This carries the name of the currently-active member tunnel within a protection group as reported in a trap, giving the admin a human-readable answer to 'which path is my traffic on right now' without decoding an index. This matters operationally because after a failover, ongoing latency or loss complaints should be investigated against the newly active tunnel's path, not the one that was originally primary. For example, seeing active tunnel name backup-lsp-secondary-path in a recent trap tells the admin to check that specific LSP's health, not the original primary path.