput.
In this paper, we discussed three Birth-Death models
for service systems, such as telephone call centers or
Internet access points. The first model assumes that
customers have no information about the system and so
they may balk or renege upon arrival. The other two
models assume that customers receive the state
information as they arrive and thus, the balking
probability is state-dependant. Model 2 uses the
assumption that the balking probabilities depend on a
waiting time threshold while Model 3 assumes that the
balking probabilities depend directly on the number of
customers in the waiting queue.
Both analysis and simulation are used to investigate
the performance of the systems based on the three models.
We compare the server utilization and mean response
time. Our results indicate that Model 2 tends to have a
lower response time than Model 1 and the performance of
a system based on Model 3 greatly depends on the
sequence of balking probabilities. We show the results
for two such scenarios.