10-05-2013, 04:28 PM
Proxy Re-Encryption Scheme For Cloud Storage System
Proxy Re-Encryption.pptx (Size: 90.47 KB / Downloads: 42)
ABSTRACT
A cloud storage system, consisting of a collection of storage servers, provides long-term storage services over the Internet. Storing data in a third party’s cloud system causes serious concern over data confidentiality. General encryption schemes protect data confidentiality, but also limit the functionality of the storage system because a few operations are supported over encrypted data. Constructing a secure storage system that supports multiple functions is challenging when the storage system is distributed and has no central authority. The distributed storage system not only supports secure and robust data storage and retrieval, but also lets a user forward his data in the storage servers to another user without retrieving the data back.. Our method fully integrates encrypting, encoding, and forwarding. We analyze and suggest suitable parameters for the number of copies of a message dispatched to storage servers and the number of storage servers queried by a key server.
EXISTING SYSTEM
General encryption schemes protect data confidentiality, but also limit the functionality of the storage system because a few operations are supported over encrypted data. Storing data in a third party’s cloud system causes serious concern on data confidentiality.
In the existing system, constructing a secure storage system that supports multiple functions is challenging when the storage system is distributed and has no central authority.
DISADVANTAGES OF EXISTING SYSTEM
There are three problems in the above straightforward integration of encryption and encoding. First,
The user has to do most computation and the communication traffic between the user and storage servers is high.
The user has to manage his cryptographic keys. If the user’s device of storing the keys is lost or compromised, the security is broken.
Finally, besides data storing and retrieving, it is hard for storage servers to directly support other functions.
For example, storage servers cannot directly forward a user’s messages to another one. The owner of messages has to retrieve, decode, decrypt and then forward them to another user.
PROPOSED SYSTEM
In the proposed system, we propose a threshold proxy re-encryption scheme and integrate it with a decentralized erasure code such that a secure distributed storage system is formulated.
By using the threshold proxy re-encryption scheme, we present a secure cloud storage system that provides secure data storage and secure data forwarding functionality in a decentralized structure.
ADVANTAGES OF PROPOSED SYSTEM
The threshold proxy re-encryption scheme supports encoding, forwarding, and partial decryption operations in a distributed way. To decrypt a message of k blocks that are encrypted and encoded to n codeword symbols, each key server only has to partially decrypt two codeword symbols in our system. Moreover, each storage server independently performs encoding and re-encryption and each key server independently perform partial decryption. Our storage system and some newly proposed content addressable file systems and storage system are highly compatible. Our storage servers act as storage nodes in a content addressable storage system for storing content addressable blocks.