The Error Checking function provides statistically acceptable assurance that no components of the AIP are corrupted during any internal Archival Storage data transfer. This function requires that all hardware and software within the archive provide notification of potential errors and that these errors are routed to standard error logs that are checked by the Archival Storage staff. The PDI Fixity Information provides some assurance that the Content Information has not been altered as the AIP is moved and accessed. Similar information is needed to protect the PDI itself. A standard mechanism for tracking and verifying the validity of all data objects within the archive may also be used. For example, CRCs could be maintained for every individual data file. A higher level of service, such as Reed-Solomon coding to support combined error detection and correction, could also be provided. The storage facility procedures should provide for random verification of the integrity of data objects using CRCs or some other error checking mechanism.