Optimization And Application Of IDEA Algorithm Based On Android Platform

September 2007, Google published Android smart phone system. It develops rapidly on a mobile terminal equipment, and the problem of leakage of information security is becoming more and more. Its built-in open source SQLite database in order to meet the mobile device access speed and memory usage rate performance requirements, does not provide encryption function, but SQLite database designers still reserved encryption interface.IDEA is the International Data Encryption Algorithm, was founded in 1990 by the Swiss federal institute of technology, X.J.Lai and Massey’s Proposed Standard Algorithm, called the PES(programs Encryption Standard). Lai and Massey in 1992 improved to strengthen its ability to resist the analysis of the difference, then changed its name called the IDEA. IDEA’s design idea is to use a 128- bit key length for 64 bit block data based on "hybrid algorithms on different algebraic groups" transform operations. Because of their large key space, the computing speed is fast, high security and encryption process in the hardware and software implements easily and quickly, makes its application range is becoming more and more widely.This article main research content is the optimization and application of the standard IDEA key extension algorithm. First analyzes the IDEA of key extension algorithm is insufficient, lead to weak key class, greatly reduce the key space. On this basis, the use of ARX structure is thought to optimize the IDEA of sub-key extension, AR key extension algorithm is proposed, through the experimental analysis shows its key generation effect, and proved its security and efficiency.Second, AR key algorithm is applied to the IDEA in the process of encryption, namely AR_IDEA encryption algorithms, modify SQLite’s source code, definition SQLite encrypted macros, achieve its encryption interface function, encapsulation AR_IDEA encryption algorithm, achieve the function of database encryption.Finally, analyze time limit management system for telecom projects on Android platform including the functional requirements, and data storage security demand, hierarchical design and data security classification, build the telecom APP architecture plan, apply the studying result to the system APP, passed the safety testing.