Abstract
The WiMax standard has been developed with many objectives in mind. These are summarized below:
Objectives of WiMax
· Flexible Architecture: WiMax supports several system architectures, including Point-to-Point, Point-to-Multipoint, and ubiquitous coverage. The WiMax MAC (Media Access Control) supports Point-to-Multipoint and ubiquitous service by scheduling a time slot for each Subscriber Station (SS). If there is only one SS in the network, the WiMax Base Station (BS) will communicate with the SS on a Point-to-Point basis. A BS in a Point-to-Point configuration may use a narrower beam antenna to cover longer distances.
Description of Fixed And Mobile Wimax
High Security: WiMax supports AES (Advanced Encryption Standard) and 3DES (Triple DES, where DES is the Data Encryption Standard). By encrypting the links between the BS and the SS, WiMax provides subscribers with privacy (against eavesdropping) and security across the broadband wireless interface. Security also provides operators with strong protection against theft of service. WiMax also has built-in VLAN support, which provides protection for data that is being transmitted by different users on the same BS.
Quick Deployment: Compared with the deployment of wired solutions, WiMax requires little or no external plant construction. For example, excavation to support the trenching of cables is not required. Operators that have obtained licenses to use 5 one of the licensed bands, or that plan to use one of the unlicensed bands, do not need to submit further applications to the Government. Once the antenna and equipment are installed and powered, WiMax is ready for service. In most cases, deployment of WiMax can be completed in a matter of hours, compared with months for other solutions.
Multi-Level Service: The manner in which QoS is delivered is generally based on the Service Level Agreement (SLA) between the service provider and the end-user. Furthr, one service provider can offer different SLA s to different subscribers, or even to different users on the same SS.
Interoperability: WiMax is based on international, vendor-neutral standards, which make it easier for end-users to transport and use their SS at different locations, or with different service providers. Interoperability protects the early investment of an operator since it can select equipment from different equipment vendors, and it will continue to drive the costs of equipment down as a result of mass adoption.
Portability: As with current cellular systems, once the WiMax SS is powered up, it identifies itself, determines the characteristics of the link with the BS, as long as the SS is registered in the system database, and then negotiates its transmission characteristics accordingly.
