WiMax Problems
Stand by for some disappointments when the initial version of WiMax metropolitan area technology is deployed. If the networks do support voice over IP or other fancy applications, they’re unlikely to be part of the specification.
Part of the promise of WiMax is that it will be more than just a fat, wireless pipe — that with WiMax, service providers could enable applications like VOIP and even wireless video services. But the code that would enable such applications is not a mandated part of the initial WiMax profile from the WiMax Forum, vendors say.
In fact, the WiMax profile only defines the transport layer to be used in base stations and customer premises equipment (CPE) and lets vendors and operators chose what they want to use to implement higher-level functions like VOIP.
The Institute of Electrical and Electronics Engineers Inc. (IEEE) 802.16d standard that WiMax is based defines both the physical (PHY) and media access control (MAC) layers used in the metro-area technology. The 802.16d MAC layer sports QOS (quality-of-service) capabilities that can enable voice services and support for authentication and link privacy security (see WiMax Guide).
So, while WiMax supports QOS and security, it does not mandate higher level application support, such as support for the session initiation protocol (SIP) for VOIP. The Forum is, though, planning an “applications plugfest” to demonstrate the kind of services that can be offered over WiMax later this year, Shakouri adds.