  Several quantum protocols for data security having been proposed and, in
general, they have different optical implementations. However, for the
implementation of quantum protocols in optical networks, it is highly
advantageous if the same optical setup can be used for running different
quantum communication protocols. In this direction, here we show an optical
scheme that can be used for quantum key distribution (QKD), quantum secure
direct communication (QSDC) and quantum secret sharing (QSS). Additionally, it
is naturally resistant to the attack based on single-photon detector blinding.
At last, we show a proof-of-principle experiment in 1 km optical fiber link
that shows the feasibility of the proposed scheme.
