MPLS overview
Multiprotocol Label Switching (MPLS) enables connection-oriented label switching on connectionless IP networks. It integrates both the flexibility of IP routing and the level of simplicity of Layer 2 switching.
MPLS has the following advantages:
MPLS forwards packets according to short- and fixed-length labels, instead of Layer 3 header analysis and complicated routing table lookup, enabling highly-efficient and fast data forwarding on backbone networks.
MPLS resides between the link layer and the network layer. It can operate over various link layer protocols (for example, PPP, ATM, frame relay, and Ethernet), provide connection-oriented services for various network layer protocols (for example, IPv4, IPv6, and IPX), and operate with mainstream network technologies.
MPLS is connection-oriented and supports label stack. It can be used to implement various functions, such as VPN, traffic engineering, and QoS.