Temporal Implications of Database Information Accountability

Information restriction controls access and renders records immutable, information accountability requires data transparency to easily and efficiently determine when a particular use is appropriate. Information accountability in the context of relational databases is associated with time in a surprising number of ways, as is summarized in this paper. Notarization and validation of a database exploit the temporal semantics of a transaction-time database. A corruption can be associated with multiple times. Forensic analysis determines the when: bounds on the corruption time, and the where: also specified in terms of time. These bounds are depicted in a two-dimensional corruption diagram, with both axes denoting time. The various kinds of corruption events are defined in terms of time. A parameter termed the regret interval has significant security and performance implications. This paper emphasizes the deep connections between time and the definition, detection, forensic analysis, and characterized extent of a database corruption within the context of information accountability.