Introduction to queueing theory: basic characteristics of queues, performance measures, queue length process. Simple Markovian queueing systems, stationary distribution, M/M/1 queues, equilibrium distribution. Probability generators and Markovian queueing systems: M/M/k queue with heterogeneous servers, E2/E2/1/1 queue, M/Es/1 queue, Er/M/1 queue, M/E2/2/2 queue. Markovian queueing networks, Probabilistic analysis of M/M/1 queue, Jackson networks, stationary distribution of Jackson networks. Markovian service systems, systems with variable number of servers.