مدل محاسباتی ابری ناهمگن برای ابرهای هیبریدی A heterogeneous mobile cloud computing model for hybrid clouds

1. Introduction Throughout the last few years, cloud computing (CC) has provided computing solutions to lots of companies, organizations, and individual users in the form of services over the Internet. CC provides on-demand, pay-per-use, and highly scalable computing capabilities for services that enhance the user experience in a transparent way for the user [1]. Meanwhile, with the current exponential growth of mobile devices, there is an emerging concept called mobile cloud computing (MCC) that has erected to integrate CC into the mobile environment [2]. In MCC, user applications are computed in remote clouds rather than in their own mobile devices, providing multiple benefits to the mobile users, such as a longer battery lifetime or a lower processing load. Among the different approaches to MCC, we can bring the computation capabilities closer to the mobile users. This model locates small-scale servers or cloudlets at the edge of the network (e.g., base stations or coffee shops) in order to avoid latency or bandwidth issues CC experiment. This approach is related to novel paradigms such as fog and mobile edge computing and is supposed to be a key aspect in 5G [3, 4]. On the other hand, it needs a periodic synchronization between the edge servers and the cloud, so several questions arise: when should the edge servers upload data to the cloud servers? How will the cloud handle such amounts of data from multiple edge servers located all over the world? How will these systems guarantee consistency (one of the desired properties of a distributed system according to Brewer’s theorem [5])? There are only a few published works related these issues [6, 7] and they are all also theoretical. Besides, this approach has numerous security issues (e.g., authentication, mobility, or access control) [8, 9], and not all companies and organizations will be able to deploy multiple servers at the edge of the network due to the high investment that it entails. For all these reasons, we have developed a heterogeneous mobile cloud computing model that can provide most of the benefits of the fog and mobile edge computing solutions, but it can also be deployed easily and inexpensively by enterprises into their current cloud systems.