Fog for 5G and IoT

6Wireless Video Fog: Collaborative Live Streaming with Error Recovery

BO ZHANG,¹ ZHI LIU,² and S.‐H. GARY CHAN¹

¹ Department of Computer Science and Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong

² Global Information and Telecommunication Institute, Waseda University, Tokyo, Japan

6.1 INTRODUCTION

With technological advances in multimedia processing and wireless networking, live video content can now be streamed to wireless devices over the Internet. To serve geographically distributed clients,¹ the stream is distributed using a cloud, with the wireless clients independently pulling the stream via an access point (AP) or base station. This model suffers from last‐hop scalability problem—as the number of clients served by the AP increases, its wireless bandwidth becomes a bottleneck (wireless broadcasting standard is not yet widely used nowadays). To overcome such limitation and scale up the last‐hop user capacity, the wireless devices may form a wireless fog, where they collaboratively share the live stream they pulled from the AP with their neighbors in a multihop manner via a secondary channel (such as Bluetooth, Wi‐Fi, etc.). In a wireless fog for live video, devices hence donate their resources (computing power, storage, and communication bandwidth) to scale up the system in a cost‐effective manner.

We illustrate in Figure 6.1 a typical live streaming network. The streaming cloud distributes the live stream over the Internet. ...