Verifying the configuration of virtualized network functions in software defined networks

The deployment of modular virtual network functions (VNFs) in software defined infrastructures (SDI) enables cloud and network providers to deploy integrated network services across different resource domains. It leads to a large interleaving between network configuration through software defined network controllers and VNF deployment within this network. Most of the configuration management tools and network orchestrators used to deploy VNF lack of an abstraction to express Assume-Guarantee contracts between the VNF and the SDN configuration. Consequently, VNF deployment can be inconsistent with network configurations. To tackle this challenge, in this paper, we present an approach to check the consistency between the VNF description described from a set of structural models and flow-chart models and a proposed deployment on a real SDN infrastructure with its own configuration manager. We illustrate our approach on virtualized Evolved Packet Core function.