Decision-Tree Placement Algorithm for Containerized VoIP VNFs: A Network Management Approach

Prior work identified that the Decision-Tree (DT) algorithm allocates the best placement location for a containerized software-defined networking controller virtual network function (SDN-VNF). However, this identification and placement criteria was restricted to OpenFlow network architectures. To address this limitation, this study enhances the DT algorithm to identify the optimal containerized VNF placement location for a Voice over Internet Protocol (VoIP) VNF, thus expanding the applicability of the DT algorithm to incorporate UDP networks carrying Session Initiation Protocol (SIP) packets. To validate the enhancement, this study compares two approaches for implementing the DT algorithm: first, using Netperf, and second, using a northbound Python application. The results indicate the DT algorithm offers significantly smaller and near-constant lead time (time required to identify the best placement location) when it is coupled with a northbound Python application compared to the Netperf approach. Furthermore, the second approach using the northbound Python application removes any Linux Operating System (OS) dependency (required with Netperf), which further benefits its adoption in multi-faceted VoIP networks. The outcome of this research enhances the body of knowledge on implementing optimal containerized VNF placement algorithms.