On establishing and task scheduling of data-oriented vNF-SCs in an optical DCI

The development of network function virtualization (NFV) enables service providers to provision various network services with virtual network function service chains (vNF-SCs). However, most of the existing studies on the service provisioning of vNF-SCs address only the flow-oriented ones, while the provisioning schemes of data-oriented vNF-SCs, each of which needs to process and transfer bulk data through a series of vNFs before a preset deadline, have not been fully explored yet. Therefore, this paper studies how to jointly optimize the establishing and task scheduling of data-oriented vNF-SCs in an optical datacenter interconnection (DCI), such that the probability of scheduling data-oriented vNF-SCs to satisfy their deadlines can be maximized. To make the best use of the resources in the optical DCI for meeting each vNF-SC’s deadline, we leverage dynamic programming (DP) to propose two time-efficient algorithms with deadline-prioritized and conflict-aware approaches. Extensive simulations evaluate the performance of our proposed algorithms in different network scenarios, and confirm their effectiveness. Specifically, compared with a greedy-based benchmark, our DP-based algorithms can reduce the blocking probability of data-oriented vNF-SCs by up to two magnitudes and maintain similar service completion time.