Smart Caching for Supporting Video Streaming in Heterogeneous Wireless Networks

Broadband wireless networks will be a key feature of future communication technology. Mobilizing the services and applications used from desktop PCs is the next logical step in enhancing the Internet. But especially video streaming services burden wireless networks with resource consuming tasks. Due to this reason the realization of high quality streams is hard to achieve through wireless LANs. Especially in dense populated urban areas WLAN systems suffer from shadowing and propagation effects which limit the coverage range and performance. A complete illumination in such environments with broadband access is not achievable. Moreover areas of good coverage will interchange with regions of only rudimentary or even no wireless access. This heterogeneity in network performance causes a lot of problems for streaming services. Usually they require a fixed certain level in bit rate. Although streaming protocols in the future will be adaptable to varying bandwidth the quality reduction if often not acceptable. Buffering techniques which are already employed on today’s protocols may partly solve the problem but only more sophisticated approaches, namely Smart Caching, will fully succeed. Smart Caching is a technique to overcome the problems caused by the diverseness of available radio bandwidth. Its purpose is to maximize resource utilization in regions of broadband access and to live on buffered data in periods of low network performance or broken connections. For video streaming services this implies that a sufficient amount of data is stored in the user terminal to bridge even longer areas without reception. The optimization of user data caching and transport is the main functionality of Smart Caching.