A low latency service function chain with SR-I/OV in software defined networks

A network flow is required to be processed by multiple network functions such as PGW and SGW in mobile networks as a service function chain (SFC). Compared to hardware-based network functions, virtualized network functions are more flexible for deployment. Software defined network (SDN) provides a centralized network architecture to manage network resources and route the network flow among network functions in sequence and virtual machines are leveraged to deploy the network functions as network function virtualization (NFV). However, currently the performance of NFV suffers from I/O latency because packet processing causes lots of interrupts that decreases CPU utilization. To address the I/O latency issue, SR-I/OV network card is designed to replace OpenvSwitch in host machines to reduce the system interrupts. However, SR-I/OV is not compatible with existing SDN system, which is an important component in future 5G networks. Therefore, we propose an integrated architecture called the low latency service function chain from a wider perspective in system design to overcome main defects described above. We modify appropriate components in SR-I/OV driver and OpenvSwitch to dramatically reduce packet processing latency in SFC composed by several VNFs. Moreover, our design is compatible with SDN environment and benefited by central control.