Describe the function of 802.11i in wireless security.
802.11i is a standard that defines security mechanisms for wireless networks. It is an amendment to the IEEE 802.11 standard, which is widely used for wireless local area networking (WLAN). 802.11i is specifically focused on enhancing the security features provided by its predecessor, WEP (Wired Equivalent Privacy), which was found to be vulnerable to various attacks.
The primary function of 802.11i is to improve the security of wireless networks through the implementation of robust encryption and authentication mechanisms. Here are some key features and functions of 802.11i:
- Enhanced Encryption with Advanced Encryption Standard (AES): 802.11i replaces the insecure WEP encryption with the more robust Advanced Encryption Standard (AES). AES is a symmetric encryption algorithm that provides a higher level of security compared to the outdated WEP.
- Key Management and Pairwise Transient Key (PTK): 802.11i introduces a new key hierarchy, including a Pairwise Transient Key (PTK). The PTK is dynamically generated for each pairwise connection between a client and an access point. This dynamic key management enhances security by minimizing the risk associated with using static keys.
- Authentication and 802.1X: 802.11i supports the use of the 802.1X standard for port-based network access control. This allows for stronger authentication methods, such as EAP (Extensible Authentication Protocol), to be used in conjunction with the wireless network.
- Pre-Shared Key (PSK) and Robust Security Network (RSN): 802.11i includes a pre-shared key (PSK) mode for simpler network setups, but it still employs advanced security measures within this mode. The complete security suite defined by 802.11i is often referred to as Robust Security Network (RSN).
- Secure Key Distribution using 4-Way Handshake: 802.11i utilizes a 4-Way Handshake mechanism to securely distribute keys between the client and the access point. This ensures that the encryption keys are established in a secure manner, reducing the risk of key compromise.
By incorporating these features, 802.11i significantly enhances the security of wireless networks, making them more resistant to various attacks and providing a higher level of confidentiality and integrity for data transmission. It is important for organizations and individuals to use WPA2 (Wi-Fi Protected Access 2) or later, which incorporates the security features defined by 802.11i, to ensure a secure wireless communication environment.