A virtual private network (VPN) is a technology for using the Internet or another intermediate network to connect computers to isolated remote computer networks that would otherwise be inaccessible.
Multi-Protocol Label Switching (MPLS) was originally presented as a way of improving the forwarding speed of routers but is now emerging as a crucial standard technology that offers new capabilities for large scale IP networks.
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VPN is a network layered on top of a computer network; MPLS directs and carries data from one network node to the next. VPN use cryptographic tunnelling protocols to provide high level security; MPLS is operable between the Data Link Layer and the Network Layer.