Common use of Registration Phase Clause in Contracts

Registration Phase. When userU wants to register with the server, it performs the following steps with the server. Step R1: The server verifies user U through a secure identification protocol. If U is eligible, then U chooses its password PW and a random integer a  Z * . Next, U computes h(PW a) and then sends{h(PW a) username} to the server over a secure channel. U  S : (h(PW a), username) R2: After the server receives the information from U , it computes secret information R  h(h(PW a) username)s1P .

Registration Phase. When userU wants to register with the server, it performs the following steps with the server. Step R1: The server verifies user U through a secure identification protocol. If U is eligible, then U chooses its password PW and a random integer a  ∈ Z * . Next, U computes h(PW a) and then sends{h(PW a) username} to the server over a secure channel. U  → S : (h(PW a), username) R2: After the server receives the information from U , it computes secret information R  = h(h(PW a) username)s1P username)s−1P . Step R3: The server stores R in the memory of a smart card and delivers this smart card to U in a secure channel. Then the user keeps PW and the smart card secretly for registration processes.