Abstract
The Health Information Technology for Economic and Clinical Health Act (HITECH) of 2009 encourages healthcare providers to share information to improve healthcare quality at reduced cost. Such information sharing, however, raises security and privacy concerns that require appropriate access control mechanisms to ensure Health Insurance Portability and Accountability Act (HIPAA) compliance. Current approaches such as Role-Based Access Control (RBAC) and its variants, and newer approaches such as Attribute-Based Access Control (ABAC) are inadequate. RBAC provides simple administration of access control and user permission review, but demands complex initial role engineering and makes access control inflexible. ABAC, on the other hand, simplifies initial setup but increases the complexity of managing privileges and user permissions. These limitations have motivated research into the development of newer access control models that use attributes and policies while preserving RBAC's strengths. The BiLayer Access Control (BLAC) model is a two-step method being proposed to integrate attributes with roles: an access request is checked against pseudoroles, i.e., the list of subject attributes (first layer), and then against rules within the policies (second layer) associated with the requested object. This paper motivates the BLAC approach, outlines the BLAC model, and illustrates its usefulness to healthcare information sharing environments.