CWNA Guide to Wireless LANs, Second Edition 1 Planning for a Wireless Network “If you fail to plan, then you plan to fail” Some steps involved in planning wireless networks similar to planning wired network – Many steps significantly different Basic planning steps: – Assessing needs – Weighing benefits – Calculating costs

CWNA Guide to Wireless LANs, Second Edition 2 Assessing Needs: Reviewing the Current Network (continued) Table 6-1: Current network table

CWNA Guide to Wireless LANs, Second Edition 3 Assessing Needs: Reviewing the Current Network (continued) Figure 6-1: Network diagram

CWNA Guide to Wireless LANs, Second Edition 4 Determining Benefits Hard Benefits Soft Benefits

CWNA Guide to Wireless LANs, Second Edition5 Calculating Return on Investment Intel Corporation’s wireless LAN model: – Implement a pilot – Develop a report – Assemble data – Calculate ROI Table 6-2: Three-year WLAN costs and benefits

CWNA Guide to Wireless LANs, Second Edition 6 Designing the Wireless LAN Involves determining: – Which deployment scenario is best – Which IEEE wireless network standard should be used – Type of AP management to implemented – Where wireless devices should be located

CWNA Guide to Wireless LANs, Second Edition 7 Determining the Location of the Wireless Devices Table 6-3: Interference by objects

CWNA Guide to Wireless LANs, Second Edition 8 Ad Hoc Mode Figure 6-3: Ad hoc hidden node problem

CWNA Guide to Wireless LANs, Second Edition 9 Infrastructure Mode Figure 6-4: Interference from using same channel

CWNA Guide to Wireless LANs, Second Edition 10 Infrastructure Mode (continued) Figure 6-5: Channel reuse

CWNA Guide to Wireless LANs, Second Edition 11 Infrastructure Mode (continued) Figure 6-6: Flip flop between access points

CWNA Guide to Wireless LANs, Second Edition 12 Deploying a Wireless Network If planning/designing done correctly, deploying can be easiest step Must consider actual placement of APs – Place APs exactly where they were designed to go – To avoid interference, better to place APs higher Be careful if placing APs in plenums If needed, can use PoE Good idea to configure WLAN on own network segment

CWNA Guide to Wireless LANs, Second Edition 13 Providing User Support Training Support

CWNA Guide to Wireless LANs, Second Edition 14 What is a Site Survey? Design goals for a site survey: – Achieve best possible performance from WLAN – Certify that installation will operate as promised – Determine best location for APs – Develop networks optimized for variety of applications – Ensure coverage will fulfill organization’s requirements – Locate unauthorized APs

CWNA Guide to Wireless LANs, Second Edition 15 What is a Site Survey? (continued) When to perform a site survey: – Before installing a new wireless network – Before changing an existing wireless network – When there are significant changes in personnel – When there are changes in network needs – After making physical changes to a building

CWNA Guide to Wireless LANs, Second Edition 16 Site Survey Tools: Wireless Tools Figure 7-1: Adjusting AP power levels

CWNA Guide to Wireless LANs, Second Edition 17 Site Survey Tools: Wireless Tools (continued) Figure 7-2: External antenna connectors

CWNA Guide to Wireless LANs, Second Edition 18 Site Survey Tools: Measurement Tools Figure 7-3: Full-featured site survey analyzer software setup

CWNA Guide to Wireless LANs, Second Edition 19 Site Survey Tools: Measurement Tools (continued) Figure 7-4: Full-featured site survey analyzer software results

CWNA Guide to Wireless LANs, Second Edition 20 Site Survey Tools: Measurement Tools (continued) Figure 7-6: Basic site survey analyzer software results

CWNA Guide to Wireless LANs, Second Edition 21 Site Survey Tools: Measurement Tools (continued) Figure 7-8: Spectrum analyzer

CWNA Guide to Wireless LANs, Second Edition 22 Site Survey Tools: Documentation Tools Figure 7-9: Sample site survey form

CWNA Guide to Wireless LANs, Second Edition 23 Performing a Site Survey: Gathering Data Obtaining Business Requirements Defining Security Requirements Gathering Site-Specific Documentation Documenting Existing Network Characteristics

CWNA Guide to Wireless LANs, Second Edition 24 Performing a Site Survey: Performing the Survey Figure 7-10: Position of APs

CWNA Guide to Wireless LANs, Second Edition 25 Performing a Site Survey: Performing the Survey (continued) Figure 7-11: Coverage pattern

CWNA Guide to Wireless LANs, Second Edition 26 Performing a Site Survey: Performing the Survey (continued) Figure 7-12: Data rate boundaries

CWNA Guide to Wireless LANs, Second Edition 27 Performing a Site Survey: Creating the Site Survey Report Figure 7-13: Table of measurements

CWNA Guide to Wireless LANs, Second Edition 28 Performing a Site Survey: Creating the Site Survey Report (continued) Figure 7-14: Data rate coverage map

CWNA Guide to Wireless LANs, Second Edition 29 Performing a Site Survey: Creating the Site Survey Report (continued) Figure 7-15: 3-D signal-to-noise ratio plot