On Dynamic Service Function Chain Reconfiguration in IoT Networks

Network function virtualization (NFV) technology continues to gain more attention as a paradigm shift, and telecommunication services can be flexibly deployed and managed. Any service can be represented by a service function chain (SFC) that is a set of virtual network functions (VNFs) to be executed based on the strict order. The NFV-enabled SFCs applied in the future Internet-of-Things (IoT) networks emerge a challenging problem, particularly more and more IoT devices are trying to access their telecommunication services whenever and wherever, SFCs are needed to be dynamically and adaptively reconfigured, thus adapting to the service requests' dynamics for lower resource consumption and higher revenue for Internet service providers (ISPs). In this article, we study the SFC dynamic reconfiguration problem (SFC-DRP) in the IoT networks, a discrete-time Markov decision process (DTMDP)-based IoT SFC-DRP is formulated by guaranteeing the QoS and resource constraints. We subsequently propose a novel deep Dyna-Q (DDQ) approach to solve this model. Our proposal has been evaluated with the obtained results demonstrating an average CPU root-mean-square error (RMSE) of 0.17, compared to 0.75 obtained while using the original approach. Moreover, our proposed SFC reconfiguration technique can approximate the performance of the integer linear programming (ILP) model within a polynomial time, and outperform the existing benchmarks in terms of the reconfiguration overhead and the resource utilization ratio from service provisioning, respectively.