Analysis of some keyword search schemes in encrypted data

With remote storage systems, a user may store his data in the encrypted form at the remote storage server to preserve confidentiality. Later, the user wants to receive his data securely through an untrusted network. The user does not want to receive all of the stored data but the data related to specific words, to reduce the communication overload in the network. In this case, we need secure and efficient keyword search schemes over the encrypted data. In the paper, we show that the keyword search schemes suggested by Byun et al. and Ballard et al. do not provide semantic security which is the most important security requirement for the keyword search schemes.