Queueing theory provides a mathematical basis for understanding and predicting the behavior of communication networks.

Basic Model:

We can understand above model with below mentioned parameters:

• Inter-arrival time distribution
• Service time distribution
• Number of servers
• Queueing disciplines
• Number of buffers

Common Notion:

A/B/m

Where: ‘m’ is the number of servers
A and B can be from
M: Markov (exponential distribution / Poisson)
D: deterministic
G: General (arbitrary distribution)

M/M/1 stands for:

• Inter-arrival times are Poisson distributed (exponentially)
• Service times are exponentially distributed
• There is only one server
• The buffer is assumed to be infinite
• Queueing discipline is FCFS