What is Virtual Routing and Forwarding (VRF)?

Virtual Routing and Forwarding (VRF) is a technology included in IP network routers that allows multiple instances of a routing table to exist in a router and work simultaneously. This increases functionality because it allows network paths to be segmented without the use of multiple devices. Because traffic is automatically segregated, VRF also increases network security and can eliminate the need for encryption and authentication. Internet Service Providers (ISPs) often take advantage of VRF in order to create separate Virtual Private Networks (VPNs) for customers. Therefore the technology is also referred to as VPN routing and forwarding.

VRF acts like a logical router, but while a logical router can include many routing tables, a VRF instance uses only a single routing table. In addition, VRF requires a forwarding table that designates the next hop for each data packet, a list of devices that can be called upon to forward the packet, and a set of rules and routing protocols that govern how the packet is forwarded. These tables prevent traffic from being forwarded outside a specific VRF path and also keep out traffic that must remain outside the VRF path.