WIMAX ANALYSIS

WIMAX ANALYSIS

Contents Introduction Working of WIMAX IEEE 802.16 standard 802.16 Architecture Defects of WIMAX Security Conclusion

What is WIMAX?

WIMAX stands for Worldwide Interoperability for Microwave Access

WiMAX refers to broadband wireless networks that are based on the IEEE 802.16 standard.

WiMAX, which will have a range of up to 31 miles(50 km), to make broadband network access widely available without using of stringing wires (as in cable-access broadband) or the distance limitations of Digital Subscriber Line.

Wimax and Wifi

THINK OF INTERNET There are three possible ways to

access internet. Broadband access Uses DSL or cable modem at home and

T1 or T3 line at office WIFI

Uses WIFI routers at home and hotspots on the road

Dial Up Connection

1) A WiMAX tower, similar in concept to a cell-phone tower - A single WiMAX tower can provide coverage to a very large area

as big as 3,000 square miles (~8,000 square km). 2) A WiMAX receiver - The receiver and antenna could be a

small box or Personal Computer Memory card, or they could be built into a laptop the way WiFi access is today

A WIMAX system consists of

WIMAX TOWER WIMAX RECEIVER

WIMAX CHIPS

WiMAX Mini-PCI Reference Design Intel’s first WIMAX chip

HOW WIMAX works?

MODES OF OPERATION Non-Line of sight (data is transferred from

tower to subscribers)Uses a lower frequency range.

(2-11 GHZ)

Line of sight (data is transferred from one tower to another tower)

Uses a higher frequency range. (66 GHZ)

IEEE 802.16

Range- 30 miles from base station

Speed- 70 Megabits per second

Frequency bands- 2 to 11 and 10 to 66(licensed and unlicensed bands respectively)

802.16 Architecture

P2MP ArchitectureBS connected to Public Networks

BS serves Subscriber Stations (SS)Provides SS with first mile access to Public

Networks

Mesh ArchitectureOptional architecture for WiMAX

P2MP Architecture

Mesh Architecture

BENEFITS OF WIMAX

Speed Faster than broadband service

Wireless Not having to lay cables reduces cost Easier to extend to suburban and rural areas

Broad Coverage Much wider coverage than WiFi hotspots

More ……

THREAT ANALYSYS

Critical threats are eavesdropping of management

messages, BS or MS masquerading, management message modification

and DoS attack.

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.

Eavesdropping

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

A

B

C

server

client

hacker

Hacker takes identity of server.

What is a DoS Attack?

The act of denying a computer user of a particular service.( user or client not able to connect to server or internet.)

It involves flooding a host until it cannot respond to legitimate traffic

Denial of service attacks

attackers make resources (server, bandwidth) unavailable to client by overwhelming resource with bogus traffic)

1. select target2. break into hosts

around the network 3. send packets toward

target from compromised hosts targe

t

Client4. Client not able to

connect to server

Other Major threats are

jamming and

data traffic modification

Jamming

Jammers block wimax use by sending out radio waves along the same frequencies that wimax use.

This causes enough interference with the communication between wimax tower and receiver client which make the service unusable.

increase the bandwidth of signals using spreading techniques, e.g. frequency hopping.

raise the power of a signal by using a more powerful transmitter, a high gain transmission antenna and a high gain receiving antenna

It is easy to detect with radio spectrum monitoring equipment.

To avoid jamming we can

Why security ? In Order to

Protect privacy

Defend against theft of service and hacking

Forgery and replay

IEEE 802.16 Security Process

Authentication the base station authenticates the client’s

digital certificate then only it grant access to the physical layer.

Authentication is needed at the starting.

WiMax basic authentication architecture, by default, employs X.509-based public key infrastructure (PKI) certificate authorization

Authentication

SS →SUBSCRIBER STATIONBS →BASE STATION

Data Key Exchange

Traffic Encryption Key (TEK): (an algorithm) Data is encrypted to form key.

TEK is generated by BS randomly

TEK is encrypted with Triple-DES (use 128 bits KEK) RSA (use SS’s public key) AES (use 128 bits KEK)

Data Key Exchange

Encryption of data Encryption is the method used to protect

the confidentiality of data flowing between a transmitter and a receiver.

Encryption involves taking a stream or block of data to be protected, called plain text, and using another stream or block of data, called the encryption key, to perform a reversible mathematical operation to generate a ciphertext(code).

The ciphertext is unintelligible and hence can be sent across the network without fear of being eavesdropped.

Data Encryption

Who is Using WiMAX Today?

US SprintNextel:Q4 WDC,

Chicago ClearwireVanu

Alltel BellSouth (Fixed) AT&T/SBC (Nevada –

fixed) 5GHz WISPs

Asia Korea: SKT Japan: KDD/NTT China: 3G allocations,

WiMAX allowance

Europe UK: BT Germany: ClearWire,

NextWave Broadcom, Deutsche Breitband Dienste

France Spain Italy

Latin America Brazil: TVA (Samsung),

Telephonica, Telmar, Brasil Telecom

Mexico: TelMex Argentina: Entrach

Conclusion (The Final Issue)

802.16 has potential to achieve great market success.

WiMAX will connect you to the internet at faster speeds and from much longer ranges

An intrusion detection system approach and firewall can be used to address some of the threats.

More research is needed in this direction.

References www.ewh.ieee.org/r4/chicago/Yu-WiMAX.pdf

http://computer.howstuffworks.com/wimax.htm

www.wimaxforum.org

http://standards.ieee.org/catalog/olis/lanman.html

THANK YOU