WiMAX connectivity uses two components, a Base Station (BS), where the WiMAX signals are broadcast and a Subscriber Station (SS) which is a device, or a group of devices that receives the signals. The SS will request bandwidth in the uplink (UL) from the BS, and the BS will allocate the bandwidth accordingly. As WiMAX can achieve a range of 30 miles with a throughput of 72 Mbps with LOS and 4 miles with NLOS, promoting mobility but maintain effective QoS is difficult. QoS is challenging to achieve due to unpredictable channel conditions such as signal fading and frequency interference. Different types of traffic will require different services from a network, including differing priority status; bandwidth levels and latency tolerances For example, electronic mail is insensitive to delay, but loss of data is its priority, compared to video, which is delay sensitive but data loss insensitive within a certain tolerance. Applications such as interactive graphics are sensitive to both delay and data loss. This paper proposes a QoS bandwidth allocation algorithm that would sample what has been transmitted so far on a periodic basis and compare to the total amount of bandwidth that SS has allocated to it. If there is a significant difference, the bandwidth allocation can be cut down allowing that bandwidth to be relocated to another SS. This would ensure that the bandwidth is directed to the transmissions that actually require it rather on the assumption of bandwidth requirement based on the classification of data being transmitted.
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