Quantum cryptography based on Grover´s algorithm

Some cryptographic applications of quantum algorithm on many qubits system are presented. We analyze a basic concept of Grover algorithm and it´s implementation in the case of four qubits system. We show specially that Grover algorithm allows as obtaining a maximal probability to get the result. Some features of quantum cryptography and Quantum Secret-Sharing protocol based on Grover´s algorithm are also presented.