Whether offloading intensive computations, or data storage, using the cloud for mobile devices does pose questions of security and trust issues. In her article in [80], Kharif outlines the potential pitfalls in using cloud services for mobile devices. Because of the low capacity of mobile device storage, many users are starting to store data such as contacts, calendars and SMS on clouds. However, these cloud services are stated to be vulnerable and users may lose their data if the services go out of business, or simply if the services fail due to technological problems.
Recent examples. For example, in the October of 2009, a large number of T-Mobile Sidekick users discovered that their personal data stored in the mobiles had disappeared due to a server failure [81]. The Sidekick data, such as users’ contacts, photos and calendar appointments, was stored in a cloud service operated by the Microsoft company Danger. Although the majority of users did recover most of their personal data by November, this outage caused many difficulties, and raised many questions about how secure and robust the cloud really is.
Is cloud security applicable to mobile clouds as well? Mobile cloud computing inherits the security threats of conventional cloud computing in cases when the definition of mobile cloud means to connect mobile devices to a remote cloud. In this case, the remote cloud server would be the same as a conventional cloud computing provider, making the general cloud security threats valid. At the same time, mobile clouds present a group of issues that are particular to mobile devices offloading jobs through wireless communication channels. Furthermore, security concerns that are specific to mobile devices such as battery exhaustion attacks [82], mobile botnets and targeted attacks [83] should also be considered.
