Performance Evaluation of Piggyback Requests in IEEE 802.16

WiMAX (Worldwide Interoperability for Microwave Access) is a wireless access technology that aims to provide last mile wireless broadband access for fixed and mobile users as an alternative to the wired DSL and cable access. It is specified in the IEEE 802.16 standard. The standard defines several possible bandwidth request methods that can be implemented in an actual deployment of a WiMAX network. In this paper, we will study the performance of two different bandwidth request mechanisms, namely piggyback and broadcast requests and will show in which situations piggybacking performs better than the contention based broadcast bandwidth requests.