Database Criteria for Network Policy Chain.

Network policies that offer vital functionalities are often organized in a chain. Current practice either assumes proper policy chains as a prior or relies on simple syntax-based input-output analysis. This paper examines and addresses several difficulties with this approach --- context-dependent policy interaction, unnecessarily coupled policies, and policies that must be jointly examined, proposing database integrity constraints as a means towards a semantic-based finer solution. Built on a unified logical framework to describe and reason about policy chains, our database solution gives (1) criteria that derive correct policy chain with a more accurate estimate of policy dependency, and (2) criteria that check and obtain atomic policy, unit of policy that is proper for policy chain.