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CAS is a full-featured open source single sign on service that has been deployed at universities, non-profits, non-government organizations, governments, small businesses, and large corporations in many countries including the United States, Canada, France, Spain, United Kingdom, Portugal, Turkey, Italy, Germany, China, India, Japan, Australia, and New Zealand.
Single sign on servers allow integrated applications to share a single sign on session, meaning users are only required to log in once, and they are logged into multiple applications without those applications ever seeing the user's password. Using a single sign on server reduces security risks and allows for easier integration with 3rd party or external services.
What is Jasig?
Jasig is a non-profit consortium of educational institutions and commercial affiliates that sponsors open source software projects for higher education. Jasig organizes conferences in support of open source software planning, design, development, and implementation. Jasig currently sponsors the uPortal and Central Authentication Service (CAS) projects, and is currently incubating potential projects like Bedework, OpenRegistry, and various portlets.
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CAS supports the CAS1 and CAS2 protocols allowing for simple single sign on, as well as proxy authentication. Proxy authentication allows an application, such as a portal, to access additional resources or applications (such as grades) on your behalf without your password and a secure and controlled manner. The addition of SAML 1.1 allows for the exchange of attributes between the CAS server and CAS clients. Partial SAML2 support allows for integration with Google Apps for Education, allowing universities that have deployed CAS to take advantage of institutional GMail.
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