Figure 2.3: Application scenarios 
2.5 WiMAX forum and adaptation of IEEE 802.16
The Worldwide Interoperability for Microwave Access (WiMAX) forum is an alliance of telecommunication equipments and components manufacturers and service providers, formed to promote and certify the compatibility and interoperability of BWA products employing the IEEE 802.16 and ETSI HiperMAN  wireless specifications. WiMAX Forum Certified™ equipment is proven interoperable with other vendors’equipment that is also WiMAX Forum Certified™ . So far WiMAX forum has setup certification laboratories in Spain, Korea and China. Additionally, the WiMAX forum creates what it calls system profiles, which are specific implementations, selections of options within the standard, to suit particular ensembles of service offerings and subscriber populations .
WiMAX forum has adopted two version of the IEEE 802.16 standard to provide different types of access: