Article

An Efficient Content Delivery System for 5G CRAN Employing Realistic Human Mobility

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Abstract

Today's modern communication technologies such as cloud radio access and software defined networks are key candidate technologies for enabling 5G networks as they incorporate intelligence for data-driven networks. Traditional content caching in the last mile access point has shown a reduction in the core network traffic. However, the radio access network still does not fully leverage such solution. Transmitting duplicate copies of contents to mobile users consumes valuable radio spectrum resources and unnecessary base station energy. To overcome these challenges, we propose huMan mObility-based cOntent Distribution (MOOD) system. MOOD exploits urban scale users' mobility to allocate radio resources spatially and temporally for content delivery. Our approach uses the broadcast nature of wireless communication to reduce the number of duplicated transmissions of contents in the radio access network for conserving radio resources and energy. Furthermore, a human activity model is presented and statistically analyzed for simulating people daily routines. The proposed approach is evaluated via simulations and compared with a generic broadcast strategy in an actual existing deployment of base stations as well as a smaller cells environment, which is a trending deployment strategy in future 5G networks. MOOD achieves 15.2% and 25.4% of performance improvement in the actual and small-cell deployment, respectively.

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... However, the conventional caching principle offers degradation in network traffic. This problem is solved in a unique study carried out by Lau et al. [23] that has used content distribution based on humans' mobility patterns-the study aimed for the spatial allocation of radio resources and targets for resource efficiency. The resource provision methods always challenge balancing the war between the under and overprovisioning to handle the trade-off between an uncertain pattern of the user demand and their level of experiences as feedback. ...
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... In short, the same data being shared independently with multiple users having the same requirements at the same time concludes in network congestion. Encountering such situations has brought the researchers' focus on the cause of network trafficking and its corresponding solution has been recommended through human mobility based content distribution [10]. This proposed algorithm is quite unpredictable as human mobility is highly uncertain and the accuracy of the algorithm is too low. ...
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Human mobility modeling at metropolitan scales
  • S Isaacman
  • R Becker
  • R Cáceres
  • M Martonosi
  • J Rowland
  • A Varshavsky
  • W Willinger
S. Isaacman, R. Becker, R. Cáceres, M. Martonosi, J. Rowland, A. Varshavsky, and W. Willinger, "Human mobility modeling at metropolitan scales," in Proceedings of the 10th international conference on Mobile systems, applications, and services (MobiSys). ACM, 2012, pp. 239-252.