Wireless Device-to-Device Caching Networks: Basic Principles and System Performance

摘要: As wireless video transmission is the fastest-growing form of data traffic, methods for spectrally efficient on-demand streaming are essential to service providers and users alike. A key property asynchronous content reuse, such that a few dominant videos account large part but viewed by at different times. Caching on devices in conjunction with D2D communications allows exploit this property, provide network throughput significantly excess both conventional approach unicasting from base station traditional networks regular traffic. This paper presents semi-tutorial concise some recent results scaling laws caching contrasting competing based combinatorial cache design coded (BS) only, referred as multicasting. Interestingly, spatial reuse gain former multicasting latter yield, somehow surprisingly, same near-optimal behavior relevant regime where number files library smaller than users. Based our theoretical results, we propose holistic system incorporates microwave (2 GHz) well millimeter-wave links; direct connections can be used those rare requests cannot found local caches. We extensive simulations under variety settings, compare scheme other existing schemes BS. show that, despite similar laws, proposed offers very significant gains respect BS-only schemes.