Abstract: The data assured deletion is a spot for cloud storage security．The data assured deletion approach which is distributed is not account for nodes’ trust in the DHT,so it will lead user can’t access data before the deadline．To solve this problem,a data assured deletion scheme based on trust value for cloud storage (DDTV) was proposed．The core of DDTV is evaluation of DHT nodes and choosing high nodes to store key shares．The dynamic property of DHT network makes keys to be deleted periodically,causing the sensitive data in cloud computing to be automatically destroyed after the expiration time．Compared with the data assured deletion approach which is distributed,the difference is that keys are pushed to DHT network based on trust value after partitioned by secret sharing scheme,especially the nodes which have high trust value will be chosen in the DDTV．This difference improves the possibility of decrypting the data before the deadline．The experiment results show that the method can not only identify the malicious node in the DHT,but also improve the success rate of key share extract．The high rate of key share extract can increase the rate of user access to sensitive data in the authorized time.

Key words: Cloud storage,Data deletion,Node trust value,Data confidentiality