BlockOut: Blocking and Outage in a Single Performance Measure

Blocking probability is widely used as a performance measure for dimensioning a variety of networks, including wireless communication systems. However, the performance of the system may be affected by factors other than traffic and resources, i.e., the primary ingredients in blocking. Such factors include interference, energy consumption, service delay restriction, and others. In this case, blocking by itself does not fully convey the extent of the system quality of service (QoS). Those other phenomena may lead the system to experience an outage, in which case resources, even if available, cannot be used because of the performance degradation that this may incur. In this paper, we propose a performance measure, i.e., BlockOut probability, that combines blocking and outage in one parameter. Exact, closed-form, and recursive forms of this parameter are presented, and a simple example of application is shown. The BlockOut probability encompasses the well-known Erlang-B formula as a special case. Although the application example focuses on wireless systems, BlockOut may find use in a variety of other networks.