IEEE 802.16 Qos Classes (or Service Classes)

BE		Best Effort. Used for lowest priority time-constraint services such as email
ertPS		Extended real-time Polling Service. New QoS class defined in the 802.16e amendment. Intermediary between rtPS and UGS
nrtPS		Non-real-time Polling Services. Used for non-real-time services having some time constraints
rtPS		Real-time Polling Services. Used for variable data rate real-time services. Example is the MPEG video
UGS		Unsolicited Grant Services. Dedicated to Constant Bit Rate (CBR) services, UGS guarantees fixed-size data packets issued at periodic inervals. Example of use is T1/E1 transmissions