Performance analysis of multicast transmission in WLAN

In this paper point-to-multipoint (PMP) transmission on the link layer in ad hoc networks based on the WLAN standard IEEE 802.11 is investigated. Besides the basic access scheme for multicast/broadcast, which is defined in the standard, two alternative schemes are introduced, which make use of the request-to-send (RTS) and clear-to-send (CTS) handshaking. This two-way handshaking is specified in the standards documents only for unicast connections and should be applied for large packets and to combat hidden stations. However, with slight modifications of the respective control packets it can be applied also for PMP transmission and performance evaluations of the different approaches indicate considerable enhancements in reliability for the proposed schemes compared to the one specified in the standard.