t to stream video to a handheld media player will translate into technical attributes for QoS and very high data rate. Evaluating Available Technologies Having established the technical attributes necessary to meet user requirements, the available technologies can then be directly assessed against these attributes. A simple table can be used to display the comparison, similar to the example shown in Table 11-3. Although the range of available PAN technologies is growing, the choice is still sufficiently narrow not to require sophisticated evaluation methods, such as assigning a relative weight to the various requirements. This approach will result in a transparent and objective comparison of the available solutions, but an independent reality check will always be helpful to verify the proposed solution - to ensure that no requirements have been missed and no limitations of a particular technology have been overlooked. It is also helpful to research the solutions that have been adopted by others to meet similar needs. If no examples can be found of the proposed solution being used in practice (IrDA for last mile broadband access?) then either a new technology application has been spotted or something has been missed in the evaluation. Table 11-3: PAN Technologies; Technical Attribute Comparison Requirement type Bluetooth ZigBee Effective data rate ca. 3 Mbps 480 Mbps 250 kbps ca. 2 Mbps 16 Mbps (2.0) (VFIR) Quality of service Interference and coexistence Power consumption Very low Very low Technology maturity Very mature mature Operating range < 10 m 10-30 m 70-300 m < 0.2 m Chapter Eleven Pilot Testing If the PAN implementation project is targeting a significant number of users then, as for WLAN implementation, a pilot testing phase will be beneficial. This will be the opportunity to confirm that the statement of user requirements is clear and complete, and that the users' performance expectations are also well defined and can be met by the proposed solution. The group of users chosen for the pilot test should co