Design and Implementation of an SDN-based Offloading Mechanism across Heterogeneous Networks

• Main Authors: Liao, Chang-Li, 廖常利
• Other Authors: Chen, Jyh-Cheng
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/cf3d5z

碩士 === 國立交通大學 === 網路工程研究所 === 103 === Because of the tremendous increase in mobile data traffic, network operators have paid more attentions on offloading traffic from cellular networks to other networks. Nowadays, due to high deployment cost, network operators tend to deploy low-cost Wi-Fi APs to offload mobile data traffic. In this thesis, we propose a mechanism based on Software-Defined Networking (SDN) to determine when and how to offload mobile data traffic. We take four scenarios into account. There is a corresponding policy for each scenario. The policies are: (1) offloading data from LTE to Wi-Fi, (2) offloading data from LTE to Wi-Fi Direct Relay, (3) offloading data from LTE to Wi-Fi Direct, and (4) offloading data among radio access network (Inter-Radio Access Technology connectivity, Inter-RAT connectivity). Furthermore, in order to achieve the goal of Inter-RAT connectivity, we add local gateways in 3GPP and non-3GPP access networks and design a new S2a+ interface between the two gateways. By collaborating with Industrial Technology Research Institute (ITRI), we have implemented the mechanism and proved its feasibility. The experimental results demonstrate that the proposed mechanism can not only mitigate LTE network loads, but also provide users a good Quality of Experience (QoE) in different scenarios.