Extending N-grid group authorization using compact encoding

In the original N-grid model for group authorization, subject groups, object groups, and access right groups are organized in partial orders based on the semantics of authorizations. The n-dimension grid encoding using the dimension theory of partial orders allows top-down incremental change of partial orders without changing their encoded representations. Authorizations are encoded by mapping all three groups consistently onto an n-dimension grid. Consistent and manageable group access control, eficient access checking, space utilization, and the ability to provide top-down incremental sub-grouping are the advantages of the original N-grid model. However, for higher dimension partial orders, the encoding scheme using dimension theory incurs increasing overhead when [he dimension of partial orders increased. In this paper, we provide a complementary solution, a new N-grid mode!, using compact encodingfor higher dimension partial orders, discuss the advantages and disadvantages of the new encoding scheme, and eva[uale its performance improvement.