MPLS LSP Connectivity Test When the Initiator Address is Unknown

摘要

The present disclosure provides for carrying reachability information in an echo request message and/or an echo reply message, which can be used to reach an initiator when the initiator's address is unknown. An echo request message includes an FEC (forwarding equivalence class) stack that identifies a label switched path (LSP). The echo request message is received by a label switching routing element (LSR) on the LSP, and the echo request is originated by an initiator. In response to a detection that the FEC stack changes at the LSR, a segment reachability (SR) sub-TLV (type-length-value) element can be generated, where the SR sub-TLV includes reachability information that can be used to reach the initiator, and the reachability information includes an incoming label allocated by the LSR to reach the initiator.

主权项

1. A method comprising:
receiving an echo request message, wherein
the echo request message comprises an FEC (forwarding equivalence class) stack that identifies a label switch path (LSP),the echo request message is received by a label switching routing element (LSR) on the LSP, andthe echo request is originated by an initiator; detecting whether the FEC stack changes at the LSR; and in response to a detection that the FEC stack changes at the LSR,
generating a segment reachability (SR) sub-TLV (type-length-value) element, wherein
the SR sub-TLV element comprises reachability information that can be used to reach the initiator, andthe reachability information comprises an incoming label allocated by the LSR to reach the initiator.