The symmetria system introduces two symmetric encryption schemes namely SAHE (Symmetric Additive Homomorphic Encryption) and SMHE (Symmetric Multiplicative Homomorphic Encryption) that allow additions and multiplications over encrypted data.

These schemes can replace previous asymmetric PHE schemes such as Paillier or ElGamal. symmetria leads to smaller ciphertext size overheads and faster execution times for encryption, decryption and homomorphic operations.

This repository contains a proof-of-concept implementation of the encryption schemes SAHE and SMHE and comparisons against Paillier and ElGamal. More details about these schemes and the symmetria system can be found in out VLDB'20 paper:

Savvas Savvides, Darshika Khandelwal, Patrick Eugster
Efficient Confidentiality-Preserving Data Analytics over Symmetrically Encrypted Datasets
46th International Conference on Very Large Data Bases (VLDB'20)

Installation

You can compile this repository by running:

mvn package

This will create the jar file target/symmetria-0.1-SNAPSHOT.jar

mvn package will automatically run the junit tests provided.

You can avoid running tests during compilation by running:

mvn package -DskipTests

Usage

To run a class in the above jar use:

java -cp target/symmetria-0.1-SNAPSHOT.jar CLASS_FULL_PATH

Examples

To compare SAHE to Paillier you can run:

java -cp target/symmetria-0.1-SNAPSHOT.jar edu.purdue.symmetria.evaluate.AHEScheme

and to compare SMHE to ElGamal:

java -cp target/symmetria-0.1-SNAPSHOT.jar edu.purdue.symmetria.evaluate.MHEScheme

To run "Packed Paillier" which packs 21 plaintexts in a single ciphertext using the packing method described in the paper "T. Ge and S. Zdonik. Answering aggregation queries in system model, VLDB'07" you can run:

java -cp target/symmetria-0.1-SNAPSHOT.jar edu.purdue.symmetria.evaluate.PackedScheme

Contact

If you want to know more about our project or have questions, please contact Savvas savvas@purdue.edu.