A communication device for performing cryptographically secured communication in a WLAN (Wireless Local Area Network) network is provided that comprises a security enhancement unit and a MAC (Medium Access Control) unit. The security enhancement unit is for encrypting plaintext data frames into encrypted data frames and/or decrypting encrypted data frames into plaintext data frames. The MAC unit is for managing communication between communication devices within the WLAN network by coordinating access to a shared wireless communication medium through which communication signals are transmitted. The security enhancement unit and the MAC unit are adapted to perform an on-the-fly encryption process and/or on-the-fly decryption process thereby exchanging the encrypted data frames without buffering the encrypted data frames after encryption or prior to decryption, respectively. The embodiments may provide an improved encryption/decryption architecture including an on-chip memory for performing on-the-fly encryption and/or on-the-fly decryption in the framework of 802.11i security enhancement.