A Formal Model for Multi-objective Optimisation of Network Function Virtualisation Placement

Ranging from web caches to firewalls, network functions play a critical role in modern networks. Network function virtualisation (NFV) has gained significant interests from both industry and academia, thus making the study of their placement an active research topic. Due to multiple criteria that must be considered by stake holders, e.g. the minimisation of the end-to-end latency and overall energy consumption, the NFV placement problem is in principle a multi-objective optimisation problem. This paper develops a formal model for the NFV placement problem based on queuing theory. By using the popular NSGA-II as the optimiser, the effectiveness of the proposed model is validated through a series of proof-of-concept experiments. In particular, some genetic operators have been developed to match the characteristics of the problem.