A VRF (Virtual Routing and Forwarding) is an isolated routing table that lives on a carrier’s edge routers (PE). Each customer has its own VRF: their routes never mix with others’, even though they share the same physical infrastructure. It is the building block of an enterprise L3 VPN (MPLS L3VPN).
Technically, isolation relies on route distinguishers and route targets; transport across the core uses MPLS labels. The buyer takeaway: “MPLS” is not a type of link, it is a core-network logic. Any carrier with a backbone “has MPLS”; real differentiation lies elsewhere — its ability to connect your sites and guarantee end-to-end quality of service.
The modern alternative, SD-WAN, moves this logic into an overlay on any Internet access — at the cost of the native guarantee.