Device-to-device (D2D) based packet caching technologies recently attract increasing attention, thanks to their great potentials to facilitate network traffic offloading. Despite the many popular issues arising in the D2D caching area, one of the new perspectives, namely the competition due to the packet request diversity originating from various D2D user equipment (UE) groups is not sufficiently investigated. In this work, we analyze several key aspects of the competition for packet allocation among diverse packet requests. Firstly, we study the impact from diverse group proportions on the system throughput and the packet allocation fairness. Particularly, the novel group separation index (GSI) is introduced, which helps to reflect the packet allocation fairness. We derive and analyze both the upper and lower bounds of GSI. Secondly, we investigate how the concentration levels of diverse packet requests may affect the system performance, such as the impact from the caching size limit on packet allocation. Thirdly, we derive the average energy consumption metric using the binomial point process based network model, which facilitates a comprehensive evaluation of the competition among UE groups. Finally, simulations validate our proposed analysis method, which may provide important design hints for improving existing D2D caching schemes.

中文翻译：

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D2D 通信的多种请求感知数据包缓存策略的竞争分析


基于设备到设备（D2D）的数据包缓存技术最近引起了越来越多的关注，因为它们在促进网络流量卸载方面具有巨大的潜力。尽管 D2D 缓存领域出现了许多流行问题，但新观点之一，即源自各种 D2D 用户设备 (UE) 组的数据包请求多样性引起的竞争尚未得到充分研究。在这项工作中，我们分析了不同数据包请求之间数据包分配竞争的几个关键方面。首先，我们研究不同组比例对系统吞吐量和数据包分配公平性的影响。特别是，引入了新颖的组分离索引（GSI），有助于反映数据包分配的公平性。我们推导并分析了 GSI 的上限和下限。其次，我们研究不同数据包请求的集中程度如何影响系统性能，例如缓存大小限制对数据包分配的影响。第三，我们使用基于二项式点过程的网络模型推导出平均能耗度量，这有助于对UE组之间的竞争进行综合评估。最后，仿真验证了我们提出的分析方法，这可能为改进现有的 D2D 缓存方案提供重要的设计提示。