Performance evaluation and tuning of Virtual Infrastructure Managers for (Micro) Virtual Network Functions

Virtualized Network Functions (VNFs) are emerging as the keystone of 5G network architectures: flexibility, agility, fast instantiation times, consolidation, Commercial Off The Shelf (COTS) hardware support and significant cost savings are fundamental for meeting the requirements of the new generation of mobile networks. In this paper we deal with the management of the virtual computing resources for the execution of Micro VNFs. This functionality is performed by the Virtual Infrastructure Manager (VIM) in the NFV MANagement and Orchestration (MANO) reference architecture.We discuss the VIM instantiation process and propose a generic reference model, starting from the analysis of two Open Source VIMs, namely OpenStack Nova and Nomad. We implemented a tuned version of the VIMs with the specific goal of reducing the duration of the instantiation process. We realized a performance comparison of the two VIMs, both considering the plain and the tuned versions. The tuned VIMs and the performance evaluation tools that we have employed are provided openly and can be downloaded from our repository.