What is the main role of the Message Integrity Check in WPA2?

The primary purpose of a Message Integrity Check (MIC) in WPA2 is to ensure data integrity. This mechanism is crucial for verifying that the data received over the network has not been tampered with during transmission. When data packets are sent, the MIC adds a cryptographic checksum to them. The receiving device can then use this checksum to confirm that the packet has not been altered. If the received checksum does not match the one calculated by the receiving party, it indicates that the data might have been corrupted or intentionally altered during transmission, triggering appropriate error handling measures.

This focus on data integrity helps protect against man-in-the-middle attacks and other types of data manipulation that could compromise the security of the transmitted information. While other aspects like user authentication and encryption play significant roles in the overall security framework of WPA2, the specific function of the Message Integrity Check is exclusively focused on verifying that data maintains its intended state from sender to receiver.