Kam Ho Ho

Publication Date

Spring 2013

Degree Type

Master's Project


Computer Science


Cloud storage becomes more and more popular in the recent trend since it provides various benefits over the traditional storage solutions. Along with many benefits provided by cloud storage, many security problems arise in cloud storage which prevents enterprises from migrate their data to cloud storage. These security problems induce the data owners to encrypt all their sensitive data such as social security number (SSN), credit card information, and personal tax information before they can be stored in cloud storage. The encryption approach may have strengthened the data security of cloud data, but it degrades the data efficiency because the encryption reduces the searchability of the data. Many schemes were proposed in recent researches which enable keyword search over encrypted data in cloud computing, and these schemes contain weaknesses which make them impractical when applying these schemes in real-life scenarios. In this project, we developed a system to support semantic search over encrypted data in cloud computing with three different schemes. The three schemes that we developed are “Synonym-Based Keyword Search (SBKS)”, “Wikipedia-Based Keyword Search (WBKS)”, and “Wikipedia-Based Synonym Keyword Search (WBSKS)”. Based on our experiment data, it demonstrated that the indexes created by our schemes are 95% smaller and reduced the average search time by 95% if compared to the schemes proposed previously. These improvements illustrated that our developed schemes are more practical than the former proposed schemes.