2020 IEEE International Symposium
on Information Theory
21-26 June 2020 • Los Angeles, California, USA
| Paper ID | N.4.1 | ||
| Paper Title | Fundamental Limits of Wireless Caching Under Mixed Cacheable and Uncacheable Traffic | ||
| Authors | Hamdi Joudeh, Eleftherios Lampiris, Technische Universität Berlin, Germany; Petros Elia, EURECOM, France; Giuseppe Caire, Technische Universität Berlin, Germany | ||
| Session | N.4: Coded Caching II | ||
| Presentation | Lecture | ||
| Track | Networking and Network Coding | ||
| Manuscript | Click here to download the manuscript | ||
| Virtual Presentation | Click here to watch in the Virtual Symposium | ||
| Abstract | We consider cache-aided wireless communication scenarios where each user requests both a file from an a-priori generated cacheable library (referred to as ‘content’), and an uncacheable ‘non-content’ message generated at the start of the communication session. This scenario is easily found in real-world wireless networks, where the two types of traffic coexist and share limited radio resources. We focus our investigation on single-transmitter wireless networks with cache-aided receivers, where the wireless channel is modelled by a degraded Gaussian broadcast channel (GBC). For this setting, we study the (normalized) delay-rate trade-off, which characterizes the content delivery time and non-content communication rates that can be achieved simultaneously. We propose a scheme based on the separation principle, which isolates the coded caching problem from the physical layer transmission problem, and prove its information-theoretic order optimality up to a multiplicative factor of 2.01. A key insight emerging from our scheme is that substantial amounts of non-content traffic can be communicated while maintaining the minimum content delivery time, achieved in the absence of non-content messages; compliments of ‘topological holes’ arising from asymmetries in wireless channel gains. | ||
Plan Ahead
2021 IEEE International Symposium on Information Theory
11-16 July 2021 | Melbourne, Victoria, Australia
