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The switch is the point where the client gains access to the network.. • In a wireless LAN, each client uses a wireless adapter to gain access to the.[r]
(1)CCNA – Semester 3
Chapter 7: Basic Wireless Concepts and Configuration
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Objectives
• Describe the components and operations of basic wireless LAN topologies
• Describe the components and operations of basic wireless LAN security
• Configure and verify basic wireless LAN access
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Why Use Wireless?
• Business networks today are evolving to support people who are on the move
• Mobility environment: where people can take their
connection to the network along with them on the road
• There are many different infrastructures (wired LAN, service provider networks) that allow mobility like this to happen, but in a business environment, the most important is the WLAN
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Comparing a WLAN to a LAN
• In an 802.3 Ethernet LAN, each client has a cable that connects the client NIC to a switch The switch is the point where the client gains access to the network
• In a wireless LAN, each client uses a wireless adapter to gain access to the
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Configurable Parameters for Wireless Endpoints
• Wireless mode
• Wireless Network Name: SSID
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Client and Access Point Association
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Client and Access Point Association
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Wireless LAN Security Threats
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Wireless LAN Security Threats
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Wireless Security Protocols
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Security Mode
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Mode Parameters
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Select the Wireless Security Protocol
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Troubleshooting
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Systematic Approach to WLAN Troubleshooting
• Step - Eliminate the client device as the source of the problem
• Step - Confirm the physical status of WLAN devices
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Solving RF Interference
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Site Survey
• Two categories: Manual and utility assisted
• Manual site surveys can include a site evaluation to be followed by a more thorough utility-assisted site survey A site evaluation involves inspecting the area with the goal of identifying potential issues that could impact the network Specifically, look for the presence of multiple WLANs,
unique building structures, such as open floors and
atriums, and high client usage variances, such as those caused by differences in day or night shift staffing levels
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Access Point Misplacement: Solution
• Ensure that access points are not mounted closer than 7.9 inches (20 cm) from the body of all persons
• Do not mount the access point within feet (91.4 cm) of metal obstructions
• Install the access point away from microwave ovens Microwave ovens operate on the same frequency as the access point and can cause
signal interference
• Always mount the access point vertically (standing up or hanging down)
• Do not mount the access point outside of buildings
• Do not mount the access point on building perimeter walls, unless outside coverage is desired
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