This paper proposes a specification of Role Based Access Control policies to solve the dynamic access control for the Web based library management system.According to the NIST unified Role Based Control model standards

a Role Based Access Control meta-model is constructed based on the analysis of the affecting factors of the access control management and the access control requirements for the Web based library management system.Based on this meta-model

a compact Role Based Access Control XML policy specification language framework is proposed.The results show that this policy specification language framework can represent the access policies for library materials in dynamic environment

and improve the security to access the materials in the Web based library management system.