Distributed Computing in a Cloud of Mobile Phones

For the past few years we have seen an exponential growth in the number of mobile devices and in their computation, storage and communication capabilities. We also have seen an increase in the amount of data generated by mobile devices while performing common tasks. Additionally, the ubiquity associated with these mobile devices, makes it more reasonable to start thinking in a different use for them, where they will begin to act as an important part in the computation of more demanding applications, rather than relying exclusively on external servers to do it. It is also possible to observe an increase in the number of resource demanding applications, whereas these resort to the use of services, offered by infrastructure Clouds. However, with the use of these Cloud services, many problems arise, such as: the considerable use of energy and bandwidth, high latency values, unavailability of connectivity infrastructures, due to the congestion or the non existence of it. Considering all the above, for some applications it starts to make sense to do part or all the computation locally in the mobile devices themselves. We propose a distributed computing framework, able to process a batch or a stream of data, which is being generated by a cloud composed of mobile devices, that does not require Internet services. Differently from the current state-of-the-art, where both computation and data are offloaded to mobile devices, our system intends to move the computation to where the data is, reducing significantly the amount of data exchanged between mobile devices. Based on the evaluation performed, both on a real and simulated environment, our framework has proved to support scalability, by benefiting significantly from the usage of several devices to handle computation, and by supporting multiple devices submitting computation requests while not having a significant increase in the latency of a request. It also proved that is able to deal with churn without being highly penalized by it