Modeling leader-based multicast transmission via periodic reservations in Wi-Fi networks

摘要

For a long time Wi-Fi has lacked methods for reliable multicast. A great step towards solving this problem has been made with release of the IEEE 802.11aa amendment, which introduces a number of new multicast methods. The amendment claims that reliability of the methods can be increased if transmission is performed in preliminarily reserved time intervals. If a transmitted flow imposes certain Quality of Service (QoS) requirements, parameters of such reservation-based multicast need to be appropriately adjusted to satisfy QoS at all receivers. In the paper, we consider QoS-aware multicasting of a variable bit rate (VBR) flow by means of periodic channel reservations. The core contribution of the paper is a generalized mathematical model which can be used to analyze efficiency of any of the standardized multicast methods. Particularly, the model can be used to find such transmission parameters, which guarantee that QoS requirements are satisfied at all receivers at the minimal amount of the reserved channel time.