Assessing NFV Network Recovery Strategies after Random Failures and Targeted Attacks

This paper investigates the critical role of network survivability under random failures or targeted attacks in Network Function Virtualization (NFV) environments and assesses the survivability of NFV networks under different recovery strategies. Through a comprehensive application of the ClusPR framework, we simulated various failure events, which include both random and targeted failures. Our survivability assessment focuses on the temporal dimension and compares different repair sequences in network recovery and explores potential mitigation strategies. These strategies involve re-optimization of network function placement upon structural network changes and prioritization of node repairs according to different centrality measures. Our findings revealed that the resilience of the network was greatly dependent on its specific topology and that the efficacy of the recovery strategies varied accordingly. In some cases, the use of sub-optimal strategies appeared to decrease the network survivability, demonstrating the importance of the recovery strategy. The results provide valuable insights into improving the survivability of NFV networks in the face of failures and can have implications for network management and policy.