A Survey of Medium Access Mechanisms for Providing Robust Audio Video Streaming in IEEE 802.11aa Standard

In this chapter we present a novel selective retransmission scheme, based on congestion control algorithm. Our method is efficient in narrowband networks for multimedia applications, which demand higher bandwidth. Multimedia applications are becoming increasingly popular in IP networks, while in mobile networks the limited bandwidth and the higher error rate arise in spite of its popularity. These are restraining factors for mobile clients using multimedia applications such as video streaming. In some conditions the retransmission of lost and corrupted packets should increase the quality of the multimedia service, but these retransmissions should be enabled only if the network is not in congested state. Otherwise the retransmitted packet will intensify the congestion and it will have negative effect on the audio/video quality. Our proposed mechanism selectively retransmits the corrupted packets based on the actual video bit rate and the TCP-Friendly Rate Control (TFRC), which is integrated to the preferred DCCP transport protocol.

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Layered Design of CORBA Audio/Video Streaming Service in a Distributed Java ORB Middleware Multimedia Platform

Sixth International Conference on Software Engineering, Artificial Intelligence, Networking and Parallel/Distributed Computing and First ACIS International Workshop on Self-Assembling Wireless Networks (SNPD/SAWN'05) ◽

10.1109/snpd-sawn.2005.47 ◽

2005 ◽

Author(s):

Kyu C. Cho ◽

Yeong-Tae Song

Keyword(s):

Video Streaming ◽

Streaming Service ◽

Layered Design ◽

Audio Video

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IEEE 802.11ah: A Long Range 802.11 WLAN at Sub 1 GHz

Journal of ICT Standardization ◽

10.13052/jicts2245-800x.125 ◽

2013 ◽

pp. 83-108

Author(s):

Weiping Sun ◽

Munhwan Choi ◽

Sunghyun Choi

Keyword(s):

Wireless Lan ◽

Large Scale ◽

Transmission Range ◽

Mac Layer ◽

Medium Access ◽

Frequency Spectra ◽

Ieee 802.11Ah ◽

Phy Layer ◽

5 Ghz ◽

Access Mechanisms

IEEE 802.11ah is an emerging Wireless LAN (WLAN) standard that defines a WLAN system operating at sub 1 GHz license-exempt bands. Thanks to the favorable propagation characteristics of the low frequency spectra, 802.11ah can provide much improved transmission range compared with the conventional 802.11 WLANs operating at 2.4 GHz and 5 GHz bands. 802.11ah can be used for various purposes including large scale sensor networks, extended range hotspot, and outdoor Wi-Fi for cellular traffic offloading, whereas the available bandwidth is relatively narrow. In this paper, we give a technical overview of 802.11ah Physical (PHY) layer and Medium Access Control (MAC) layer. For the 802.11ah PHY, which is designed based on the down-clocked operation of IEEE 802.11ac’s PHY layer, we describe its channelization and transmission modes. Besides, 802.11ah MAC layer has adopted some enhancements to fulfill the expected system requirements. These enhancements include the improvement of power saving features, support of large number of stations, efficient medium access mechanisms and throughput enhancements by greater compactness of various frame formats. Through the numerical analysis, we evaluate the transmission range for indoor and outdoor environments and the theoretical throughput with newly defined channel access mechanisms.

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Recursos tecnológicos audiovisuales de formación en red: sistemas streaming media y teleinmersivos

Education in the Knowledge Society (EKS) ◽

10.14201/eks.7078 ◽

2010 ◽

Vol 11 (2) ◽

pp. 214-231

Author(s):

Juan Antonio Juanes Méndez ◽

Mª Auxiliadora Velasco Marcos ◽

Francisco Javier Cabrero Fraile ◽

José Miguel Sánchez Llorente ◽

Ma José Rodríguez Conde

Keyword(s):

Video Streaming ◽

Streaming Media ◽

E Learning ◽

La Red ◽

Audio Video

Presentamos dos modalidades tecnológicas de enseñanza en red: la consolidada y ampliamente utilizada tecnología video-streaming, y el futuro de la comunicación a distancia, la teleinmersión.La primera permite la transmisión de audio/vídeo por la red para que puede ser vista por el usuario en su ordenador personal, desde cualquier lugar que disponga de una conexión a red. La información será recibida y decodificada por el usuario final utilizando cualquier reproductor de los que existen en el mercado.La teleinmersión, por su parte, permite crear espacios virtuales de colaboración entre profesionales, ofreciendo entornos muy cercanos a la realidad. Esta tecnología revolucionará, sin duda, nuestros sistemas de enseñanza en los próximos años, facilitando la interacción profesor-alumno. Es evidente que la formación e-learning aporta a los alumnos y a los docentes grandes ventajas como: menores tiempos de aprendizaje, flexibilidad de horarios y de ubicación geográfica, entre otras.

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Multimedia Compression Techniques for Streaming

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.l3383.1081219 ◽

2019 ◽

Vol 8 (12) ◽

pp. 3876-3881

Keyword(s):

Video Streaming ◽

Video Compression ◽

Streaming Data ◽

Network Bandwidth ◽

Extensive Analysis ◽

The World ◽

Multimedia Compression ◽

To Come ◽

Audio Video ◽

Viewing Experience

With the growing popularity of streaming content, streaming platforms have emerged that offer content in resolutions of 4k, 2k, HD etc. Some regions of the world face a terrible network reception. Delivering content and a pleasant viewing experience to the users of such locations becomes a challenge. audio/video streaming at available network speeds is just not feasible for people at those locations. The only way is to reduce the data footprint of the concerned audio/video without compromising the quality. For this purpose, there exists algorithms and techniques that attempt to realize the same. Fortunately, the field of compression is an active one when it comes to content delivering. With a lot of algorithms in the play, which one actually delivers content while putting less strain on the users' network bandwidth? This paper carries out an extensive analysis of present popular algorithms to come to the conclusion of the best algorithm for streaming data. Both audio and video compression are put under scrutiny and are compared on various aspects prime to delivery of data.

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