Until now, ABAC research has been documented in hundreds of research papers, but not consolidated in book form. This book explains ABAC's history and model, related standards, verification and assurance, applications, and deployment challenges; Specialized topics-including formal ABAC history, ABAC's relationship with other access control models, ABAC model validation through analysis, verification and testing, deployment frameworks such as XACML, Next Generation Access Model (NGAC), attribute considerations in implementation, ABAC applications in SOA/workflow domains and ABAC architectures and feature sets in commercial & open source products. The combination of technical and administrative information for models, standards, and products in the book is thus intended to benefit researchers as well as implementers of ABAC systems.