The Moitree middleware for distributed mobile-cloud computing

Commonly, mobile cloud computing assumes that each mobile device of a user is paired with a user-controlled surrogate in the cloud to overcome resource limitations on mobiles. Our Avatar platform leverages this model to support efficient distributed computing over mobile devices. An avatar is a per-user, always-on software entity that resides in the cloud and acts as the surrogate of the mobile. Mobile-avatar pairs participate in distributed computing as a unified computing entity in such a way that the workload and the demand for resources on the mobiles remain low. This paper presents Moitree, the middleware of the Avatar platform, which provides a common programming and execution framework for mobile distributed apps. Moitree allows the components of a distributed app to execute seamlessly over a set of mobile-avatar pairs, with the provision of offloading computation and communication to the cloud. The programming framework has two key features: user collaborations are modeled using context-aware group semantics - groups are created dynamically based on context; data communication among group members is offloaded to the cloud through high-level communication channels. A prototype of Moitree, along with several apps, has been implemented and evaluated on Android devices and on a cloud running Android x86 avatars.