Wireless LAN Security Protocols (WEP-WPA)

Wireless LAN Security Protocols (WEP/WPA) : 

Wireless LAN Security Protocols (WEP/WPA) Eng.Fawaz Fawaz.2009@hotmail.com Ksu-sa

Outline : 

security requirements. Wi-Fi. What is WEP. What is WPA. 802.11i. Comparison. Hacking . Summary. References. Outline

security requirements : 

Confidentiality - Messages sent must be encrypted. Authenticity - Origin of messages received must be verified. Integrity - Integrity of messages received must be verified. access control - Access for legitimate entities only. security requirements

Wi-Fi : 

Wi-Fi is wireless communication technology Wi-Fi

802.11 standers : 

802.11 standers

Cont. Wi-Fi : 

Cont. Wi-Fi

What is WEP : 

WEP –( Wired Equivalent Privacy) - part of the IEEE 802.11 specification Goal - make the Wi-Fi network at least as secure as a wired LAN. - Encrypt data transmitted to prevent the attackers from getting the information or change it. Services - access control to the network. - message confidentiality. - message integrity and authenticity. What is WEP

How WEP works : 

WEP uses encryption algorithm called RC4 The key divided in two parts There are two kinds of WEP 1)WEP 64 (40 bit + 24 bit). 2)WEP 128(104 bit + 24 bit). How WEP works

Example : 

KSU K=6Bh, S=73h, U=75h Plaintext 01101011 01110011 01110101 key stream 01101100 10010111 01101111 Cipher text 00000111 11100100 00011010 Example

The reason of Transition to WPA : 

The same IV can be used more than once. The secret key is common in WEP. The key that WEP uses is short . Most users usually do not change their keys. The reason of Transition to WPA

What is WPA : 

WPA –(Wi-Fi Protected Access). WPA use the TKIP and depends on RC4. The key in WPA consist of 128 bit and 48 bit for initial victor. What is WPA

TKIP : 

TKIP is a security protocol used in the IEEE 802.11 wireless networking standard. TKIP was a solution  to replace WEP without requiring the replacement of legacy hardware. TKIP implement three new security features TKIP

Cont. TKIP : 

First, TKIP implements a key mixing function. Second, WPA implements a sequence counter to protect against replay attacks.  Finally, TKIP implements a 64-bit message integrity check named MICHAEL. Cont. TKIP

TKIP Design : 

TKIP Design

802.11i : 

Also known as WPA 2. WPA addressed problems with WEP, but still had room for improvement. 802.11i is still being formalized. Implements new encryption algorithm. No use of RC4. 802.11i

802.11i : 

Uses Advanced Encryption Standard algorithm (AES) Variable key sizes of 128, 192 and 256 bits. Much harder to decrypt than WPA or WEP. Not compatible with today’s devices Requires new chip sets. 802.11i

comparison between protocols : 

comparison between protocols

Hacking tutorial : 

Hacking tutorial

Summary : 

security has always been considered important for Wi-Fi. WEP is weak against security attacks. TKIP provides a quick way to upgrade firmware and fix many of the flaws => WPA WAP2 use AES encryption and message integrity check but requires new hardware. Summary

References : 

[1] Lee Barken ,”How Secure Is Your Wireless Network? Safeguarding Your Wi-Fi LAN”, Prentice Hall PTR ,2003. [2] Matthew Gast ,” 802.11 Wireless Networks: The Definitive Guide”, O'Reilly, 2002. [3] www. wikipedia.org [4] www.howstuffworks.com References

Thank You : 

Thank You