Masking Text Data for Secure Multiparty Computation

A computer program product for textual masking for multiparty computation, the computer program product comprising:

• a non-volatile computer readable storage medium having program instructions embodied therewith, the program instructions executable by a number of processors to cause the computer to perform the steps of:
• receiving masked input data from a number of contributors, wherein the input data from each contributor has a unique contributor mask value added by that contributor;
• receiving a unique analyst mask factor for each contributor computed by an analyst as a difference between a uniform analyst mask value and the contributor mask value;
• receiving an application programming interface (API) call from the analyst to aggregate the input data from the contributors;
• adding the respective analyst mask factors to the masked input data from the corresponding contributors;
• aggregating and randomly shuffling the input data from the contributors;
• receiving and publishing computational results from the analyst based on the aggregated input data;
• removing the respective analyst mask factors from the computational results in response to API calls from the contributors, wherein computational results for each contributor are masked only by the respective contributor mask value added by that contributor;
• and
• sending the computational results to the contributors.

A system for textual masking for multiparty computation, the system comprising:

• a bus system;
• a storage device connected to the bus system, wherein the storage device stores program instructions;
• and
• a number of processors connected to the bus system, wherein the number of processors execute the program instructions to:
• receive masked input data from a number of contributors, wherein the input data from each contributor has a unique contributor mask value added by that contributor;
• receive a unique analyst mask factor for each contributor computed by an analyst as a difference between a uniform analyst mask value and the contributor mask value;
• receive an application programming interface (API) call from the analyst to aggregate the input data from the contributors;
• add a uniform broker mask value and the respective analyst mask factors to the masked input data from the corresponding contributors;
• aggregate and randomly shuffle the input data from the contributors;
• receive and publish computational results from the analyst based on the aggregated input data;
• remove the uniform broker mask value and the respective analyst mask factors from the computational results in response to API calls from the contributors, wherein computational results for each contributor are masked only by the respective contributor mask value added by that contributor;
• and
• send the computational results to the contributors.