Monitoring distributed collections using the Audit Control Environment (ACE)

The Audit Control Environment (ACE) is a system which provides a scalable, auditable platform that actively monitors collections to ensure their integrity over the lifetime of an archive. It accomplishes this by using a small integrity token issued for each monitored item. This token is part of a larger externally auditable cryptographic system. We will describe how this system has been implemented for a set of applications designed to run in an archive or library environment. ACE has been used for almost two years by the Chronopolis Preservation Environment to monitor the integrity of collections replicated between the three independent archive partners. During this time, ACE has been expanded to better support the requirements of this distributed archive. We will describe how ACE has been used and expanded to support the Chronopolis preservation requirements. We conclude by discussing several future requirements for integrity monitoring that have been identified by users of ACE. These include securely monitoring remote data, monitoring offline data, and scaling monitoring activities in a way that does not impact the normal operational activity of an archive.