Protocol design of a slot allocation scheme for persistence-reservation-based IEEE 802.16d mesh networks

This paper proposes a MAC-layer timeslot allocation signaling protocol for IEEE 802.16d mesh networks. The proposed mechanism complements the three-way-handshake signaling described in the specification to achieve fair sharing of timeslots among nodes and flows. In this paper we study the case where timeslots are reserved until cancelled explicitly. This form of reservation is efficient for long sessions of data transmissions such as video streaming or interactive media applications. Since timeslots are exclusively reserved for individual flows, bandwidth starvation can occur if remaining timeslots in the wireless medium around a node are not enough to fulfill new bandwidth requests. It is thus important to design a set of mechanisms to enable sharing of network capacity across all flows fairly. A set of intra- and inter-flow fairness mechanisms is designed to work with an adaptive timeslot allocation scheme. The mechanisms and signaling are designed to efficiently integrate with the three-way-handshake signaling of the IEEE 802.16d mesh specification. Simulation results showed that the proposed schemes can prevent starvation of slot allocation and are able to maintain fairness across flows in the persistence-reservation-based IEEE 802.16d mesh network.