Research Of Outer-oriented Database Security Technology

Thecoreofinformationsafetyisthedatabasesafety; researchonencryptionofvitaldataindatabaseis anissuewithimportantlytheoreticalandpracticalsignificance.Forthemoment,data in most of database are not protected by encrypting form, but by using some outsidemethods. There are some other traditional measures, such as access control, fire wall andintrusion detection and so on. However, these measures can not solve all that securityproblems. Thereason is that thedataindatabaseis kept underspecifiedterms.But encryptionaffects the performance of the system deeply so that the practice query applications for thelarge database hardly achieve. Asafe and efficiency highly algorithm must be found to meettheexpectationofpracticeapplication.The main research of this article is the management and operation of the cipher textdatabase. Depthanalysis ofthis paper,basedonorderpreservingencryptionfornumericdata,as well as character-based data encryption methods OPES +, from the viewpoint of thesecuritystrengthandqueryefficiencyof thetwoalgorithms,theencryptionprinciple,process,key technology and frame are developed. After the advantage and the problem of them beingconcluded,an improved encryption method is presented, it is a fusion of barrel-dividingtheory and order-preserving encryption method. In the algorithm the smallest description ruleis introduced, so the time cost of the query is connected to the mount of barrel, it greatlypromotedthequeryefficiencyandthequeryaccuracy.Finally,the experiments are conducted to prove the above algorithms from variousaspects of percentile exposure, incr??tal updatability and overhead of time and space.Queryqualityoftwomethodsiscomparedwithconventionalways,anditoffersdirectionandexperienceformoreresearch.