Synchronization of delay for OTT services in LTE

With the advent of networks of the fourth generation of LTE, the question arises of the transmission of voice sessions in these same networks. The most popular among mobile operators is the mechanism CS Fallback, which transfers the user terminal in a second or third generation voice communication network, and the IMS platform, which is a superstructure over the operator's network and provides Voice over LTE with high quality of services. But the alternative for the end user is Over-the-top (OTT) communication solutions, such as WhatsUp, Viber, Skype, FaceTime, etc. have driven user adoption of more advanced service behavior based on LTE. However, without Quality of Service (QoS) and Quality of Experience (QoE) measures fully satisfactory user experience cannot be provided. In this paper we present a new approach to study QoS of multimedia OTT services, based on the experiment was, where a call was made using the OTT Skype application from a mobile terminal to a PC. The mobile terminal itself was registered in the LTE network of the telecommunications operator. In the course of the experiment, three important quality indicators were measured for the evaluation of a particular service: jitter, delay, and packet loss. The input of the study revealed that the delay for the OTT service would change according to the bimodal distribution law. To determine the type of distribution, the entropy method was used, where the form of the distribution law was determined on the basis of values of the coefficient of entropy and counterexcess important for the given method. We also discuss how all these variables can be taken into account to predict the QoE of the service being studied. According to the received data, it can be argued that the delay values using OTT services are many values that ITU offers in Recommendation G. 114.