VFP: A Virtual Switch Platform for Host SDN in the Public Cloud (Article version)

The Virtual Filtering Platform (VFP) is a cloud-scale programmable virtual switch providing scalable SDN policy to one of the world’s largest clouds, Microsoft Azure. It was designed from the ground up to handle the programmability needs of Azure’s many SDN applications, the scalability needs of deployments of millions of servers, and to deliver the fastest virtual networks in the public cloud to Azure’s VMs through hardware offloads. We, the VFP team, describe here our goals and motivations in building VFP, VFP’s design, and lessons we learned from production deployments. We also compare our design with that of other popular host SDN technologies such as OpenFlow and Open vSwitch (OVS) to show how our constraints in the public cloud can differ from those of popular open source projects. We believe these lessons can benefit the SDN community at large.