The IEEE 802.15.4 protocol that provides two basic networking topologies: Star and Peer-to-Peer topologies, but fails to address mesh networks. The aim of this research is to study the about a new IEEE standard, IEEE802.15.5, which provides mesh capability for wireless personal area network (WPAN) devices. IEEE 802.15.5 consists of two parts: lowrate WPAN mesh and high-rate WPAN mesh. In this report, we present only low-rate WPAN mesh because it is designed to support wireless sensor networks. IEEE802.15.5 low-rate part is a light-weight scalable mesh routing protocol that caters well to the requirements of resource-constrained wireless sensor networks. The standard provides enhanced functions such as multicast, reliable broadcast, power saving, time synchronization, route tracing and portability. This report compares the join procedure and the rejoin procedure of IEEE802.15.5 with that offered by C skip algorithm used in protocols like zigBee and ZigBee pro. The report further discusses the multicast protocol provided by the standard and its shortcomings in terms of the end to end delay and energy consumption and suggests few modifications to the multicast protocol in order to make it more efficient in terms of energy consumption.