WEP, or Wired Equivalent Privacy, was part of the original Wi-Fi standard, using the RC4 encryption cipher, but it quickly proved to have major flaws. WPA, or Wi-Fi Protected Access, was introduced as part of the draft 802.11i standard and rushed into use when WEP’s weaknesses became clear. WPA2 is the final version, based on the completed 802.11i standard, with mandatory 128-bit encryption using the strong Advanced Encryption Standard cipher. WPA and WPA2 can be split into subtypes based on how encryption keys are created and shared, which impacts both joining the network and overall security. WPA-Personal, or pre-shared key, uses a passphrase of 8 to 63 ASCII characters manually given to each authorized user, making it great for small networks if the password is strong. WPA-Enterprise, also known as 802.1x mode, requires clients to authenticate with an external server, typically RADIUS-based, using a username and password. WPS, or Wi-Fi Protected Setup, was designed to simplify network access management for non-technical home users.