CERIAS - Center for Education and Research in Information Assurance and Security

Skip Navigation
Purdue University - Discovery Park
Center for Education and Research in Information Assurance and Security

Secure Outsourcing of Computations

Mikhail Atallah - CERIAS /Purdue CS Department

Nov 07, 1997


The rapid growth of the Internet facilitates the outsourcing of computations, in the following sense: A customer who needs these computations done on some data but lacks the computational resources (or programming expertise) to do so, can use an external agent to perform these computations. This currently arises in many practical situations, including the financial services and petroleum services industries. The outsourcing is secure if it is done without revealing to the agent either the actual data or the actual answer to the computation. In this talk we describe how some computations can be securely outsourced in a practical sense. These include matrix multiplication, matrix inversion, solution of a linear system of equations, convolution, and sorting.

The general idea is for the customer to do some carefully designed local preprocessing of the data before sending it to the agent, and also some local postprocessing of the answer returned by the agent to extract from it the true answer. The pre- and postprocessing should not take time more than proportional to the size of the input, which is unavoidable because the customer must at least read the input once. The purpose of the preprocessing step that the customer performs locally is to ``hide'' the real data with suitably chosen noise, sending to the agent the obfuscated data. The purpose of the postprocessing is to extract from the noisy answer returned by the agent the true answer that the customer seeks.

Unless otherwise noted, the security seminar is held on Wednesdays at 4:30P.M. STEW G52 (Suite 050B), West Lafayette Campus. More information...


The views, opinions and assumptions expressed in these videos are those of the presenter and do not necessarily reflect the official policy or position of CERIAS or Purdue University. All content included in these videos, are the property of Purdue University, the presenter and/or the presenter’s organization, and protected by U.S. and international copyright laws. The collection, arrangement and assembly of all content in these videos and on the hosting website exclusive property of Purdue University. You may not copy, reproduce, distribute, publish, display, perform, modify, create derivative works, transmit, or in any other way exploit any part of copyrighted material without permission from CERIAS, Purdue University.