Dynamic Resource Reservation in IEEE 802.16 Broadband Wireless Networks

This paper presents a mechanism for dynamic resource management and discusses its relevance for traffic in IEEE 802.16 broadband wireless network. The basic goal is to minimize the amount of bandwidth being actually provisioned for committed bandwidth traffic while keeping the cost of MAC signalling to a minimum. In particular, this mechanism restricts the provisioned bandwidth to a predefined minimum when the actual offered load is significantly lower than the load that has been taken as a dimensioning objective. The proposed mechanism dynamically changes the amount of reserved resources between a small number of values (two in the base model) depending on the actual number of active connections while limiting the number of transitions by imposing a hysteresis behaviour. In particular, it is not necessary to update the resource reservation whenever a traffic flow is activated or terminated. A Markov chain model yields two performance parameters: the reserved bandwidth and the transition rate. A new parameter, noted thetas, has been introduced in addition to the performance parameters discussed to minimize the global cost of the system. A generalization of this method to more than a single threshold is also proposed and discussed