Key Update Mechanism for Network Storage of Encrypted Data
Dai Watanabe, Masayuki Yoshino · 2013
Cryptography is now popularized and is widely used anywhere for many aims such as data confidentiality and integrity. The key of cryptography has a lifetime, thus a key update issue is well-known to be one of hard problems in practice. According to the National Institute of Standards and Technology SP 800-57, the lifetime of the cryptographic key and the lifetime of encrypted data are strictly limited. In other words, the encrypted data is required to be periodically re-encrypted. In this paper, we point out that this key update issue is now crucial in network storage and propose a key update mechanism efficiently reducing the communication and computation cost of re-encryption.