A Multicast Mechanism in WiMax Mesh Network

The IEEE standard 802.16x based broadband wireless access is a promising technology to provide wireless broadband connectivity. Besides point to multi-point mode, a mechanism to create multi-hop network through mesh mode is defined for the frequency spectrum band 2-11 GHz. The standard only defines unicast transmission under mesh mode, but does not specify multicast transmission scheme. This paper proposes a novel multicast mechanism in WiMax mesh network by building a high efficient multicast tree with utilization of scheduling messages defined in the standard. An easy-to-implement tree construction algorithm is presented based on the adjustment of the centralized routing tree. Simulation results show the proposed multicast mechanism improves transmission efficiency and reduces group latency over the traditional way to fulfil multicast by multiple unicast transmissions