  Quantum cryptography is now considered as a promising technology due to its
promise of unconditional security. In recent years, rigorous work is being done
for the experimental realization of quantum key distribution (QKD) protocols to
realize secure networks. Among various QKD protocols, coherent one way and
differential phase shift QKD protocols have undergone rapid experimental
developments due to the ease of experimental implementations with the present
available technology. In this work, we have experimentally realized optical
fiber based coherent one way and differential phase shift QKD protocols at
telecom wavelength. Both protocols belong to a class of protocols named as
distributed phase reference protocol in which weak coherent pulses are used to
encode the information. Further, we have analyzed the key rates with respect to
different parameters such distance, disclose rate, compression ratio and
detector dead time.
