Point to multi-point label switched paths with label distribution protocol

A method comprising:

• receiving a first request for labels for a plurality of destination devices associated with a first point to multi-point (P2MP) label switched path (LSP);
• receiving first labels for the plurality of destination devices associated with the first P2MP LSP;
• receiving a second request for labels for a plurality of destination devices associated with a second P2MP LSP;
• determining whether a destination device associated with the first P2MP LSP is one of the plurality of destination devices associated with a second P2MP LSP;
• and
• when the destination device associated with the first P2MP LSP is one of the plurality of destination devices associated with a second P2MP LSP:
• sharing, between the first P2MP LSP and second P2MP LSP, one of the first labels for the plurality of destination devices associated with the first P2MP LSP;
• and
• sending a request for labels for an additional one or more destination devices associated with the second P2MP LSP.

A system comprising:

• a first source device;
• a second source device;
• an intermediate device;
• a plurality of destination devices associated with a first point to multi-point (P2MP) label switched path (LSP), wherein the first P2MP LSP connects the first source device to the intermediate device and the one or more destination devices associated with the first P2MP LSP;
• and
• a plurality of destination devices associated with a second point to multi-point (P2MP) label switched path (LSP), wherein the second P2MP LSP connects the second source device to the intermediate device and the one or more destination devices associated with the second P2MP LSP,
• wherein the intermediate device shares a same label for a first destination device associated with both the first and second P2MP LSPs, and requests an additional label for a second destination device associated with the first P2MP LSP.

A computer-readable storage medium comprising instructions stored thereon for causing a programmable processor to:

• generate a label distribution protocol message that includes both a label associated with a point to multi-point (P2MP) label switched path (LSP) and a forwarding equivalence class (FEC) element that identifies the P2MP LSP;
• and
• communicate the message in accordance with the label distribution protocol to a routing device receive a withdraw message from a downstream routing device on a downstream branch of the P2MP LSP,
• determine whether an additional downstream branch of the P2MP LSP exists;
• and
• propagate the withdraw message to an upstream routing device in the P2MP LSP when no additional downstream branch of the P2MP LSP exists.