Guest Editorial Cloud-Based Mobile Media: Infrastructure, Services and Applications

The proliferation of smart phones and tablets have fuelled a new wave of demand for mobile services. Today's users not only expect ubiquitous network connections, but also seek a rich media experience wherever they go and whenever they need. The thrive of mobile media gives rise to a multi-fold of technical challenges. It is hard to sustain satisfactory quality of experience over inherently unreliable wireless links. Large-scale, simultaneous delivery of media contents tends to swamp existing mobile network infrastructure. Moreover, a fundamental gap exists between the resource demands of computationally expensive multimedia applications and the capabilities afforded by battery-operated mobile devices. Recent advances in cloud computing help to bridge this gap. By resorting to the cloud as a reservoir for additional computation and storage, mobile media services can scale better with user demand in an elastic and dynamic manner, at relatively low costs. This new paradigm of cloud-based mobile media introduces various issues: cloud resource provi-sioning and scheduling, media content management, quality-of-service (QoS), user mobility, security, etc. Meanwhile, it opens new avenues. Mobile applications may offload compu-tationally expensive tasks to the cloud. Service providers may pool together statistics of mobile devices at the same region, and leverage such knowledge to improve their media transport and caching strategies. It is the aim of this special issue to report on latest research that explores various aspects of cloud-based mobile media. Through an open call for papers, we received 40 submissions. Fourteen (14) papers were accepted for final publication after two rounds of highly competitive reviews. The final papers were selected on the basis of originality and significance of the technical work, as well as relevance to the theme topic. The papers in this special issue span a wide range of novel algorithms, techniques, applications, and system-level solutions. They naturally fall into two categories: addressing existing challenges or exploring emerging opportunities. The topics covered by the first group of six (6) papers are representative of issues faced by cloud-based media systems. In " Efficient Resource Provisioning and Rate Selection for Stream Mining in a Community Cloud " , Ren and van der Schaar present a mathematical framework for jointly provi-sioning cloud computing resources and selecting media transmission rates. Their formulation strives to strike the optimal balance between energy consumption, classification performance , and application responsiveness. The paper presents an online learning algorithm that does not require knowledge of wireless channel statistics. Its effectiveness …