Research On Opportunistic Communication-based Mobile Data Offloading Protocol

Recently,a great variety of intelligent mobile devices have been emerging in the market.Considering that these wireless devices are in small volume and easy to carry,an increasing number of users prefer employing them to access the Internet.It already causes the explosive rise of mobile data traffic in the world wide.Therefore,the cellular network will be under huge pressure.The overload and congestion in cellular network are inevitable in the near future.Mobile data offloading is regarded as a promising way to tackle this issue.However,owing to the stationary access points,the traditional offloading methods like Wi-Fi and Femtocell are extremely limited.The large amount of mobile devices can be regarded as potential network.Utilizing the idea that devices are network,this paper presents a social activity and geographic location awareness offloading(SAGLA)to tackle the above problem,which is based on opportunistic communication.This paper firstly introduces and classifies the existing mobile data offloading technology,pointing out their benefits,drawbacks and applicable scenario.Secondly,this paper introduces the node movement models that are extensively employed in wireless network simulation,and displays the performance of these models.Then this paper analyzes the framework,design idea and technological process of proposed SAGLA in detail.SAGLA offloading protocol includes three key points:the selection of publisher,the offloading decision making and the data routing among publisher.SAGLA offloading protocol defines the user's social activity by encountering frequency and connection stability of users.The user with higher social activity can make greater contribution to mobile data offloading in unit time.Therefore SAGLA offloading protocol always selects users whose social activity is ranked in top K% as publishers.In order to minimizing the waiting time,SAGLA offloading protocol adopts the region-dividing idea.The offloading decision is made by judging that if the subscribe/publisher pairs are located in the same sub-region.The data routing algorithm among publishers is proposed,which combines the historical encountering information and the real-time location and vector.At last,this paper introduces the opportunistic network environment and simulates the proposed SAGLA offloading protocol.In terms of offloading efficiency and average waiting time,the proposed SAGLA offloading protocol outperforms the other algorithms.Simultaneously,this paper analyzes the performance under different factors.