Mpls Network Structure; Lsp Establishment And Label Distribution - HP 10500 SERIES Configuration Manual

MPLS network structure

Figure 14 Diagram of the MPLS network structure
LSRs in the same routing or administrative domain form an MPLS domain.
An MPLS domain consists of the following types of LSRs:
Ingress LSRs receive and label packets coming into the MPLS domain.
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Transit LSRs forward packets along LSPs to their egress LERs according to the labels.
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Egress LSRs remove labels from packets and forward the packets to their destination networks.
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LSP establishment and label distribution

This section describes how MPLS sets up LSPs and distribute labels.
LSP establishment
Establishing LSPs is to bind FECs with labels on each LSR involved and notify its adjacent LSRs of the
bindings, so as to establish the LFIB on each LSR. LSPs can be manually established through configuration,
or dynamically established through label distribution protocols.
Establishing a static LSP through manual configuration:
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Static LSPs do not dynamically change in response to network topology changes, and are suitable
for small-scale, stable, and simple networks. To establish a static LSP, assign a label to the FEC on
each LSR along the packet forwarding path.
Establishing an LSP through a label distribution protocol:
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Label distribution protocols are MPLS signaling protocols. They can classify FECs, distribute labels,
and establish and maintain LSPs. Label distribution protocols include protocols designed
specifically for label distribution, such as the Label Distribution Protocol (LDP), and protocols
extended to support label distribution, such as BGP and RSVP-TE.
This chapter discusses LDP only. For more information about LDP, see "LDP."
In this document, the term "label distribution protocols" refers to all protocols for label distribution. The
term "LDP" refers to the RFC 5036 LDP.
A dynamic LSP is established in the following procedure:
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