By Sean Fisk

 Not a new technology  Inherently insecure  In recent years, increased popularity

 Symmetric key  Public key

 Only known type until 1976  Shared secret  Secure exchange

 Block cipher Fixed length Joining protocols  Stream cipher Variable length

 Public key Diffie and Hellman in 1976 Message is encrypted with public key Can only be decrypted with private key

 Computational complexity of mathematical problems  Diffie-Hellman Discrete logarithm problem  Rivest, Shamir, and Adleman (RSA) Integer factorization problem

 Public key encryption is much slower than symmetric key encryption  Diffie-Hellman Key Exchange protocol

 “The main intention of the WEP was not to provide a level of security superior to or higher than that of a wired LAN, but equivalent to it.” (Bulbul, Batmaz and Ozel)

 Rivest’s Cipher 4 (RC4) 64-bit  40-bit WEP key  24-bit Initialization Vector  Cyclic Redundancy Code (CRC)

 CRC not intended for message integrity  Key too short  Key as direct input to cipher  Initialization vector Interesting values

 Run on same hardware  Temporal Key Integrity Protocol (TKIP)  Still uses RC4 cipher 128-bit key  Message Integrity Code replaces CRC  Exstensible Authentication Protocol Uses public key encryption

 Continuation of RC4 cipher First few bytes are strongly non-random (Fluhrer, Mantin, Shamir)

 Also known as WPA2  Advanced Encryption Standard Joined with CCMP  Continues use of EAP

 Data Encryption Standard  Advanced Encryption Standard  Standardized by National Institute of Standards and Technology (NIST)

 Symmetric, block cipher  56-bit key  Feistel function  “In 1999, the Electronic Frontier Foundation’s ‘Deep Crack’ machine, in combination with distributed.net, successfully solved RSA’s DES Challenge III in 22 hours and 15 minutes.” (RSA Labs)  Triple DES

 Public competition 5 year process 15 ciphers Winner: Rijndael by Daemen and Rijmen  Symmetric, block cipher  128, 192, or 256-bit key

 End-to-end encryption  Trusted endpoints  Wireless hotspots

 Bulbul, Halil Ibrahim, Ihsan Batmaz and Mesut Ozel. "Wireless network security: comparison of WEP (Wired Equivalent Privacy) mechanism, WPA (Wi-Fi Protected Access) and RSN (Robust Security Network) security protocols  dlaverty. WPA vs WPA2 (802.11i): How your Choice Affects your Wireless Network Security.  Fluhrer, Scott, Adi Shami and Itsik Mantin. Weaknesses in the Key Scheduling Algorithm of RC4.  Masadeh, S.R., et al. "A comparison of data encryption algorithms with the proposed algorithm: Wireless security.“  National Institute of Standards and Technology. "FIPS Advanced Encryption Standard.“  RSA Labs January 2011.