  Attribute-based access control (ABAC) promises a powerful way of formalizing
access policies in support of a wide range of access management scenarios.
Efficient implementation of ABAC in its general form is still a challenge,
especially when addressing the complexity of privacy regulations and access
management required to support the explosive growth of social and IoT networks.
In this paper, we introduce a graph model implementation for expressing and
evaluating access policies and illustrate a sample use-case implementation over
Neo4 Graph Database. Graph databases excel at querying connected data and hence
can evaluate complex policies efficiently via graph traversal algorithms.
