HPE FlexNetwork 5510 HI Series, Руководство по настройке Mpls

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LSR
A router that performs MPLS forwarding is a label switching router (LSR).
LSP
A label switched path (LSP) is the path along which packets of an FEC travel through an MPLS
network.
An LSP is a unidirectional packet forwarding path. Two neighboring LSRs are called the upstream
LSR and downstream LSR along the direction of an LSP. In
Figure 2 , LSR B is the downstream LSR
of LSR A, and LSR A is the upstream LSR of LSR B.
Figure 2 Label switched path
LFIB
The Label Forwarding Information Base (LFIB) on an MPLS network functions like the Forwarding
Information Base (FIB) on an IP network. When an LSR receives a labeled packet, it searches the
LFIB to obtain information for forwarding the packet, such as the label operation type, the outgoing
label value, and the next hop.
Control plane and forwarding plane
An MPLS node consists of a control plane and a forwarding plane.
•
Control plane —Assigns labels, distributes FEC-label mappings to neighbor LSRs, creates the
LFIB, and establishes and removes LSPs.
•
Forwarding plane —Forwards packets according to the LFIB.
MPLS network architecture
Figure 3 MPLS network architecture
An MPLS network has the following types of LSRs:
•
Ingress LSR —Ingress LSR of packets. It labels packets entering into the MPLS network.
LSR A
LSR B
LSR C
LSR D
LSP
LSP
LSP
Ingress LSR
LSP
Egress LSR
Transit LSR
IP network
IP network
MPLS network