Multi Protocol Label Switching (MPLS) network, incoming packets are assigned a "label" by a "label edge router (LER)". Packets are forwarded along a "label switch path (LSP)" where each "label switch router (LSR)" makes forwarding decisions based solely on the contents of the label. At each hop, the LSR strips off the existing label and applies a new label which tells the next hop how to forward the packet.
Label Switch Paths (LSPs) are established by network operators for a variety of purposes, such as to guarantee a certain level of performance, to route around network congestion, or to create IP tunnels for network-based virtual private networks. In many ways, LSPs are no different than circuit-switched paths in ATM or Frame Relay networks, except that they are not dependent on a particular Layer 2 technology.
An LSP can be established that crosses multiple Layer 2 transports such as ATM, Frame Relay or Ethernet. Thus, one of the true promises of MPLS is the ability to create end-to-end circuits, with specific performance characteristics, across any type of transport medium, eliminating the need for overlay networks or Layer 2 only control mechanisms
Multi Protocol Label Switching (MPLS) is one of the central elements of next generation networks. It provides an IP-compatible, QoS-capable infrastructure that enables the convergence of voice, IP, ATM, Ethernet, and Frame Relay onto the same backbone network. MPLS can combine the intelligence and salability of routing with the reliability and manageability of traditional carrier networks. It is the key to scalable virtual private networks (VPNs) and end-to-end quality of service (QoS).
This course provides an in-depth study of MPLS technology, including MPLS theory and configuration, network design issues, case studies, operations, VPN, Traffic Engineering and GMPLS (Generalized MPLS).