Benchmarking Encrypted Data Storage in HBase and Cassandra with YCSB

Using cloud storage servers to manage large amounts of data has gained increased interest due to their advantages (like availability and scalability). A major disadvantage of cloud storage providers, however, is their lack of security features. In this article we analyze a cloud storage setting where confidentiality of outsourced data is maintained by letting the client encrypt all data records before sending them to the cloud storage. Our main focus is on benchmarking and quantifying the performance loss that such a cloud storage system incurs due to encrypted storage. We present results based on a modification of the Yahoo! Cloud Serving Benchmark using the AES implementation of the Bouncy Castle Java Cryptography Provider for the encryption and decryption steps. The results show that for single read and write operations the performance loss is acceptable (even for stronger encryption with 256 bit keylength) while for range scans the impact can be quite severe.