Lattice path approach for busy period density of M/G/1 queues using C3 Coxian distribution

The paper aims at busy period analysis of non-Markovian queuing system M/G/1 starting initially with i0 customers, through lattice path approach. The general distribution involved is approximated by a 3-phase Cox distribution, C3. Distributions having rational Laplace–Stieltjes transforms and square coefficient of variation lying in [1/3, ∞) form a very wide class of distributions. As any distribution of this class can be approximated by a C3, that has Markovian property, amenable to the application of lattice paths combinatorial analysis, the use of C3 therefore has led us to achieve results applicable to almost any real life queuing system M/G/1.