Segment-Based Robust Fast Optical Reservation Protocol

In a partial wavelength-convertible optical network with a fraction of its nodes capable of wavelength conversion, each lightpath transverses path segments with independent wavelength-continuity constraints. Taking advantage of the segment-based constraint independency, the two-phase Robust Fast Optical Reservation Protocol (S-RFORP) assigns end-to-end wavelengths along a selected route during on-demand lightpath setup by employing parallel segment-based wavelength discovery/reservation to minimize the overall wavelength assignment delay. Also employs recovery processing to minimize the wavelength assignment blocking. S-RFORP avoids costly path-based recovery processing that incurs end-to-end route re-selection delay, and avoids costly parallel link-based signaling overheads. In terms of wavelength assignment delay and blocking, simulation results under different traffic loadings show that S-RFROP outperforms other serialized link-based processing protocols in sparse, medium or high wavelength-convertible networks; and it outperforms other parallel link-based processing protocols in medium and high wavelength-convertible networks.