The IEEE802.16 standard defines five Quality of Service (QoS) classes.
Unsolicited Grant Service (UGS)
UGS was designed to accommodate services that create fixed-size data packets on a regular basis. This class offers grants on a periodic basis and removes the need for subscriber unit access requests. This QoS class works well with VoIP traffic.
Extended Real-time Polling Service (ertPS)
ertPS is a middle ground between UGS and rtPS. It is designed for real-time traffic with variable data rate such as VoIP with silence suppression enabled.
Real-time Polling Service (rtPS)
rtPS was designed with services like video streaming in mind. It allows the subscriber unit to request bandwidth based on the needs of the data stream.
Non-real-time Polling Service (nrtPS)
nrtPS provides variable size data grants for non-real-time services such as high bandwidth FTP. This service ensures that flows receive attention even during periods of network congestion.
Finally, Best Effort service is defined for data streams which have no minimum service level. HTTP is one protocol that will often be defined as Best Effort.
As of February 2009, Cisco's WiMAX product (known as Broadband Wireless) only supported UGS and Best Effort.