A Secure Code Based Cloud Storage System Using Proxy Re-Encryption Scheme in Cloud Computing

Cloud computing is a model for enabling convenient, on demand network access to a shared pool of computing resources. The cloud storage system consists of a collection of storage servers and key servers. Storing data in a third party cloud system causes serious concern on data confidentiality, so a user divides the data into blocks, encrypts and stores them in various storage servers. The storage server encodes the data using erasure codeword symbol. When the sender wants to share his messages, he sends a re-encryption key to the storage server. The storage server re-encrypts the original codeword symbol into a re-encrypted codeword symbol. The re-encryption scheme is integrated with a secure decentralized erasure code so that a secure distributed system is designed. The proxy re-encryption scheme supports the encoding operations over encrypted messages as well as forwarding operations. The key server retrieves re-encrypted codeword symbols and performs partial decryption so that the receiver combines the blocks to retrieve the data.