Wireless Security is the security mechanism implemented in Wi-Fi Wireless network to protect it from un-authorized access performed by attackers. IEEE 802.11i is the security standard amendment for IEEE 802.11 wireless standard. Wired Equivalent Privacy (WEP) was the initial security algorithm used in IEEE 802.11. WEP was vulnerable and exploitable. Wi-Fi Alliance brought in WPA (Wi-Fi Protected Access) to address the security issues of WEP which was an intermediate arrangement till IEEE 802.11i standard was brought with WPA2 that had strong security algorithms and later WPA3 which had much stronger security built-in into IEEE 802.11.
WEP is part of IEEE 802.11 standard that provided confidentiality on the Wi Fi wireless network, so that they attackers can’t eavesdrop the data flowing on the wireless network. WEP used Rivest Cipher 4 (RC4) encryption algorithm for encrypting the data. CRC-32 (Cyclic Redundancy Check) provided integrity check value (ICV) for that the data to make sure, nobody has changed the data in the transit. WEP used shared secret for all users on the wireless network. An Initial Vector or Initialization Vector (IV) is a random or pseudorandom data used to ensure that a cryptographic algorithm doesn’t result identical ciphertexts for identical plain text. The IV is added along the shared key into the RC4 algorithm. As the shared key was shared to endpoints in the WI FI network and IV was short, it was easy to compromise and the shared key by capturing and cracking the multiple encrypted packets sent on the WI FI network. Once the shared key is cracked, the whole wireless network is compromised.
Wi-Fi Protected Access (WPA) was an intermediate measure to address the security issues of WEP. WPA used Temporal Key Integrity Protocol (TKIP) which used RC4 per packet keying and Message Integrity Check (MIC). These made WPA to provide better security compared to WEP but still was vulnerable.
Wi-Fi Protected Access 2 (WPA2) was the actual security standard implemented by IEEE 802.11i for the Wi Fi network. WPA2 uses Counter Mode Cipher Block Chaining Message Authentication Code (CCMP) which is based on AES that provides encryption and message integrity check that addresses the vulnerabilities of WPA and WEP.
Wi-Fi Protected Access 3 (WPA3) was the next upgrade which used AES-256 in Galois/Counter Mode (GCM) for encryption and SHA-384 for message integrity check. This combination made WPA3 much stronger than WPA2 for the WI FI wireless network.