Abstract:
Software Defined Network (SDN) is new paradigm which decouples control plane and management plane from data plane which is obtained from forwarding devices. Control plane and management planes are implemented in centralized entity called controller. Data plane encompass the network devices mainly of switches which are controlled directly by the controller in order to install the forwarding rules called flow rules. Control plane in SDN has a single or multiple software application-based controllers. It communicates and commands the forwarding devices using the OpenFlow protocol. Application plane contains different applications that interact with controller to operate and manage network. Due to centralized architecture, SDN has many advantages, for example, it makes easy to control and manage the network. Second, it allows to modify the control protocol without making modifications in the forwarding devices, i.e. it allows the network to evolve the network without involving the vendors to update the hardware of the forwarding devices. Despite of numerous advantages, SDN is more prone to logical errors like loops, black holes, reachability problem, ACL policies violation and ACL policy conflicts etc. These logical problems are called network wide invariants. In this research work we proposed a technique to detect to network wide invariants due to ACL polices conflicts. Proposed method detects conflicts in ACL polices and check if there is an overlap in ACL polices and present ACL polices in a form which is much easier to travers which consequently improves the performance of network.
