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XMAS: An Efficient Mobile Adaptive Streaming Scheme Based on Traffic Shaping
Kim, Seohyang,Kim, Chongkwon IEEE 2019 IEEE transactions on multimedia Vol.21 No.2
<P>Adaptive video streaming can provide adequate Quality of Experience by dynamically adjusting video rates in responding to fluctuating service conditions. However, adaptive video streaming shows dismal performances in wireless networks where several players share a wireless bottleneck link. This paper proposes a novel video rate selection scheme called XMAS for efficient video streaming in wireless networks. XMAS consists of two components: an available bandwidth estimation part and a video rate selection part. To redress the problem of inaccurate bandwidth estimation due to peculiar <SMALL>on-off</SMALL> transmission patterns of mobile video streaming, we devised a novel client-based traffic shaping scheme that effectively throttles server's packet transmission. Equipped with accurate bandwidth estimates, XMAS determines target transmission rates considering playback buffer levels. We implemented XMAS on Linux and performed rigorous experiments to analyze its behavior and performance. Our performance results showed that XMAS achieves up to 20% increase in average video rates while reducing rebuffer rates significantly.</P>
eff-HAS: Achieve Higher Efficiency in Data and Energy Usage on Dynamic Adaptive Streaming
Kim, Seohyang,Oh, Hayoung,Kim, Chongkwon The Korean Institute of Communications and Informa 2018 Journal of communications and networks Vol.20 No.3
With the limited battery life of mobile devices and the full usage of shared network resources, mobile users are required to devise canny and amicable plans for energy and data consumption. In this paper, we propose an efficient chunk-scheduling strategy for adaptive video streaming which enhances per-power data utility. We first reveal that currently available chunk-scheduling strategies for adaptive video streaming do not consider the general viewing patterns of streaming users, causing a severe inefficiency in terms of not only data usage but also energy consumption. We then propose a energy- and data-efficient chunk scheduling algorithm that increases the per-power data utility for single bitrate encoded videos. We further extend the basic algorithm customizing it to dynamic adaptive streaming over HTTP (DASH) formatted video streaming systems, the most popular video streaming technique. We implemented the proposed scheme and the experiment results show that, while consuming 2% less energy, the scheme reduces the overall data wastage by 55% compared to a prior competing scheme.
Energy Cognitive Dynamic Adaptive Streaming over HTTP
( Seohyang Kim ),( Hayoung Oh ),( Chongkwon Kim ) 한국인터넷정보학회 2015 KSII Transactions on Internet and Information Syst Vol.9 No.6
CISCO VNI predicted an average annual growth rate of 66% for mobile video traffic between 2014 and 2019 and accordingly much academic research related to video streaming has been initiated. In video streaming, Adaptive Bitrate (ABR) is a streaming technique in which a source video is stored on a server at variable encoding rates and each streaming user requests the most appropriate video encoding rate considering their channel capacity. However, these days, ABR related studies are only focusing on real-time rate adaptation omitting energy efficiency though it is one of the most important requirement for mobile devices, which may cause dissatisfaction for streaming users. In this paper, we propose an energy efficient prefetching based dynamic adaptive streaming technique by considering the limited characteristics of the batteries used in mobile devices, in order to reduce the energy waste and provide a similar level of service in terms of the average video rate compared to the latest ABR streaming technique which does not consider the energy consumption. The simulation results is showing that our proposed scheme saves 65~68% of energy at the average global mobile download speed compared to the latest high performance ABR algorithm while providing similar rate adaptation performance.
기회주의적 네트워크에서 노드의 그룹 친밀성 정보를 이용한 메시지 전달 기법
김서향(Seohyang Kim),오하영(Hayoung Oh),김종권(Chongkwon Kim) 한국정보과학회 2015 정보과학회논문지 Vol.42 No.7
기회주의적 네트워크에서는 각 메시지들이 저장, 운반 및 전달을 반복하면서 목적지까지 전송된다. 최근 소셜 네트워크가 활성화되면서 기존의 많은 연구들은 메시지 전송 시 사회관계망을 고려하여, 기회적 메시지 전송에서의 성능 향상을 보여주었다. 하지만 기존 연구들은 사회관계망을 구성하고 있는 모든 노드들은 서로 무조건 협력한다는 강한 가정 아래 전송 범위 안에 메시지를 수신할 수 있는 노드가 발견되면 무조건 메시지를 전달했다. 또한, 단기적인 접촉 횟수 및 지역적 사회관계만 고려하고 최종 목적지와의 평균적인 관계는 고려하지 못했다. 본 논문에서는 기회주의적 네트워크에서 메시지 전달 시 노드의 그룹 친밀성 정보를 이용하여, 목적지 노드와 친밀도가 높은 노드를 통해 메시지를 전달함으로써 적은 메시지 복사수로 목적지 노드에 메시지를 전달하는 기법을 제안한다. 성능평가를 통해 제안 기법이 기존 기법에 비해 오버헤드 측면에서 최대 20%까지 성능향상이 있음을 보였다. In opportunistic networks, each message is delivered to the destination by repeating, storing, carrying, and forwarding the message. Recently, with the vitalization of social networks, a large number of existing articles have shown performance improvement when delivering the message and considering its social relational networks. However, these works only deliver messages when they find nodes, assuming that every node cooperates with each other unconditionally. Moreover, they only consider the number of short-term contacts and local social relations, but have not considered each node’s average relation with the destination node. In this paper, we propose novel message sending techniques for opportunistic networks using nodes’ social network characteristics. In this scheme, each message is delivered to the destination node with fewer copies by delivering it mostly through nodes that have high intimacy with the destination node. We are showing that our proposed scheme presents a 20% performance increase compared to existing schemes.