MPLS Technology
Routers or switches that handle MPLS and IP are known as Label Switch Routers (LSR’s)
LSR’s at the edge of MPLS networks are sometimes referred to as Label Edge Routers (LER’s)
- Ingress LER’s are responsible for classifying unlabelled IP packets and appending the appropriate label.
- Egress LER’s are responsible for removing the label and forwarding the unlabelled IP packet towards its destination.
All IP packets that follow the same path through the MPLS network and receive the same treatment at each node are known as a Forwarding Equivalence Class (FEC).