A full lifecycle privacy protection scheme for sensitive data in cloud computing

With the rapid development of versatile cloud services, it becomes increasingly susceptible to expose users’ sensitive data into the cloud computing environment. In this paper, we propose a full lifecycle privacy protection scheme for sensitive data (FullPP), which is based on identity-based timed-release encryption (ID-TRE) algorithm and distributed hash table (DHT) network. In the FullPP scheme, we first encrypt the sensitive data into a ciphertext, which is broken up into extracted ciphertext and encapsulated ciphertext by using an extracting algorithm. Then, we leverage the ID-TRE algorithm to encrypt the decryption key and combine the key’s ciphertext with the extracted ciphertext to generate ciphertext shares. Finally, we distribute the ciphertext shares into the DHT network and store the encapsulated ciphertext into cloud servers. To recover the plaintext of the sensitive data, sufficient ciphertext shares, ID-TRE private key and the encapsulated ciphertext should be obtained during the lifecycle of the sensitive data. As a result, FullPP is able to provide full lifecycle privacy protection for users’ sensitive data by making it unreadable before a predefined time and automatically destructed after expiration. Security analysis indicates that the FullPP scheme is able to resist against both traditional attacks on the cloud servers and Sybil attacks on the DHT network. Experiment result shows that the FullPP scheme proposed by us is more effective and efficient than other existing schemes.