Study On Short Signature Algorithm And Its Application In Mobile Cloud Computing

As the popularity of mobile terminals which are represented typically by smartphones and tablet computers, the Mobile Internet comes into being. However, the mobile terminals’ storage, computation and other resources are constrained so that the Cloud Computing(CC) is introduced as a new computing model to solve the finiteness of mobile terminals, resulting in the production of the advantage combination of Mobile Internet and Cloud Computing, namely Mobile Clouding Computing(MCC). As a super computing mode, Mobile Cloud Computing enables users to access the opportune computers and storage system in the light of their requirements and gain the required resources and services whenever and wherever possible, besides, the users can implement data exchange commodiously through Mobile Internet, thus reducing the requirements of mobile terminals’ performance, which makes the rapid development of Mobile Internet.Although Mobile Cloud Computing is introduced to solve the limited resources of the mobile terminals, the data has been stored in the cloud ending by monopoly enterprises which only offer commercial credit guarantee, hence the users have the ability to control the data in the "cloud" side any more. And if the malicious users access the cloud, it will bring about a great threat on the security of the data stored in the cloud. Therefore, how to solve the security problems of users’ access and data storage in Mobile Cloud Computing has become a research hotspot. This paper concentrates on the improvements of the Mobile Cloud Computing security issues in authentication access protocol.In this thesis, at first, we propose a certificateless short signature algorithm which has the following characteristics. Firstly, there is no pairing operation in signing phrase and only involves two pairing operations in verifying phrase, what’s more, the signature length is reduced to 160 bits which means higher computational efficiency; Secondly, user’s private key is bounded with his/her public key, so the public key replacement attack is avoided, furthermore, malicious KGC attack is hardly to carry out. Thirdly, the proposed scheme is proven secure against existential forgery of adaptively chosenmessage attack in random oracle model; Finally, we provide a practical method for simulating and evaluating short signature algorithms based on pairing operations to prove that the proposed algorithm has the strong security and high efficiency.Based on the proposed certificateless short signature scheme, we improve the security of the authentication protocol based on open identity(Open ID) in the mobile cloud computing services. Then we put forward a new user access protocol, which is simple and owns low computational complexity, with features such as the identity anonymity, mutual authentication, non-reputation and session key establishment. It provides user with higher access efficiency and security guarantees.