报告题目：Large-Scale Edge Cache Deployment Based on Spatio-Temporal WiFi Traffic Statistics
报 告 人：吕丰教授 中南大学计算机学院
报告摘要：How to deploy cache in large-scale WiFi system is not well studied yet quite challenging since numerous APs may have heterogeneous traffic characteristics, and future traffic conditions are unknown ahead. In this paper, given the cache storage budget, we explore the cache deployment in our campus WiFi system, which contains 8,000 APs and serves more than 40,000 active users, to maximize the long-term caching gain. Specifically, we first collect enormous user association records and conduct intensive spatio-temporal analysis on WiFi traffic consumption, gaining two major observations. First, per AP traffic consumption varies in a rather wide range and the proportion of AP distributes evenly within the range, indicating that the cache size should be heterogeneously allocated in accordance to the underlying traffic demands. Second, compared to a single AP, the traffic consumption of a group of APs (clustered by physical locations) is more stable, which means that the short-term traffic statistics can be used to infer the future long-term traffic conditions. We then propose our cache deployment strategy, named LEAD (i.e., Large-scale WiFi Edge cAche Deployment), in which we first cluster large-scale APs into well-sized edge nodes, then conduct the stationary testing on edge level traffic consumption and sample sufficient traffic statistics in order to precisely characterize long-term traffic conditions, and finally devise the TEG (Traffic-wEighted Greedy) algorithm to solve the long-term caching gain maximization problem. Extensive trace-driven simulations are carried out and simulation results demonstrate that LEAD is able to achieve the near-optimal caching performance and it outperforms other benchmark schemes significantly.
报告人概况：吕丰，2013年毕业于中南大学App学院，获工学学士学位；2018年毕业于上海交通大学计算机科学与工程系，获博士学位；2018.09-2019.12，在加拿大滑铁卢大学 (University of Waterloo) 电子与计算机工程系 (Department of Electrical and Computer Engineering) 从事博士后研究。2019年12月至今，任中南大学计算机学院特聘教授。发表相关学术论文30余篇，包括IEEE JSAC, IEEE IOTJ, IEEE TITS, IEEE TVT等国际著名期刊，以及 IEEE INFOCOM, IEEE ICDCS, IEEE SECON, IEEE ICC, IEEE GLOBECOM 等国际著名会议。