Towards Latency-aware vNF Placement on Heterogeneous Hosts at the Network Edge.

In this paper, we investigate the optimal placement of vNFs over the distributed edge network while considering the heterogeneity of packet processing elements. Unlike previous efforts in this domain, our proposed hybrid placement scheme places vNFs on user space hosts and the network data plane to efficiently minimise end-to-end path latency and achieve faster service delivery. We formulate and solve the Hybrid vNF Placement Problem as a linear integer programming (ILP) problem and propose a hybrid placement heuristic algorithm (HYPHA), which performs an incremental placement of vNFs on heterogeneous hosts to find a near-optimal solution to the problem quickly. We evaluated our proposed solution using a simulation of real-world network topology with realistic latency conditions. We show that leveraging the fast packet processing speed of the network data plane in conjunction with abundant user space resources for vNF placement yields minimal overall end-to-end latency and fulfils the placement of a diverse set of vNF requests to speed up service delivery. Also, our results show that HYPHA can obtain near-optimal vNF mapping while incurring fewer latency threshold violations set by network operators.