Optimal Provisioning of Hybrid Service Function Chains with Guaranteed Disaster Resilience
Mohamed Abderrahmane Madani, Fen Zhou, Ahmed Meddahi · 2025
Network Function Virtualization (NFV) provides a flexible mechanism for deploying Virtual Network Functions (VNFs) within Service Function Chains (SFCs), thereby streamlining data transfers between end-users and edge/cloud resources. The distinct requirements for forward and backward traffic—each carrying different types of content—give rise to Hybrid SFCs (HSFCs), which must be carefully designed to address unique deployment and performance concerns. However, achieving robust disaster resilience in HSFC-based NFV environments poses significant challenges, as natural or hardware-induced disruptions within Disaster Zones (DZs) can degrade service quality or even cause outages. This paper describes the Resilient Hybrid Service Function Chain Resource Optimization (R-HSFC-RO) approach to ensure both efficient resource utilization and sustained service delivery under disaster conditions. Our model considers bandwidth consumption, computational resource allocation for VNF execution, VNF instantiation overheads, and end-to-end latency requirements. For resolution, we propose a Mixed-Integer Linear Programming (MILP) model and Constraint Programming (CP), thereby enabling optimal solutions. Simulation results demonstrate that R-HSFC-RO reduces total costs by up to 50%, enhances disaster resilience, and maintains high operational efficiency.