Dynamic service provisioning of hybrid advanced and immediate requests in SDM-EONs

Abstract

Hybrid immediate request (IR) and advanced reservation (AR) is an inevitable traffic model for future SDM-EONs to accommodate uncertainty and abundance of services. Different from the traditional IR handling instant services like chat messaging, AR can balance the traffic load by postponing allocation to delay-tolerant requests such as cloud computing, e-science, IPTV etc. Although IR/AR mixed traffics are essential in future SDM-EONs, several problems arise especially when solving dynamic RSCA problems. Most importantly, inter-core crosstalk (XT) and resource fairness need to be considered to satisfy high-quality transmission and to avoid unnecessary resource occupation of formerly arriving AR requests.We propose a dynamic HTA-RSCA algorithm that combines time recycling and reuse mechanisms in the time domain with routing, spectrum and core assignment (RSCA) in the spatial-spectrum domain. Specially, pretreatment techniques include super-channel (Sp-Ch) order pre-definition and time-spectrum partition. These appropriate operations are ready for efficient resource searching and requests assignment. Taking transmission quality into consideration, XT-avoid principle is involved in Sp-Ch order pre-definition and dynamic time domain mechanisms to realize the fair and flexible provisioning. XT-awareness is included in the final allocation step to rank available resources options. Simulation results confirm that the dynamic HTA-RSCA can reduce network blocking probability (BP) than comparison algorithms. To the best of our knowledge, this is the first attempt applying time mechanisms to address dynamic provisioning of hybrid IR and AR requests in SDM-EONs.