LSP establishment

LSPs include static and dynamic LSPs.

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:

  1. A downstream LSR classifies FECs according to destination addresses.

  2. The downstream LSR assigns a label for each FEC, and distributes the FEC-label binding to its upstream LSR.

  3. The upstream LSR establishes an LFIB entry for the FEC according to the binding information.

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 4: Dynamic LSP establishment