Access networks, where a number of Subscriber Stations (SSs) are centrally controlled by a Base Station (BS). The Medium Access Control (MAC) protocol is connection-oriented and time is divided into frames of fixed duration. Moreover, MAC signaling is in-band, ie any frame carries both data and control messages. Therefore, the capacity available for data transmission is affected by the overhead due to control messages whose size, in turn, depends on several factors including the number of SSs that are scheduled in a frame. In this paper, we derive a set of formulae to compute the maximum throughput of best effort traffic in an IEEE 802.16 network. To this end, we only assume that the BS fairly shares the available resources among the connections. We validate our formulae through simulation, and, finally, we exploit the proposed formulae to investigate the throughput performance of IEEE 802.16 in a set of relevant scenarios.