the conc9pts and approaches relating to information security among the course of development of the ia are introduced . for example, reference monitor ( are ), reference validation mechanism ( rvm ), trusted computing base ( tcb ), security model, tcsec, cc, iatf fritsa, etc . chapter 2 analyzes the time and space property " of information security 第一章对信息保障的历史进行回顾,介绍在信息保障的发展历程中有关信息安全的概念和方法,如:引用监视器(rm)、引用确认机制(rvn)、可信计算基(tcb)、安全模型、tcsec、cc、iatf、fritsa等。