In　today＇s　Internet　era,　the　development　of　application　software　gradually　becomes　mature,　which　makes　people＇s　working　mode　also　change　accordingly.　Applications,　however,　the　scale　is　expanding　constantly,　make　the　internal　structure　of　software　is　more　complex　than　before,　the　application　of　the　environment　has　become　more　open,　causing　the　site　to　be　attacked　events　occurred　frequently,　makes　the　credibility　problem　of　software,　especially　in　security,　reliability,　availability,　and　so　on　several　aspects.　At　present,　the　research　on　software　credibility　is　mainly　based　on　application　demand　and　software　behavior,　which　are　closely　related　to　software　credibility.　Under　this　architecture.　However,　too　many　researchers　focus　on　whether　the　application　system　meets　the　application　requirements,　and　do　not　focus　on　the　credibility　before　the　system　design.　Therefore,　this　paper　mainly　takes　the　behavior　statement　as　the　entry　point　to　study　whether　there　are　some　untrustworthy　factors　before　the　system　design.　©　Published　under　licence　by　IOP　Publishing　Ltd.