Summary of Mathematics doctoral thesis: Research on QoS assurance for multimedia data on wireless Adhoc network

Multimedia communications includes many efficient and highly efficient methods for exchanging information, an issue that is becoming increasingly necessary in the context of the rapid advancement of advanced network technologies such as broadband, wireless networks.
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Summary of Mathematics doctoral thesis: Research on QoS assurance for multimedia data on wireless Adhoc networkMINISTRY OF EDUCATION VIETNAM ACADEMY AND TRAINING OF SCIENCE AND TECHNOLOGYM GRADUATE UNIVERSITY SCIENCE AND TECHNOLOGY ------------------------------- NGO HAI ANH RESEARCH ON QOS ASSURANCE FOR MULTIMEDIA DATA ON WIRELESS AD HOC NETWORK Major: Mathematical Theory for Informatics Code: 62 46 01 10 SUMMARY OF MATHEMATICS DOCTORAL THESIS Ha Noi - 2020Công trình được hoàn thành tại: Học viện Khoa học và Công nghệ - Viện Hàn lâm Khoa học và Công nghệ Việt Nam Người hướng dẫn khoa học 1: PGS.TS. Phạm Thanh Giang Người hướng dẫn khoa học 2: PGS.TS. Nguyễn Văn Tam Phản biện 1: Phản biện 2: Phản biện 3:Luận án được bảo vệ trước Hội đồng chấm luận án tiến sĩ, họp tại Họcviện Khoa học và Công nghệ - Viện Hàn lâm Khoa học và Công nghệViệt Nam vào hồi giờ, ngày tháng năm 2020.Có thể tìm hiểu luận án tại:- Thư viện Học viện Khoa học và Công nghệ- Thư viện Quốc gia Việt Nam INTRODUCTION1. The necessity of the thesis Nowadays, wireless is becoming more and more popular. The ad-vantage of wireless networks is the portability and limitless freedom ofwired or fixed connections. It is very simple to have two or more com-puters connected together by radio for data transmission or resourcesharing. However, there are many complex technologies behind wire-less networks, in which Quality of Service (QoS) is an important areawith the goal of increasing network performance. In the components of the wireless network, the IEEE 802.11 stan-dard plays the most important role, it covers the principle of operationof both MAC and PHY sub-layers. However, the IEEE 802.11 stan-dard – the unofficial standard for ad hoc wireless networks does notwork well with some factors such as delay, throughput, and especiallythe fairness in ad hoc networks. An ad hoc wireless network is a mobile distributed network inwhich the stations in the network can move freely. Moving stations notonly causes delays in setting up a new network configuration, but alsochanges the communication conditions affecting network throughput. Multimedia communications includes many efficient and highlyefficient methods for exchanging information, an issue that is becom-ing increasingly necessary in the context of the rapid advancementof advanced network technologies such as broadband, wireless net-works,. . . Due to the limitations of technology, communication betweencomputers was originally intended for pure text data, but audio, staticand dynamic images, animation is suitable for human senses. Thus, 1the need for multimedia data communication is indispensable in to-day’s society. Communication can be based on traditional wired orwireless networks, in which wireless networks have many advantagessuch as mobility, portability, support for many different types of de-vices or terrains. However, wireless networks with mobile charac-teristics, depending on the factors of temperature, humidity, interfer-ence,. . . always have problems of Quality of Service (QoS), for multi-media data, this problem becomes more and more difficult. Voice applications have features that are vastly different from tra-ditional data transmission applications. This data itself is always real-time, transmitting of this data type must have minimal delay in packettransmission as well as not accept loss of packets, wrong-order trans-mission of packets. . . . Ensuring Quality of Service for multimedia data in wireless net-works is a meaningful topic and has been analyzed and studied bymany researches. Some recent studies suggest a number of methodssuch as analyzing at the link layer and MAC sub-layer to proposescheduling improvements to achieve an appropriate level of fairnessbetween data flows.2. Research motivation There are currently several solutions for quality of multimedia datain ad hoc networks. However, there are still some shortcomings thatneed further research and completion, as follows: With the always-shared and limited bandwidth of wireless links,the bandwidth competition moves from the router queue to channelaccess time, so the value Contention Window (CW) does not specify 2the baud rate of the wireless node. Therefore, research results that areavailable in wired networks can be directly applied to wireless net-works. For example, to extend the Kelly speed control algorithm onwireless networks, neighboring nodes must regularly exchange infor-mation. To avoid large message overhead, some studies have explored meth-ods that use the distributed contenti ...