||Cloud computing is becoming a hot technology areas recently, and it is viewed as the next emerging industry and becomes commercialization even if its concept has been proposed a few years ago. Whether is the public cloud, private cloud,hybrid cloud, application-level logistics cloud, medical cloud, government cloud or education cloud, a variety of services evolve by the technology. Hence, the users can obtain the network service by any kinds of network access devices that are no longer bounded to a personal PC, but multiple hosts provide various services for the users to choose at the same time to get a better service quality than the previous server architecture.Cloud computing centralizes the data on the data center by users to do the distributed processing. Hence, how to prevent the processed data be threatened from the eavesdroppers in the transmission process is an urgent problem needed to be solved for the cloud service providers.
Nowadays,many cryptography algorithms can provide confidentiality and integrity of data.In open system environment of cloud computing,if the user's personal information used to authentication is disclosed and abuses the access privilege will cause the damage situation.For the reason, cloud computing needs a new security mechanism. So the cloud service provider not only needs the capability to self-defense,but also confirms the personal privacy information accessed by the user will not scurry in the cloud. More importantly, the user can transfer the data to other open service platform safely, quickly and seamlessly is the spirit of the cloud.This thesis proposes a secure MapReduce mechanism for the open system environment, which provides the safety data transfer and reliable data integrity verification.