摘要： 构建了基于远程访问拨号接入用户服务（RADIUS）的认证、授权和计费系统。试运行表明RADIUS 原有实现方式的大运算量和频繁的文件读写操作降低了用户认证效率，且存在系统管理员盗用用户账号的风险。改进了RADIUS 实现方式，降低了认证程序实现复杂度，提高了用户认证效率，同时降低了密码泄漏风险。对于广泛采用RADIUS 的安全应用是很好的借鉴。

关键词: 远程访问拨号接入用户服务；网络安全；认证；授权；计费

Abstract: A remote access dial in user service (RADIUS) authentication, authorization and account system is constructed. Two problems emerge during the test run. One is the low authentication efficiency during the user authentication; the other is the misappropriation of user accounts by RADIUS administrators. The analysis and improvement are proposed to reduce the complexity of authentication program, enhance the user authentication efficiency and avoid the misappropriation

Key words: Remote access dial in user service (RADIUS); Network security; Authentication; Authorization; Account