Abstract: Although convergent encryption has effectively solved the contradiction between encryption and deduplication, it still faces many security problems. Aiming at the problem of conventional convergence encryption vulnerable to dictionary attacks, this paper proposes a convergence encryption scheme based on Merkle Hash tree, which realizes data deduplication, strengthens the confidentiality of data and effectively avoids data dictionary attacks by performing additional cryptographic operations. To overcome the problem that convergent keys linearly increase with the number of users, key sharing mechanism is designed , which can reduce more storage space of  convergent keys.

Key words: cloud storage, data deduplication, convergence encryption, Merkle Hash tree

摘要： 收敛加密可以有效地解决数据加密和去重的矛盾，实现安全去重复，但是收敛加密仍然面临许多安全问题。针对传统的收敛加密容易遭受字典攻击的问题，提出基于Merkle哈希树的收敛加密方案实现数据去重复，通过执行额外的加密操作，加强数据的机密性，有效地避免字典攻击。为了克服传统的收敛加密方案的收敛密钥随着用户数量线性增长的问题，设计收敛密钥共享机制，进一步节省了收敛密钥的存储空间。

关键词: 云存储, 数据去重复, 收敛加密, Merkle哈希树