Experimental demonstration of a PCE for Wavelength-Routed Optical Burst-Switched (WR-OBS) networks

Despite what the name may suggest, Wavelength-Routed Optical Burst-Switched networks (WR-OBS) are in fact highly dynamic optical circuit-switched networks, where requests for lightpath establishment are triggered by the arrival of data at the edge routers. While a WR-OBS, like any other wavelength-routed network, can benefit from the Path Computation Element (PCE) technology for route calculations, its high dynamism requires the introduction of a number of upgrades and extensions on the PCE and on its associated protocol (PCEP). Thus, we have designed, implemented and experimentally validated a novel PCE architecture for fast circuit-switched networks, like WR-OBS. Therefore, we discuss the key challenges when implementing a PCE for such a highly dynamic network, as well as the PCEP extensions required. Since PCEP runs on top of the TCP protocol, we also analyze the impact of the combination of two TCP features -delayed acknowledgment and the Nagle algorithm- on the performance of the PCEP protocol. Furthermore, we describe the implementation of an emulated experimental setup to validate and evaluate the performance of the new PCE architecture, and demonstrate its feasibility.