The 802.11 standard wireless protocol and is manage by the Instituteof Electrical and Electronics Engineers (IEEE).The 802.11 standard divides all packets into three different categories: data,management, and control. These different categories are known as the packet type. Datapackets are used to carry higher-level data (such as IP packets). Management packets areprobably the most interesting to attackers; they control the management of the network.Control packets get their name from the term “media access control.” They are used formediating access to the shared medium.there are two verydifferent encryption techniques used to protect 802.11 networks: Wired EquivalencyProtocol (WEP) and Wi-Fi Protected Access (WPA). WEP is the older, extremely vulnerablestandard. WPA is much more modern and resilient. WEP networks (usually) rely on astatic 40- or 104-bit key that is known on each client. This key is used to initialize a streamcipher (RC4). Many interesting attacks are practical against RC4 in the way it is utilizedwithin WEP. These attacksare covered in Chapter 3, “Attacking 802.11 WirelessNetworks.” WPA can be configured in two very different modes: pre-shared key (orpassphrase) and enterprise mode.
