Segmented proactive flow rule injection for service chaining using SDN

Service chaining is one of the challenges in network function virtualization (NFV), where a sequence of middleboxes apply their service to particular traffic. The challenge of service chaining is that a middlebox may alter the content of packet headers; thus, the context of service chaining for particular traffic gets lost. This paper proposes Segmented Proactive Flow Rule Injection (SPFRI) using Software Defined Networking (SDN). SPFRI maintains the consistency of service chain even though one or more middleboxes may alter the packets at both outbound and inbound directions of a flow. The network configuration of middleboxes must be appropriately set to make them perform in the service chain. The significant benefits of the proposed SPFRI are as fallows: 1) no requirement of modifying to the middlebox operating system or software, 2) longer and more chains and 3) friendliness to non-SDN switches. This paper details the segmentation of the service chain and calculates the required number of flow rules. We also discuss the performance of SPFRI and a realistic approach to practical implementation.