CASA_auth_token is an authentication token infrastructure with support
for multiple authentication mechanisms with an emphasis on providing a
scalable single sign-on solution.

A key feature of CASA_auth_token is that its authentication tokens
contain identity information about the entity being authenticated. This
information contained in the tokens is configured on a per-service
basis. Because of this feature, we say that CASA_auth_token projects an
"Authenticated Identity".

The CASA_auth_token_client package contains the necessary library and
configuration files for client applications to obtain authentication
tokens.