Impact on V2V VoIP Traffic between to ProSe-enabled End-points while Switching between Infrastructure Mode and Direct Mode

Abstract

Device-to-device (D2D) communication or Proximity Service (ProSe) is a proposed technique to increase the network capacity in a dense 5G network. This enables a base station (aka eNB) to perform in-band offloading of traffic between two ProSe enabled user equipments (UEs) so that the UEs can communicate directly over a side-link (SL) channel switching from conventional Infrastructure Mode (IM). However, such a mode-switching during an ongoing session may potentially degrade the Quality of Experience (QoE) for the end-consumer due to possible loss of packets in flight during the mode-switching instance. This paper presents, based on simulation of realistic conditions, a unique observation on how mode-switching affects a voice over IP (VoIP) session between two moving vehicles crossing each other from a distance. Observations reveal how a potential smart mode-switching decision, combining application context and instantaneous channel parameters, can improve performance both in terms of QoE as well as network capacity. To best of our understanding, this paper is a stepping stone towards a generic predictive model based scheduling policy to intelligently trigger mode-switch keeping the application context in consideration.