The State of the Art in Intrusion Prevention and Detection

207Encrypted Ranked Proximity and Phrase Searching in the Cloud

this document for headlining. A malicious attacker with access to the cloud’s database could know

that α contains the encrypted keywords and likely contains them in close proximity. This informa-

tion can be used by itself or be used in conjunction with other leaked data (such as a specic key-

word’s encrypted values) to further reduce the security of our system. While papers [19,29,30] have

proposed workarounds, leaking a user’s results and search patterns is a problem with almost every

encrypted search method [20,21]; we can reduce the severity of it in ours by implementing headlin-

ing and encrypting in parts.

Encrypting in parts works as follows. Each document is split into a ...