Time and spectrum fragmentation-aware virtual optical network embedding in elastic optical networks

Abstract

Abstract Based on the concept of infrastructure as a service, optical network virtualization can improve the efficiency of network infrastructure by sharing the physical substrate network among different tenants and applications. The most important issue of optical network virtualization is how to handle the virtual optical network embedding (VONE) process, especially with the coexistence of the requests those can be reserved in advance (AR) and those require immediate reservation (IR). To address this issue, we investigate the time and spectrum fragmentation during the VONE process, which undermines the embedding success rate in elastic optical networks. A two-dimensional fragmentation measurement is first proposed to evaluate the resource state. Then we design a Two-Dimensional Fragmentation Aware (TDFA) VONE algorithm, and a Fragmentation and Continuity Aware (FCA) VONE algorithm, which decreases the two-dimensional fragmentation in the VONE process. Simulation results show that the proposed algorithms perform better than the baseline algorithm in blocking probability and spectrum utilization issues.