Privacy-Preserving Audit and Extraction of Digital Contents

Privacy-Preserving Audit and Extraction of Digital Contents Mehul A. Shah, Ram Swaminathan, Mary Baker HP Laboratories, Palo Alto HPL-2008-32R1 April 30, 2008* auditing, storage, A growing number of online services, such as Google, Yahoo!, and digital preservation, Amazon, are starting to charge users for their storage. Customers often storage outsourcing, use these services to store valuable data such as email, family photos and privacy, security videos, and disk backups. Today, a customer must entirely trust such external services to maintain the integrity of hosted data and return it intact. Unfortunately, no service is infallible. To make storage services accountable for data loss, we present protocols that allow a third-party auditor to periodically verify the data stored by a service and assist in returning the data intact to the customer. Most importantly, our protocols are privacy-preserving, in that they never reveal the data contents to the auditor. Our solution removes the burden of verification from the customer, alleviates both the customer’s and storage service’s fear of data leakage, and provides a method for independent arbitration of data retention contracts. Internal Accession Date Only Approved for External Publication © Copyright 2008 Hewlett-Packard Development Company, L.P. Privacy-Preserving Audit and ...