在移动计算环境中，能够将智能终端上的计算任务卸载到其他资源上运行的计算卸载技术可增强终端能力、提高应用服务质量、改善用户体验。然而，现有计算卸载技术难以保证智能终端在移动过程仍然能够获得稳定、高效和低开销的计算卸载服务。本项目提出了在移动云计算环境中支持节点移动性和任务迁移的计算卸载体系结构，在计算卸载任务的划分、分配阶段和运行阶段给出了如何支持节点移动性和任务迁移的思路和方法：(1)提出了根据终端移动性和任务组件的潜在切换需求来对任务进行划分和分配，从而减少潜在切换开销的思路和方法；(2)给出了智能终端在有基础设施计算环境和移动设备云中进行任务迁移时的切换管理决策框架和相应的切换判决准则和切换算法。这些思路和方法将通过原型实验系统和应用实例进行验证，并通过仿真实验对其性能进行深入的研究。本项目的研究将为资源受限的移动终端在移动过程中获得稳定、高效和低开销的计算卸载服务奠定基础。

Computation offloading, or cyber foraging, is a solution to augment the capabilities of resource-constrained smart devices by migrating computation to more resourceful surrogates, and thus to augment the ability of the devices, to improve the quality of services of applications and the quality of experiences of users. However, existing technologies and researches on computation offloading cannot guarantee that the devices will receive stable,efficient and low-cost offloading services while they are roaming around within mobile cloud computing environments. This proposal put forward an offloading framework and some mechanisms during the task partitioning,allocating and migrating procedures to support the mobility of smart devices and the migration of task components between resources: (1) Some algorithms were suggested to partition offloaded tasks and to allocate them to surrogates proactively taking into account the mobility of the devices and potential migration of task components. (2)For both infrastructure network-based cloud computing environments and mobile device clouds, a handoff management framework, as well as some fundamental handoff criteria and algorithms,will be investigated to support task migration between resources. All the mechanisms and algorithms will be verified by prototype systems and real instances, and the performances of the algorithms will be investigated deeply via simulations. The researches in this proposal will be very important and fundamental to help roaming smart devices to get stable, efficient and low-cost offloading services.