On the Game-Theoretic Analysis of Dynamic VNF Service Chaining in Edge-Cloud EONs

Network function virtualization (NFV) enables flexible, cost-effective, and timely deployment of new network services in elastic optical networks (EONs). Nowadays, the integration of cloud and edge computing becomes a prevailing trend, which has promoted the idea of edge-cloud EON (EC-EON) (i.e., a multi-domain EON that consists of a cloud domain and one or more edge domains). In this work, we study the dynamic provisioning of virtual network function based service chain (VNF-SC) requests in EC-EONs, and leverage game theory to explain why and how the cloud and edge domain managers (DMs) should collaborate when protecting their own interests. We first formulate the non-cooperative interactions between cloud and edge DMs as a two-stage Stackelberg game, prove the existence of Nash Equilibrium in the game, and propose an algorithm based on backward induction for the non-cooperative service provisioning. Next, we address the cooperative provisioning scheme where the DMs can reach an agreement for mutual benefit, and model it with Nash bargaining. Finally, we conduct extensive simulations to compare the non-cooperative and cooperative provisioning schemes with the traditional centralized approach in EC-EONs in-depth. Simulation results confirm the effectiveness of our non-cooperative and cooperative provisioning schemes on protecting the interests of DMs, and suggest that the cooperative provisioning scheme can outperform the traditional centralized approach in terms of blocking probability, when inter- and intra-domain VNF-SC requests both exist in an EC-EON.