Stochastic Timing Analysis of the AES Cipher Algorithm over a Correlated Fading Channel

Broadcast and multicast services (BCMCS) in CDMA2000 wireless telecommunications networks restrict high- quality multimedia services to their intended recipients by encrypting content. The air specification of BCMCS includes the advance encryption standard (AES) block cipher in the security layer of the broadcast protocol suite. We surveyed the AES block cipher algorithm and characterized the time it requires. We also profiled the execution time of each transformation that comprises the AES cipher. Drawing on these results, we proposed a analytic model that can predict the time required to decrypt encrypted contents at a mobile by considering cross-layer information, such as the characteristics of error control using Reed-Solomon coding in the MAC layer and varying conditions of the fading channel in the physical layer. This model will enable us to estimate the buffer size required to ensure seamless multimedia services.