ion and signal strength in the operating area, a provisional physical layout of the WLAN can be created. The objective of this stage is to establish a layout of hardware that will ensure complete RF coverage and deliver the required bandwidth to wireless client stations. Chapter Seven R Live File Edit View Actions Help Map Type AP-Coverage Caverage Rate : Layered SNR Channel All Merged Alpha Alpha HQ Floor1 AP Count 18 AM Count :6 Grid HQ Floors Floori Main Campus 1.127457 4991573 1161.a 11/1/157x 11.1.15/M63.a. 1.1.43/161.a 1.1.44/163a 21/157a 1:16:15 1-4 247 Areas Suggested APs/AMs Deployed APs Bottom Right Details 133,44 Figure 7-1: Display of Propagation and Signal Strength Survey Results (Courtesy of Aruba Wireless Networks Inc.) Network Physical Layout Design Planning the physical architecture starts with the floor plans of the operating area and the results of the propagation and signal strength survey, and results in a layout plan detailing; the required number of access points an optimal antenna type and location non-conflicting operating channel proper power setting for each access point. Factors influencing physical layout are described in Table 7-9. The channel allocation patterns shown in Figure 7-2 are based on the three non-overlapping channels 1, 6 and 11 in the 2.4 GHz band. However, in those regulatory domains that permit 13 channels in this band (Europe, Japan, etc., as discussed in the Section "802.11b PHY Layer, Implementing Wireless LANs Table 7-9: Factors Influencing WLAN Physical Architecture Parameter Factors influencing the physical architecture Number A preliminary count can be established by dividing the overall operating area per access point by the coverage area determined from the propagation and signal strength survey. The area should be taken out to the contour at which the required data rate could be maintained. The effective coverage area of an access point will be reduced if the propagation pattern is far from omnidirectional as a result of nearby obstacles. Optimal antenna The