VNS3 lets you extend your network to your cloud.
VNS3 is a hybrid overlay networking appliance. VNS3 acts as five devices in one: router, switch, firewall, VPN concentrator, protocol redistributor and scriptable SDN. VNS3 is different from other SDN and network function virualization (NFV) solutions by creating a customer controlled overlay network on top of the underlying network backbone.
How to set up a VPC with VNS3Added: 5/21/13