LSP Ping Test

The NQA label-switched paths (LSP) ping test checks the reachability of Label Distribution Protocol (LDP) LSPs or traffic engineering (TE) LSPs.

Figure 1 shows the process of an LSP ping test:

1. The source (PE-A) constructs a Multiprotocol Label Switching (MPLS) Echo Request packet whose destination IP field is an IP address on the address block 127.0.0.0/8. The source then searches for the corresponding Label Distribution Protocol (LDP) LSP based on the configured remote label switching router (LSR) ID. The source forwards the packet through that LDP LSP in the MPLS domain. For a TE LSP, the packet can be sent from a tunnel interface and then forwarded along a specified constraint-based routed LSP (CR-LSP).

2. The destination (PE-B) egress monitors port 3503 and sends an MPLS Echo Reply packet to the source.

3. The source receives the MPLS Echo Reply packet and calculates the time taken for communication between the source and the destination.

Figure 1 Network for LSP ping test

LSP ping test results and historical records are collected in test instances. You can run commands to view the test results and historical records.