http://www.lijyyh.com/2013/07/radius-configuring-radius-server.html
http://tec1021.pixnet.net/blog/post/28639573-%E8%BC%95%E9%AC%86%E6%9E%B6%E5%A5%BDradius%E4%BC%BA%E6%9C%8D%E5%99%A8~
http://www.slideshare.net/basimaly1/introduction-to-diameter-protocol-part1
http://searchsecurity.techtarget.com/definition/RADIUS
http://www.netexpertise.eu/en/freeradius/daily-accounting.html
https://www.howtoforge.com/authentication-authorization-and-accounting-with-freeradius-and-mysql-backend-and-webbased-management-with-daloradius#-setting-up-web-management-with-daloradius
