单点登陆 - CAS

CAS is an authentication system originally created by Yale University to provide a trusted way for an application to authenticate a user.   CAS is an enterprise Single Sign-On solution for web services. Single Sign-On (SSO) means a better user experience when running a multitude of web services, each with its own means of authentication. With a SSO solution, different web services may authenticate to one authorative source of trust, that the user needs to log in to, instead of requiring the end-user to log in into each separate service.        

• CAS1 The Central Authentication Server (CAS) is designed as a standalone web application. It is currently implemented as several Java servlets and runs through the HTTPS server on secure.its.yale.edu. It is accessed through three URLs described below:
  • the login URL,
  • the validation URL,
  • the optional logout URL.    
• CAS2     实现：
  • CAS Web APP 使用 SSL
  • 对于各个APP， 需要修改 web.xml 文件来配置 servlet 过滤器