A History of WEP The Ups and Downs of Wireless Security

Wireless Communication Beginnings  Early Cordless Phones and Cell Phones  Used same idea as Walkie-Talkies  Anyone with a “Scanner” could easily eavesdrop on calls  Used a Spread-Spectrum algorithm to defeat the traditional “Scanner”

The Standard  Defines wireless communications protocols  b, g, n common wireless network protocols  Similar to early Cell Phones and Cordless Phones at the start – no real protection  Can easily find out network names and connect to them  Invent of War Driving!

Early Security Attempts  Open Access to Networks – Solution?  Filter the “unique” MAC address of the wireless cards  Problem?  Keep a large list of EVERY network card that can have access  No real authentication or check takes place  MAC addresses can be “spoofed”

Introducing WEP  W.E.P. – Wired Equivalent Privacy  Introduced in September of 1999  First real attempt at securing open wireless networks  Attempted to make the network as confidential as a traditional wired network  Originally used a 40-bit security key, later expanded to 104-bits, and 232-bits

A Look At WEP  IV – Initialization Vector (24-bits)  Key Selected by User  Combined to create a seed to generate the keystream

All Secured Sir…….  RC4 is a popular cipher used in many security applications  Problem: RC4 is a stream cipher  Keystream cannot be reused or you can get back the message  24-bit IV has a 50% chance of repeating on a busy network after 5000 IVs generated  Can also capture packets an replay them: poor authentication

Demonstration Time

After WEP  WPA created to use existing hardware  Fixes many of the downfalls of WEP  Not without its own problems  Uses a password to generate keys  Dictionary attack  TKIP Algorithm used has flaws  WPA2 developed to fix WPA  Made before WPA flaw discovered