This document provides an overview of WiMAX technology. It describes WiMAX as a wireless technology that uses radio spectrum between 2-66 GHz to provide internet connectivity over long ranges of up to 50km at speeds of up to 70 Mbps. It discusses the key components of a WiMAX system including WiMAX towers and receivers. It also covers the technical aspects of how WiMAX works including modulation methods, transmission duplexing, and the use of OFDM. The document outlines the modes of WiMAX operation and benefits. It then discusses security threats to WiMAX like eavesdropping, masquerading, message modification and DoS attacks. Finally, it mentions authentication, key exchange and encryption as security techniques for WiMAX.
2. Introduction
WiMAX stands for Worldwide Interoperability for Microwave Access.
WiMAX is the trade name of “IEEE 802.16 standard”.
Radio spectrum from 10-66 GHz and 2-11 GHz for unlicensed and licensed bands
Range up to 31 miles (50km)
Speed up to 70 Megabits
It is going to be an emerging technology for the future
It is featured with Voice, Video, Real time video conferencing and other services
It is next generation of wifi technology which allows us to connect to the internet with
higher speed and in wider range.
3. Introduction continue…
Modulation method in the download and uplink are BPSK (Binary Phase Shift Keying), QPSK
(Quaternary Phase Shift Keying), 16-QAM, 64-QAM
Supports two types of transmission duplexing: Time Division Duplexing (TDD) and Frequency
Division Duplexing (FDD) and supports both half and full duplex method.
TDD- both the uplink and downlink share the same frequency but are separated on time
FDD- both uplink and downlink communication take place at the same time but on
different frequency
WiMAX uses OFDM (Orthogonal Frequency Division Multiplexing) technology.
4. A WIMAX system consists of
WiMAX Tower:
similar to the concept of cell-phone tower. Single tower can provide coverage up to 3,000 square
miles.
WiMAX Receiver:
it may be the small box like devices as modem and they could be build into the laptop
5. How it Works
A subscriber sends the wireless traffic at the speed 2M-155Mbps from fixed antenna
The base station receives the traffic signal from multiple sites and sends to the switching
center through wired or wireless using 802.16 protocol.
The switching center sends the traffic to the ISP or PSTN (Public Switched Telephone
Network)
Switching
Center
Base
Station
ISP
Subscriber
6. Modes of Operation
Non- Line of Sight (Data is transmitted from tower to subscriber)
Use a lower frequency range (2-11GHz)
Line of Sight (Data is transmitted from one tower to another tower)
Use a higher frequency range (66GHz)
7. Benefits of WiMAX
Speed
Faster than broadband services
Wireless
Not having to lay cable reduces cost
Easier to extend to rural and urban areas
Broad coverage
Much wider range of coverage area than wifi
8. THREAT ANALYSYS
o Critical threats are
o eavesdropping of management messages,
o BS or MS masquerading,
o management message modification and DoS attack.
9. Eavesdropping
Management messages (not encrypted) can provide valuable
information (credit card no)to an attacker.
From the user perspective, eavesdropping of management
messages may result in limited financial loss.
10. Masquerading means
IP spoofing: send packet with false source address.
Instead of sending packet to server, client send it to Hacker.
record-and-playback: take out sensitive info (e.g., password), and
use later C Hacker
takes
A hacker identity of
server.
server
B client
11. What is a DoS Attack?
o The act of denying a computer user of a particular
service.( user or client not able to connect to server or
internet.)
o It involves flooding a host until it cannot respond to
legitimate traffic
12. Other Major Threats are
Jamming
Block WiMAX by sending the radio wave of same frequency used by WiMAX which
cause enough interference
Data Traffic Modification