Mobile Short Video:Measurement,Analysis And Edge Caching

In recent years,with the rise of mobile Internet,short video platform is in the pro-cess of rapid development.Meanwhile,video applications also bring huge traffic pres-sure to the core network of mobile operators.Domestic 5G base stations and WLAN in public places are also in continuous expansion.Mobile edge caching technology can be used to cache short videos to edge nodes such as base stations or wireless access points,so as to reduce traffic transmission and relieve link pressure.Meanwhile,compared with the traditional VoD platform,users of the short video platform upload,comment and other behaviors have their own characteristics.Compared with long videos such as movies,variety shows and TV dramas,short videos have the characteristics of rapid popularity changes,spatial-temporal locality and short life cycle,which makes it diffi-cult for traditional caching algorithms to react quickly.This thesis first takes Douyin as an example to collect data from it,and introduces the collected data set in detail.Then,according to the collected data,the behaviors such as uploading and commenting among users on Douyin platform are analyzed.Through the analysis,it can be found that users have a high preference for short videos with a relatively new release time,and this preference decreases rapidly with the passage of time and users have an obvious preference for short videos with a relatively short distance.It has a certain spatio-temporal locality.And compared to the topic,users’preference for music is more concentrated.Based on the analysis results,this thesis proposes two cache replacement strategies for different scenarios.Firstly,in the base station scenario within the region,it considers the cooperation between operators and content service providers to design the caching strategy by using the measured spatio-temporal characteristics and collaborative caching,so as to reduce the traffic pressure of mobile operators.Simulation results show that this strategy is superior to the com-parison strategy in terms of traffic unloading rate and cache hit rate.Then,aiming at the problem that edge nodes are not sensitive to the change of short video content cache value,a strategy of edge cache replacement is proposed to estimate the video cache value by edge nodes themselves according to users’ interest in the theme and music of short video in the WLAN scenario.The experimental results show that the cache hit rate is better than the comparison cache strategy.