Which encryption keys are used in WPA?

The encryption keys used in Wi-Fi Protected Access (WPA) are based on the TKIP (Temporal Key Integrity Protocol) and, in the case of WPA2, the AES (Advanced Encryption Standard) with CCMP (Counter Mode with Cipher Block Chaining Message Authentication Code Protocol). WPA employs 128-bit encryption keys, which provide a balance of security and performance for wireless networks.

While it is essential to have varied encryption key lengths across different protocols, WPA specifically utilizes 128-bit keys to ensure secure wireless access. This size is robust enough to provide significant resistance against brute-force attacks, which is a key consideration when securing wireless communications.

The significance of the other options lies in their application to different context scenarios, where for instance, 64-bit keys may have historical relevance in earlier or less secure encryption standards but do not apply to WPA, while options like 256-bit and 512-bit keys are associated with higher-level security protocols or applications, such as those used in VPNs or file encryptions, rather than the specific WPA standard focused on wireless security. Thus, 128-bit keys are the standard for WPA encryption, confirming the option as the correct answer.