A provable secure trusted protocol for NASD was proposed.The protocol will achieve authentication

key agreement and secure channel within two rounds among the server

the disks and the user.At the same time

the protocol could realize the platform authentication and platform integrity verification in the first round of protocol interaction

which would improve the efficiency of the protocol

and prevent the server from malicious attacks effectively.The analysis results show that the protocol is SK-secure by using CK model

which would increase the data confidentiality

integrity and no repudiation.