Design Challenges for High Performance, Scalable NFV Interconnects

Software-based network functions (NFs) have seen growing interest. Increasingly complex functionality is achieved by having multiple functions chained together to support the required network-resident services. Network Function Virtualization (NFV) platforms need to scale and achieve high performance, potentially utilizing multiple hosts in a cluster. Efficient data movement is crucial, a cornerstone of kernel bypass. Moving packet data involves delivering the packet from the network interface to an NF, moving it across functions on the same host, and finally across yet another network to NFs running on other hosts in a cluster/data center. In this paper we measure the performance characteristics of different approaches for moving data at each of these levels. We also introduce a new high performance inter-host interconnect using InfiniBand. We evaluate the performance of Open vSwitch and the Open Net VM NFV platform, considering a simple forwarding function and Snort, a popular intrusion detection system.