714 research outputs found
User preference aware caching deployment for device-to-device caching networks
Content caching in the device-to-device (D2D) cellular networks can be utilized to improve the content delivery efficiency and reduce traffic load of cellular networks. In such cache-enabled D2D cellular networks, how to cache the diversity contents in the multiple cache-enabled mobile terminals, namely, the caching deployment, has a substantial impact on the network performance. In this paper, a user preference aware caching deployment algorithm is proposed for D2D caching networks. First, the definition of the user interest similarity is given based on the user preference. Then, a content cache utility of a mobile terminal is defined by taking the transmission coverage region of this mobile terminal and the user interest similarity of its adjacent mobile terminals into consideration. A general cache utility maximization problem with joint caching deployment and cache space allocation is formulated, where the special logarithmic utility function is integrated. In doing so, the caching deployment and the cache space allocation can be decoupled by equal cache space allocation. Subsequently, we relax the logarithmic utility maximization problem, and obtain a low complexity near-optimal solution via a dual decomposition method. Compared with the existing caching placement methods, the proposed algorithm can achieve significant improvement on cache hit ratio, content access delay, and traffic offloading gain
Quality of experience-centric management of adaptive video streaming services : status and challenges
Video streaming applications currently dominate Internet traffic. Particularly, HTTP Adaptive Streaming ( HAS) has emerged as the dominant standard for streaming videos over the best-effort Internet, thanks to its capability of matching the video quality to the available network resources. In HAS, the video client is equipped with a heuristic that dynamically decides the most suitable quality to stream the content, based on information such as the perceived network bandwidth or the video player buffer status. The goal of this heuristic is to optimize the quality as perceived by the user, the so-called Quality of Experience (QoE). Despite the many advantages brought by the adaptive streaming principle, optimizing users' QoE is far from trivial. Current heuristics are still suboptimal when sudden bandwidth drops occur, especially in wireless environments, thus leading to freezes in the video playout, the main factor influencing users' QoE. This issue is aggravated in case of live events, where the player buffer has to be kept as small as possible in order to reduce the playout delay between the user and the live signal. In light of the above, in recent years, several works have been proposed with the aim of extending the classical purely client-based structure of adaptive video streaming, in order to fully optimize users' QoE. In this article, a survey is presented of research works on this topic together with a classification based on where the optimization takes place. This classification goes beyond client-based heuristics to investigate the usage of server-and network-assisted architectures and of new application and transport layer protocols. In addition, we outline the major challenges currently arising in the field of multimedia delivery, which are going to be of extreme relevance in future years
Startup Delay Aware Short Video Ordering: Problem, Model, and A Reinforcement Learning based Algorithm
Short video applications have attracted billions of users on the Internet and
can satisfy diverse users' fragmented spare time with content-rich and
duration-short videos. To achieve fast playback at user side, existing short
video systems typically enforce burst transmission of initial segment of each
video when being requested for improved quality of user experiences. However,
such a way of burst transmissions can cause unexpected large startup delays at
user side. This is because users may frequently switch videos when sequentially
watching a list of short videos recommended by the server side, which can cause
excessive burst transmissions of initial segments of different short videos and
thus quickly deplete the network transmission capacity. In this paper, we adopt
token bucket to characterize the video transmission path between video server
and each user, and accordingly study how to effectively reduce the startup
delay of short videos by effectively arranging the viewing order of a video
list at the server side. We formulate the optimal video ordering problem for
minimizing the maximum video startup delay as a combinatorial optimization
problem and prove its NP-hardness. We accordingly propose a Partially Shared
Actor Critic reinforcement learning algorithm (PSAC) to learn optimized video
ordering strategy. Numerical results based on a real dataset provided by a
large-scale short video service provider demonstrate that the proposed PSAC
algorithm can significantly reduce the video startup delay compared to baseline
algorithms
Video Caching, Analytics and Delivery at the Wireless Edge: A Survey and Future Directions
Future wireless networks will provide high bandwidth, low-latency, and ultra-reliable Internet connectivity to meet the requirements of different applications, ranging from mobile broadband to the Internet of Things. To this aim, mobile edge caching, computing, and communication (edge-C3) have emerged to bring network resources (i.e., bandwidth, storage, and computing) closer to end users. Edge-C3 allows improving the network resource utilization as well as the quality of experience (QoE) of end users. Recently, several video-oriented mobile applications (e.g., live content sharing, gaming, and augmented reality) have leveraged edge-C3 in diverse scenarios involving video streaming in both the downlink and the uplink. Hence, a large number of recent works have studied the implications of video analysis and streaming through edge-C3. This article presents an in-depth survey on video edge-C3 challenges and state-of-the-art solutions in next-generation wireless and mobile networks. Specifically, it includes: a tutorial on video streaming in mobile networks (e.g., video encoding and adaptive bitrate streaming); an overview of mobile network architectures, enabling technologies, and applications for video edge-C3; video edge computing and analytics in uplink scenarios (e.g., architectures, analytics, and applications); and video edge caching, computing and communication methods in downlink scenarios (e.g., collaborative, popularity-based, and context-aware). A new taxonomy for video edge-C3 is proposed and the major contributions of recent studies are first highlighted and then systematically compared. Finally, several open problems and key challenges for future research are outlined
Survey of Transportation of Adaptive Multimedia Streaming service in Internet
[DE] World Wide Web is the greatest boon towards the technological advancement of modern era. Using the benefits of Internet globally, anywhere and anytime, users can avail the benefits of accessing live and on demand video services. The streaming media systems such as YouTube, Netflix, and Apple Music are reining the multimedia world with frequent popularity among users. A key concern of quality perceived for video streaming applications over Internet is the Quality of Experience (QoE) that users go through. Due to changing network conditions, bit rate and initial delay and the multimedia file freezes or provide poor video quality to the end users, researchers across industry and academia are explored HTTP Adaptive Streaming (HAS), which split the video content into multiple segments and offer the clients at varying qualities. The video player at the client side plays a vital role in buffer management and choosing the appropriate bit rate for each such segment of video to be transmitted. A higher bit rate transmitted video pauses in between whereas, a lower bit rate video lacks in quality, requiring a tradeoff between them. The need of the hour was to adaptively varying the bit rate and video quality to match the transmission media conditions. Further, The main aim of this paper is to give an overview on the state of the art HAS techniques across multimedia and networking domains. A detailed survey was conducted to analyze challenges and solutions in adaptive streaming algorithms, QoE, network protocols, buffering and etc. It also focuses on various challenges on QoE influence factors in a fluctuating network condition, which are often ignored in present HAS methodologies. Furthermore, this survey will enable network and multimedia researchers a fair amount of understanding about the latest happenings of adaptive streaming and the necessary improvements that can be incorporated in future developments.Abdullah, MTA.; Lloret, J.; Canovas Solbes, A.; García-García, L. (2017). Survey of Transportation of Adaptive Multimedia Streaming service in Internet. Network Protocols and Algorithms. 9(1-2):85-125. doi:10.5296/npa.v9i1-2.12412S8512591-
Digital Twin Based User-Centric Resource Management for Multicast Short Video Streaming
Multicast short video streaming (MSVS) can effectively reduce network traffic
load by delivering identical video sequences to multiple users simultaneously.
The existing MSVS schemes mainly rely on the aggregated video requests to
reserve bandwidth and computing resources, which cannot satisfy users' diverse
and dynamic service requirements, particularly when users' swipe behaviors
exhibit spatiotemporal fluctuation. In this paper, we propose a user-centric
resource management scheme based on the digital twin (DT) technique, which aims
to enhance user satisfaction as well as reduce resource consumption. Firstly,
we design a user DT (UDT)-assisted resource reservation framework.
Specifically, UDTs are constructed for individual users, which store users'
historical data for updating multicast groups and abstracting useful
information. The swipe probability distributions and recommended video lists
are abstracted from UDTs to predict bandwidth and computing resource demands.
Parameterized sigmoid functions are leveraged to characterize multicast groups'
user satisfaction. Secondly, we formulate a joint non-convex bandwidth and
computing resource reservation problem which is transformed into a convex
piecewise problem by utilizing a tangent function to approximately substitute
the concave part. A low-complexity scheduling algorithm is then developed to
find the optimal resource reservation decisions. Simulation results based on
the real-world dataset demonstrate that the proposed scheme outperforms
benchmark schemes in terms of user satisfaction and resource consumption.Comment: 13 pages, 11 figure
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