Wi fi

C O N T E N T S

• INTRODUCTION• TECHNICAL ASPECTS• EQUIPMENTS• WI-FI STANDARDS• ELEMENTS OF WI-FI NETWORKS• NETWORK TOPOLOGIES• SECURITY• AUTHENTICATION• APPLICATION• ADVANTAGES• LIMITATION

What is Wi-Fi ??

Connecting to WiFi

Technical Aspects Overview

Equipment For Wi-Fi

Typically Wi-Fi requires 3 main pieces to

be in place:

Wi-Fi Standards

802.11a 5 GHz band

802.11b 2.40 GHz band

802.11g 2.40 GHz band

802.11n 2.4

or 5GHz band

Wi-Fi Standards Cont.

802.11a :

Wi-Fi Standards Cont.

802.11 b:

Wi-Fi Standards Cont.

802.11 g:

Wi-Fi Standards Cont.

802.11 n:

Elements of a WI-FI Network

How a Wi-Fi Network Works

Wi-Fi Network Topologies

1

2

3

AP-based topology

.

Peer-to-peer topology

Point-to-multipoint bridge topology

Wi-Fi Security

The requirements for Wi-Fi network securitycan be broken down into two primarycomponents:

Authentication

User Authentication

Server Authentication

Privacy

Authentication

Keeping unauthorized users off the network

User Authentication

Authentication Server is used

Username and password

Risk:

Data (username & password) send before secure channel established

Prone to passive eavesdropping by attacker

Solution

Establishing a encrypted channel before sending username and password

Wi-Fi Applications

Advantages

Mobility

Ease of Installation

Flexibility

Cost

Reliability

Security

Use unlicensed part of the radio spectrum

Roaming

Speed

Interference

Degradation in performance

High power consumption

Limited range