论文标题
无线网络中的动态编码缓存
Dynamic Coded Caching in Wireless Networks
论文作者
论文摘要
我们考虑在宏基站(MBS)提供的区域中小型基站(SBS)的编码内容的分布和动态缓存。具体而言,内容是使用最大距离可分开代码编码的,并根据live(TTL)缓存驱逐策略进行缓存,该策略允许在定期时间从缓存中删除编码的数据包。移动用户请求特定内容从通信范围内的SBS下载编码数据包。如果需要其他数据包来解码文件,则将从MBS下载。我们制定了一个优化问题,该优化问题有效地通过数值解决,提供了将整个网络负载最小化的TTL缓存策略。我们证明,当请求到达爆发时,使用TTL缓存策略的分布式编码的缓存可以大大减少网络负载。我们展示了如何利用TTL缓存策略的分布式编码的缓存问题,可以分析为特定的单个缓存,即凸优化问题。我们的问题包括静态缓存和单个缓存作为特殊情况。我们证明,有趣的是,在泊松请求过程中,静态缓存是最佳的,而对于单个缓存,优化问题具有令人惊讶的简单解决方案。
We consider distributed and dynamic caching of coded content at small base stations (SBSs) in an area served by a macro base station (MBS). Specifically, content is encoded using a maximum distance separable code and cached according to a time-to-live (TTL) cache eviction policy, which allows coded packets to be removed from the caches at periodic times. Mobile users requesting a particular content download coded packets from SBSs within communication range. If additional packets are required to decode the file, these are downloaded from the MBS. We formulate an optimization problem that is efficiently solved numerically, providing TTL caching policies minimizing the overall network load. We demonstrate that distributed coded caching using TTL caching policies can offer significant reductions in terms of network load when request arrivals are bursty. We show how the distributed coded caching problem utilizing TTL caching policies can be analyzed as a specific single cache, convex optimization problem. Our problem encompasses static caching and the single cache as special cases. We prove that, interestingly, static caching is optimal under a Poisson request process, and that for a single cache the optimization problem has a surprisingly simple solution.