Take-Away TV: Recharging Work Commutes With Predictive Preloading of Catch-Up TV Content

IEEE Trans. Wireless Commun.

et al. 2019

Self Cite

Caching of video files on user devices, combined with file exchange through device-to-device (D2D) communications is a promising method for increasing the throughput of wireless networks. Previous theoretical investigations showed that throughput can be increased by orders of magnitude, but assumed a Zipf distribution for modeling the popularity distribution, which was based on observations in wired networks. Thus the question whether cache-aided D2D video distribution can provide in practice the benefits promised by existing theoretical literature remains open. To answer this question, we provide new results specifically for popularity distributions of video requests of mobile users. Based on an extensive real-world dataset, we adopt a generalized distribution, known as Mandelbrot-Zipf (MZipf) distribution. We first show that this popularity distribution can fit the practical data well. Using this distribution, we analyze the throughput-outage tradeoff of the cache-aided D2D network and show that the scaling law is identical to the case of Zipf popularity distribution when the MZipf distribution is sufficiently skewed, implying that the benefits previously promised in the literature could indeed be realized in practice. To support the theory, practical evaluations using numerical experiments are provided, and show that the cache-aided D2D can outperform the conventional unicasting from base stations.

Section: Measured Data and Popularity Distribution Modelingmentioning

confidence: 99%

“…By observing Theorem 2, it is then obvious that we are not interested in cases that gc(M ) = o(M α ) and gc(M ) = ω(M ) since the former one gives an even worse outage, i.e., Po → 1, and the latter one gives worse throughput when Po → 0 12. Recall that S does not grow to infinity 13.…”

mentioning

confidence: 99%

Throughput–Outage Analysis and Evaluation of Cache-Aided D2D Networks With Measured Popularity Distributions

IEEE Trans. Wireless Commun.

et al. 2019

Self Cite

“…This paper uses an extensive set of real-world data, namely the dataset of the BBC iPlayer [14], [18], to obtain realistic video demand distributions. The BBC iPlayer is a video streaming service provided by BBC (British Broadcasting Corporation) that provides video content for a number of BBC channels without charge.…”

Section: The Measured Data and Modeling Resultsmentioning

confidence: 99%

Section: The Measured Data and Modeling Resultsmentioning

confidence: 99%

Performance of Caching-Based D2D Video Distribution with Measured Popularity Distributions

2019 IEEE Global Communications Conference (GLOBECOM)

et al. 2019

Self Cite

On-demand video accounts for the majority of wireless data traffic. Video distribution schemes based on caching combined with device-to-device (D2D) communications promise order-of-magnitude greater spectral efficiency for video delivery, but hinge on the principle of "concentrated demand distributions." This paper presents, for the first time, the analysis and evaluations of the throughput-outage tradeoff of such schemes based on measured cellular demand distributions. In particular, we use a dataset with more than 100 million requests from the BBC iPlayer, a popular video streaming service in the U.K., as the foundation of the analysis and evaluations. We present an achievable scaling law based on the practical popularity distribution, and show that such scaling law is identical to those reported in the literature. We find that also for the numerical evaluations based on a realistic setup, order-of-magnitude improvements can be achieved. Our results indicate that the benefits promised by the caching-based D2D in the literature could be retained for cellular networks in practice.

“…We remark that (26) and (27) are simply reformulations of (6), in which we isolate the terms containing variables to be optimized. Observing (26) and (27), it is then clear that (25) is a linear program. Note that we consider only equality constraints in (25b) because of Proposition 1.…”

Section: A Proposed Coordinated Caching Policy Designmentioning

confidence: 99%

Individual Preference Aware Caching Policy Design for Energy-Efficient Wireless D2D Communications

GLOBECOM 2017 - 2017 IEEE Global Communications Conference

2017

Cache-aided wireless device-to-device (D2D) networks allow significant throughput increase, depending on the concentration of the popularity distribution of files. While many previous investigations assumed that all users have the same preference, this may not be true in practice. This work investigates whether and how the information about individual preferences can benefit such cache-aided D2D networks. Considering a clustered network, we derive a network utility that considers both the user distribution and channel fading effects, and formulate a utility optimization problem. This formulation can be used to optimize several important quantities, including throughput, energy efficiency (EE), and hit-rate, and solve different tradeoff problems. We provide designs of caching policies that solve the utility maximization problem with and without coordination between the devices, and prove that the coordinated design can obtain the stationary point under a mild assumption. Using simulations of practical setups, we show that by properly exploiting the diversity entailed by the individual preferences, performance can be improved significantly. Besides, different types of tradeoffs exist between different performance metrics, and they can be managed by means of proper caching policy and cooperation distance design.