Transmission of MPEG-DASH over LTE

Abstract

A fast-paced rise in data transmission over mobile networks pushed network providers to upgrade their infrastructures from 3G to LTE towards 4G. LTE’s is better than previous mobile network versions in terms of data rate, low latency and flexible bandwidth supported by optimized packets. As traffic keeps growing, data transmission becomes slower. An individual streaming a full high definition video using mobile data would ideally have more than enough bandwidth (BW) in order to view it. However, normally this isn’t the case, and with multiple users using mobile data, BW becomes more limited. One solution to this is to adopt an adaptive bit rate technique, so if one where to encounter such a situation, the user can sacrifice some quality for the ability to stream the video. MPEG-DASH (MPEG-Dynamic Adaptive Streaming over HTTP) is a standard that allows the video stream to adapt according to channel conditions and is used by several media services providers. The 4G LTE Bandwidth is uninterruptedly occupied by a number of users, hence, conducting tests with uncontrolled traffic would give inaccurate results. Consequently, a private LTE testbed supplied by Vodafone is exploited to run controlled tests with respect to Radio channel characteristics and Traffic. This controlled environment gives the opportunity to emulate real life scenarios to be analysed and discussed. Using this standard, a laptop acting as a home server hosts videos based on the HTTP protocol that are streamed and analysed upon reception on another laptop at University’s Communications laboratory. Performance curves are plotted to provide a visual assessment of the optimal parameters and limitations of the LTE system under test.