Lsp Establishment - HP 10500 Series Configuration Manual

Ingress LSR—Ingress LSR of packets. It labels packets entering into the MPLS network.
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• Transit LSR—Intermediate LSRs in the MPLS network. The transit LSRs on an LSP forward packets to
the egress LSR according to labels.
Egress LSR—Egress LSR of packets. It removes labels from packets and forwards the packets to their
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destination networks.

LSP establishment

LSPs include static and dynamic LSPs.
Static LSP
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To establish a static LSP, you must configure an LFIB entry on each LSR along the LSP. Establishing
static LSPs consumes fewer resources than establishing dynamic LSPs, but static LSPs cannot
automatically adapt to network topology changes. Therefore, static LSPs are suitable for
small-scale networks with simple, stable topologies.
Dynamic LSP
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Dynamic LSPs are established by label distribution protocols (also called MPLS signaling protocols).
They classify FECs, distribute FEC-label mappings, 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
MP-BGP and RSVP-TE.
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 steps:
A downstream LSR classifies FECs according to destination addresses.
1.
The downstream LSR assigns a label for each FEC, and distributes the FEC-label binding to its
2.
upstream LSR.
The upstream LSR establishes an LFIB entry for the FEC according to the binding information.
3.
After all LSRs along the LSP establish an LFIB entry for the FEC, a dynamic LSP is established for the
packets of this FEC.
Figure 10 Dynamic LSP establishment
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