The Wireless LAN

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]

CCNA – Semester 3

Chapter 7: Basic Wireless

Concepts and Configuration

CCNA Exploration 4.0

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

• Configure and troubleshoot wireless client access

The Wireless LAN

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

• People now expect to be connected at any time and place

Wireless Technologies

Wireless LAN

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

network through a wireless device such as

a wireless router or access point

Wireless standards

Wireless Infrastructure Components

802.11 Topologies: Ad hoc Network

802.11 Topologies: Basic Service Sets

802.11 Topologies: Extended Service

Sets

Client and Access Point Association

• Beacon

Client and Access Point Association

Client and Access Point Association

Step 3 - 802.11 Association

Planning the Wireless LAN

Planning the Wireless LAN

Planning the Wireless LAN

Planning the Wireless LAN

Wireless LAN Security

Wireless LAN Security Threats

Unauthorized Access

Wireless LAN Security Threats

Wireless LAN Security Threats

 Denial of Service

Wireless Security Protocols

Wireless Security Protocols

Wireless Security Protocols

Wireless Security Protocols

• Encryption

Securing a Wireless LAN

Configure Wireless LAN Access

Configuring the Wireless Access Point

Setup: Basic Setup

Administration: Management

Configuring Basic Wireless Settings

Security Mode

• Select the mode you want to use: PSK-Personal,

PSK2-Personal, PSK-Enterprise, PSK2-Enterprise, RADIUS, or

WEP

Mode Parameters

• Enterprise modes are not configured in this chapter

Configure Encryption and Key

Configure a wireless NIC: Scan SSID

Configure a wireless NIC: Scan SSID

Select the Wireless Security Protocol

• Practice: 7.3.2.4

Troubleshooting

Simple WLAN Problems

• Step 2 - Confirm the physical status of WLAN devices.

• Step 3 - Inspect wired links

Updating the Access Point Firmware

Incorrect Channel Settings

Incorrect Channel Settings: Solution

Solving RF Interference

Solving RF Interference

• Site Surveys

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

• Note: you do not conduct site surveys as part of this course

Access Point Misplacement

Access Point Misplacement: Solution

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 3 feet (91.4 cm) of metal

• Do not mount the access point outside of buildings.

• Do not mount the access point on building perimeter walls, unless

outside coverage is desired.

• When mounting an access point in the corner of a right-angle hallway intersection, mount it at a 45-degree angle to the two hallways The

access point internal antennas are not omnidirectional and cover a

larger area when mounted this way.

Problems with Authentication and Encrytion

Problems with Authentication and Encrytion

Problems with Authentication and Encrytion

Summary

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