Proactive congestion-aware burst scheduling (PCABS) technique for contention issues in high-speed transport networks using optical burst switching (OBS)

Abstract Optical burst switching (OBS) is emerging as a promising approach for the next generation of the optical internet, achieving a balance between the coarse granularity of circuit switching and the finer granularity of packet switching. However, one of the major challenges OBS networks face is burst contention at core nodes, which can lead to a high burst drop probability (BDP) and a decline in quality of service (QoS). The traditional ways to resolve contention, like using fiber delay lines (FDLs) and wavelength conversion, often tend to be reactive, costly, and not very effective. This paper introduces a novel, proactive scheme for dealing with contention, known as Proactive Congestion-Aware Burst Scheduling (PCABS). In this approach, core routers keep checks on their local contention levels and regularly share this information with edge routers. The edge routers then use these data to adjust the timing of outgoing bursts, creating a buffer to help prevent potential contention issues. The PCABS algorithm and its analytical model have been presented a thorough performance assessment conducted using OMNeT++. Simulation results on the NSFNET topology demonstrate that PCABS greatly reduces the network-wide BDP and enhances throughput when compared to standard OBS (FDL). This clearly shows that PCABS is an efficient way to resolve contention in the ever-evolving landscape of OBS environments.