Decreasing call blocking probability of broadband TV services in networks with tree topology

In the provisioning of Broadband Television (BTV) services, user call blocking probability (CBP) denotes the ratio of failed user requests, which is one of the most important metrics on BTV quality of experience (QoE). This paper aims to evaluate and further to decrease the CBP of BTV services in networks with tree topology. At first, we analyze a currently typical BTV delivery network architecture, and find that an entire network can be simplified and divided into a certain number of basic 2-level tree units (B2TUs). Next, a state-vector-based simulation model is proposed to evaluate the end-to-end (E2E) CBP in a B2TU, as well as the E2E CBP in an entire BTV delivery network. After that, we elaborate an extended TV channel admission control (TCAC) scheme which can be applied in a B2TU, and further in an entire BTV delivery network. Then, a case study is carried out which illustrates the potential of our extended TCAC scheme to enhance the BTV QoE by relatively decreasing the E2E CBP up to 25%, in an entire BTV delivery network with tree topology. Finally, the robustness of our extended TCAC scheme in an even more realistic scenario is investigated by another case study.