Enabling efficient and protected sharing of data in cloud computing

Abstract

Cloud storage plays a vital role especially in applications such as medical files transfer and green computing where in-house data storage systems are established. In case of group-shared data, the data face both cloud-specific and conventional insider threats. Secure data sharing among a group that counters insider threats of legitimate yet malicious users is an important research issue in cloud. Protected Sharing of data in cloud should maintain: data confidentiality and integrity; access control; data sharing (forwarding) without using compute-intensive re-encryption; insider threat security; and forward and backward access control. The PrSDC methodology encrypts a file with a single encryption key. Two different key shares for each of the users are generated, with the user only getting one share. The possession of a single share of a key allows the PrSDC methodology to counter the insider threats and prevents stealing of medical files or in case of green computing online credit payment details. The other key share is stored by a trusted third party, which is called the cryptographic server.