A Robust Approach for the Detection and Prevention of Conflicts in I2NSF Security Policies

In order to maintain a sufficient protection level of their infrastructure, automating security management is at the core of current operators issues. The Interface to Network Security Function (I2NSF) is a framework that takes part of the Intent-Based Networking (IBN) paradigm. It consists of automating the translation of high-level policies into low-level configurations of Network Security Functions (NSF) and appears as a promising way to overcome the complexity of this challenging task. However, if the I2NSF framework provides a comprehensive architectural and data model for such an automation, it provides neither detection nor prevention mechanisms against conflicting security requirements. In this paper, we assess to what extent state-of-the-art mechanisms can shift the initial I2NSF proposal toward a robust framework. As such, we extend (1) the reference architecture to integrate some checking components and (2) the consumer-facing data model to enforce separation constraints and partial ordering relationships. By considering a large set of rules and conflicting situations, we evaluate the performance of our solution within an early implementation of I2NSF achieved in an IETF Hackathon.