  This manuscript aims to generate a secret key for a PHY layer to evaluate the
channel characteristics in wireless communications. An algorithmic approach is
adopted for multimedia encryption to generate a secret key between two entities
communicating with each other in a real time simulation environment such as
MATLAB. Two classes of PHY key generation schemes are analyzed for designing
the algorithm such as received-signal-strength-based and channel- phase-based
protocols. We present a performance comparison of them in terms of key
disagreement probability, key generation rate, key bit randomness, scalability,
and implementation issues.
