In this paper, we first consider single server retrial queues with two way communication. Ingoing calls arrive at the server according to a Poisson process. Service times of these calls follow an exponential distribution. If the server is idle, it starts making an outgoing call in an exponentially distributed time. The duration of outgoing calls follows another exponential distribution. An ingo...

Well-known results on the ergodicity of queues with preemptive priority were obtained under assumption that jobs arrive according to Poisson process. This assumption, however, does not always hold true in practice. In our work we find sufficient conditions for two classes a single server, where interarrival times high-priority have either Erlang or hyperexponential distribution and low-priority...

We consider systems of tandem blocking queues having a common retrial queue. The model represents dynamics of short TCP transfers in the Internet. Analytical results are available only for a specific example with two queues in tandem. We propose approximation procedures involving simple analytic expressions, based on mean value analysis (MVA) and on fixed point approach (FPA). The mean sojourn ...

Queueing models are widely used to establish stochastic models for QoS analysis of different communication environments. In [1] the authors created a queueing model to evaluate a sensor network environment with two quality classes of sources. The “Emergency” class represents the sources of very important communication (e.g. fire alarm), and the “Normal” class represents the standard communicati...

In this paper, we consider a retrial queue with state-dependent service rate as mathematical model of node FANET communications. We suppose that the arrival process is Poisson, delay duration exponentially distributed, orbit unlimited, and there multiple random access from orbit. There one server, time every call distributed variable parameter depending on number calls in The has an infinite va...

In this paper we are reviewing the retrial queue with two-way communication and Poisson arrival process. If the server free, incoming call occupies it. The call that finds the server being busy joins an orbit and retries to enter the server after some exponentially distributed time. If the server is idle, it causes the outgoing call from the outside. The outgoing call can find server free, then...