Redactor: Reconcile Network Control with Declarative Control Programs in SDN

With SDN control programs from multi-domains configuring the network, it is inevitable that control programs make conflicting control decisions, which probably lead to misconfiguration or performance degradation. Existing control coordination approaches either compose control programs to derive consistent solutions jointly or examine the generated rules of each control program to ensure they are consistent. However, the former is usually of great complexity and hard to be conducted automatically, and the latter probably results in suboptimal solutions due to the independent execution of control programs. Moreover, these approaches all fail to consider the control utility of control programs. In this paper, we propose Redactor to optimize the consistency and utility of network control in an automatic and dynamic manner. To make network control consistent, we implement SDN control programs with declarative language Prolog, and compose control programs automatically to execute together to make consistent decisions. When conflicts occur, we use a heuristic approach to compromise a subset of control programs to maximize the control utility. We compare Redactor with the static priority mechanism and Athens [1], and the results show that Redactor always satisfies more control objectives to achieve better control consistency and utility.