Modeling and Evaluation of Elastic SFC Based on HCPN

Service Function Chaining (SFC) has enhanced the flexibility of Network Function Virtualization (NFV) through dynamic orchestration and reduced operational and maintenance costs, but challenges remain to achieve optimal elasticity. This study investigates the elasticity of SFC and addresses the current lack of an effective elasticity evaluation method. We propose a hierarchical Colored Petri Net (HCPN) model with temporal extensions to represent the ESFC behavior. It accurately simulates request processing, resource allocation, and elasticity policy execution. Then, we design a quantitative evaluation model based on multidimensional metrics and develop an evaluation algorithm to select the optimal ESFC from a candidate pool. The evaluations show that the proposed model and the elastic strategies are effective.