MPLS (Multiprotocol Label Switching) is a routing technique that speeds up network traffic flow by directing data along predetermined paths using short label identifiers rather than longer network addresses.
How MPLS Works
In traditional IP routing, each router makes an independent forwarding decision based on the destination IP address. In MPLS, the path is predetermined, and packets are forwarded based on labels added at the edge of the MPLS network.
MPLS Labels
An MPLS label is a 20-bit identifier that represents a Forwarding Equivalence Class (FEC). Labels are stacked (MPLS label stack) to support hierarchical tunnels and VPN services.
Label Distribution Protocol (LDP)
LDP is the protocol used to establish and maintain LSPs in most MPLS networks. RSVP-TE (Resource Reservation Protocol - Traffic Engineering) is used when traffic engineering capabilities are required.
MPLS VPN Services
MPLS enables service providers to offer Layer 3 VPN and Layer 2 VPN services to customers, providing secure traffic separation while sharing the same physical infrastructure.
Traffic Engineering
MPLS TE allows network operators to control the path that traffic takes through the network, optimizing resource utilization and providing QoS guarantees for specific traffic classes.