Description: The problem of minimizing the delay of media content during online broadcasting is considered. The object of the study is the media server platforms used to organize online broadcasts of media content. Objective of the research is to study the delay time for the delivery of media content in the process of online broadcasting. Method. The stages of video stream transmission are investigated. During the experiments, it was found that the greatest time spent on delivery is due to the processing of the video stream in the media server. The delay in the media server occurs due to signal transformations. The analysis of the most common media servers on the media services market that allow you to organize online broadcasting at the regional level is carried out. These are Ant Media Server 1.7.2, MistServer 2.14.1, Nimble Streamer Server 3.5.4, Red5 1.1.1, Wowza Streaming Engine 4.7. A technique is proposed for estimating the time delay for the delivery of media content in streaming networks. The developed methodology makes it possible to determine both the total delay time and its components at each of the stages of delivery. A generalized structure of the information and telecommunication system for modeling the process of streaming broadcasting is proposed. The model allows creating equal conditions for testing selected media server platforms. The features of this model are: ease of implementation, the ability to use standard components, open documentation, the ability to scale in heterogeneous networks. A feature of the technique is the combination of direct and indirect methods of measuring the delay time. Results. To obtain an average estimate of the delay time at each stage, a series of experiments was carried out using the RTMP and HLS protocols. The proposed methodology makes it possible to evaluate both the total delay time for the delivery of the video stream and the delay time at individual stages. The application of the methodology makes it possible to conduct a preliminary assessment of the existing infrastructure. This allows us to draw conclusions about the necessary modernization of the overall network architecture and its individual components. It was found that the fraction of the delay time in the media server is the most significant in percentage terms relative to the total delay. Conclusions. A methodology for estimating the delivery time of streaming video is proposed. Architecture has been developed and a system has been implemented to automate typical experiments to determine the time intervals for streaming video in distributed systems. The created tools allow making an informed choice of the optimal configuration of streaming video broadcasting systems of regional broadcasting companies.
Keywords: delay time, media server platform, online broadcast, video content, protocol
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