Multiprotocol Label Switching (MPLS) is a routing technique used in telecommunications networks that directs data from one node to the next based on labels rather than network addresses. MPLS assigns labels to each data packet, controlling the path the packet follows, and it works in conjunction with the Internet Protocol (IP) and its routing protocols. MPLS is a scalable and protocol-independent solution that provides dynamic, transparent virtual networks with support for traffic engineering, the ability to transport layer-3 (IP) VPNs with overlapping address spaces, and support for layer-2 pseudowires using Pseudowire Emulation Edge-to-Edge (PWE3) that are capable of transporting a variety of transport payloads (IPv4, IPv6, ATM, Frame Relay, etc.) .
MPLS is used by organizations that have multiple remote branch offices across the country or around the world that need access to a data center or applications at the organization’s headquarters or another branch location. MPLS is a Layer 2.5 technology, meaning it falls between Layer 2 (Data Link) and Layer 3 (Network) of the OSI seven-layer hierarchy. MPLS routes traffic based on predetermined “labels” rather than source and destination addresses, and it separates forwarding mechanisms from routing mechanisms, which helps boost the speed of network traffic.
MPLS is highly versatile and unifying, as it provides mechanisms to carry a multitude of traffic, including Ethernet traffic, and it supports traffic separation and the creation of virtual private networks (VPNs), virtual private local area network services, and virtual leased lines. MPLS is not tied to any particular protocol, and it can handle multiple network protocols.
In summary, MPLS is a routing technique that uses labels to direct data from one node to the next, providing dynamic, transparent virtual networks with support for traffic engineering and VPNs. It is used by organizations with multiple remote branch offices and is highly versatile and unifying, providing mechanisms to carry a multitude of traffic.
