Supporting video streaming services and providing high Quality of Experience (QoE) to end users have become main concerns for cellular network operators. In this work, we present an architecture for improving the QoE of video streaming in cellular networks with high user density. The architecture employs progressive caching of video contents, Dynamic Adaptive Streaming over HTTP (DASH), and Device-to-Device (D2D) communication. The Base-Station (BS) controls the progressive caching process of video contents and the Peer-to-Peer (P2P) transmission of video segments among User Equipments (UEs). We present two different implementations of the architecture. The implementations differ in the employed approach for video contents caching and distribution over the UEs. We use the Discrete EVent System Specification (DEVS) formalism to build a model for the proposed architecture in an LTE-A network and use the model to study the performance achieved by the proposed architecture in terms of many video streaming QoE metrics.As video streaming is becoming the most popular application over cellular networks, providing reliable video streaming service is a key to differentiated competitiveness. As such, it is important to evaluate the quality of the video streaming service as perceived by the end user. Hence, quality measure has shifted from Quality of Service (QoS) to QoE. There are many factors that are used to measure video streaming QoE. The number of video rebufferings is an important factor. Increasing the number of rebufferings significantly reduces video streaming QoE, and hence, it should be avoided as much as possible. Initial delay is another factor that also reduces video streaming QoE. Video bit rate is a measurement of the amount of data in one second of the video. As the video bit rate increases, the video quality increases, which increases the QoE.
Related workD2D communication allows two UEs that are within proximity of each other to communicate without routing the traffic through the BS and the network infrastructure. This direct communication between UEs can be utilized to improve the capacity of cellular networks and improve the achieved data rates. D2D communication can also be utilized to extend the cell coverage and improve the service for users at the celledge. As such, D2D communication is one of the main technologies in the Fifth Generation (5G) cellular networks (Agiwal, Roy, and Saxena 2016). Much research has been conducted in recent years on D2D communication and developing applications for it in cellular networks (Asadi, Wang, and Mancuso 2014).