ABSTRACT
The following standard notation is used to characterize systems with a single queue in equilibrium, identical parallel servers, unlimited waiting room, and first-come, first-served queueing discipline. Each system is defined by
A/B/m
where
A
denotes the distribution of interarrival times
B
denotes the distribution of service times
m
denotes the number of servers in parallel
Commonly used symbols for both the
A
and
B
positions in this notation are
M
and
G
. The symbol
M
is used for the exponential distribution to denote its Markovian (“memoryless”) property. The symbol
G
is used for a general distribution of independent and identically distributed random variables. For example, an
M
/
G
/1 queue has exponentially distributed interarrival times, a general distribution for service times, and one server. A
G
/
G
/
m
queue has general distributions for interarrival times and service times, and
m
servers in parallel. (Gross and Harris, 1985; Kendall, 1953; Wolff, 1989).
