Energy efficient cloud computing for mobile users

移动设备的云计算提供了在移动设备上执行复杂计算任务的机会，方法是通过无线网络连接将其卸载到功能更强大的服务器(云)。云计算系统设计者的目标包括能效(所有系统组件：无线设备、无线通道和基础设施以及云服务器)、延迟和执行时间、用户效用和/或满意度、资源利用的公平性等。在本提案中，主要关注所有系统级别的能效及其对其他目标(如延迟最小化或公平性)的影响。 虽然能源使用可能一直是移动云计算的主要目标，但由于移动设备电池充电的寿命较短，其研究通常是在某些理想化的假设下进行的，以便于分析。我们建议在现实条件下研究移动云卸载(MCO)，其中包括(A)与自私代理(移动用户、服务器提供商、基础设施运营商等)竞争的环境。(B)任务期限等硬限制的存在，以及(C)移动云计算基础设施的放置和供应，例如用于车载无线通信的云小程序和路侧单元。多个移动用户对相互依赖的任务的分流导致多个系统瓶颈(如无线通道、接入点或云服务器)的竞争行为和策略决策。摆脱中央协调，并在上述现实约束下将决策责任从基础设施设计者/操作员转移到个人用户是本提案的中心主题。在MCO中，移动用户可能决定不将其任务卸载到云中(例如，由于违反任务截止日期)，而另一个能够满足所有硬约束的用户可能会决定卸载，因为这将通过使用系统能量来执行其任务来增加其效用。在云服务提供商方面，自私行为表现为努力实现利润最大化和能源消耗最小化，但合作(在博弈论意义上)也是如此，如果它能够带来更好的服务和更多的移动用户参与，从而更好地利用提供商。将决策责任授权给单个代理导致系统资源的利用不是最优的。这项提议的重点是研究自私行为造成的系统效率低下，通过设计调度和定价政策减轻其影响，以及设计和分析用于建设和供应移动云计算所需基础设施的高效算法。

Cloud computing for mobile devices offers the opportunity of performing complex computational tasks on a mobile device by offloading them to more powerful servers (the cloud) through wireless network connections. The objectives of cloud computing system designers include energy efficiency (at all systems components: the wireless device, the wireless channel and infrastructure, and the cloud servers), latencies and execution times, user utility and/or satisfaction, fairness in resources utilization, etc. In this proposal, the main concern is energy efficiency at all system levels, and its effects on other objectives (such as latency minimization or fairness). Although energy use has probably been the primary objective in mobile cloud computing, due to the short life-time of a mobile device battery charge, its study has usually been done under certain idealized assumptions that facilitate analysis. We propose to study mobile cloud offloading (MCO) under realistic conditions that include (a) a competitive environment with selfish agents (mobile users, server providers, infrastructure operators, etc.) trying to optimize their utility, (b) the existence of hard constraints such as task deadlines, and (c) the placement and provisioning of mobile cloud computing infrastructure, such as cloudlets and Road Side Units for vehicular wireless communications. The offloading of interdependent tasks by several mobile users leads to competitive behaviour and policy decisions at several system bottlenecks, such as the wireless channels, the Access Points, or at cloud servers. Getting rid of central coordination and moving the decision responsibility from the infrastructure designer/operator to the individual user under the realistic constraints mentioned above is a central theme of this proposal. In MCO, a mobile user may decide not to offload its task to the cloud (e.g., due to task deadline violations), while another user who can meet all hard constraints may decide to offload, since that would increase its utility by using system energy to execute its task. On the side of cloud service providers, selfish behaviour is displayed in an effort to maximize profits and minimize energy consumption, but so does cooperation (in the game-theoretic sense), if it can lead to better services and larger mobile users participation, and, therefore, better provider utility. The delegation of decision responsibility to individual agents leads to suboptimal utilization of system resources. This proposal is focused on the study of system inefficiencies due to selfish behaviour, the alleviation of their effect through the design of scheduling and pricing policies, as well as the design and analysis of efficient algorithms for the building and provisioning of the infrastructure needed for mobile cloud computing.