Diffserv traffic engineering compliant backup paths for fast reroute protection in MPLS

A method, implemented in a Point of Local Repair (PLR) network element, comprising:

• receiving a PATH message for a Label Switched Path (LSP) tunnel in a Multiprotocol Label Switching (MPLS) network with a specified DiffSery Traffic Engineering (DSTE) Class Type;
• processing a FAST REROUTE object in the PATH message which indicates Facility Bypass is desired;
• determining the DSTE Class Type based on the PATH message;
• storing the DSTE Class Type for the LSP tunnel to ensure a Facility Bypass tunnel used for the LSP tunnel supports the specified DSTE Class Type;
• and
• performing one of
• (1) receiving a second PATH message for a second LSP tunnel with a second FAST_REROUTE object including a second DSTE Class Type that is the same as the specified DSTE Class Type, and responsive to a failure of the second LSP tunnel, selecting the Facility Bypass tunnel for one of the LSP tunnel and the second LSP tunnel, and
• (2) receiving a third PATH message for a third LSP tunnel with a third FAST_REROUTE object including a third DSTE Class Type therein for a different DSTE Class Type that the specified DSTE Class Type, and responsive to a failure of the third LSP tunnel, selecting a second Facility Bypass tunnel for the third LSP tunnel such that the second Facility Bypass tunnel supports the different specified DSTE Class Type.

A Label Edge Router (LER) network element comprising one or more ports and circuitry connected thereto for forwarding and control, wherein the circuitry is configured to:

• transmit a PATH message for a Label Switched Path (LSP) tunnel in a Multiprotocol Label Switching (MPLS) network with a specified DiffSery Traffic Engineering (DSTE) Class Type, wherein a FAST_REROUTE object is included in the PATH message which indicates Facility Bypass is desired, and wherein the DSTE Class Type is based on the PATH message, wherein the DSTE Class Type for the LSP tunnel is stored at a Point of Local Repair (PLR) to ensure a Facility Bypass tunnel used for the LSP tunnel supports the specified DSTE Class Type;
• one of
• (1) transmit a second PATH message for a second LSP tunnel with a second FAST_REROUTE object including a second DSTE Class Type that is the same as the specified DSTE Class Type, and responsive to a failure of the second LSP tunnel, the PLR is configured to select the Facility Bypass tunnel for one of the LSP tunnel and the second LSP tunnel, and
• (2) transmit a third PATH message for a third LSP tunnel with a third FAST_REROUTE object including a third DSTE Class Type therein for a different DSTE Class Type than the specified DSTE Class Type, and responsive to a failure of the third LSP tunnel, the PLR is configured to select a second Facility Bypass tunnel for the third LSP tunnel such that the second Facility Bypass tunnel supports the different specified DSTE Class Type.