A distributed multicast label switched path setup scheme to solve the multi-destination reservation collision

Abstract

Generalized Multi-Protocol Label Switching (GMPLS) appears as a promising candidate to implement the control plane for next-generation optical networks. In GMPLS-based wavelength division multiplexing (WDM) optical networks, existing resource reservation protocol (RSVP) may fail to setup a multicast Label Switched Path (LSP) with high probability, since multiple destinations in one multicast session may reserve different wavelengths and result in reservation collision at branch nodes. In this work, we extend the existing GMPLS RSVP signaling protocol and propose an efficient scheme to set up optical multicast LSP and avoid wavelength resources collision, called Last-hop Label Set (LLS) scheme, by introducing a new object called Last-hop Label Set object in Resv message. Once the setup of a multicast LSP fails caused by wavelength reservation collision at a branch node, the branch node can re-reserves a new wavelength according to the Last-hop Label Set object within Resv messages. The numerical results indicate that the proposed LLS scheme offers lower blocking probability compared to the existing GMPLS signaling scheme.