Shibboleth is standards-based, open source middleware software which provides Web Single SignOn (SSO) across or within organizational boundaries. It allows sites to make informed authorization decisions for individual access of protected online resources in a privacy-preserving manner. This software is a C++ implementation of the Service Provider version 2 component of the Shibboleth can be used in Apache Web servers. The service provider manages secured resources. User access to resources is based on assertions received by the service provider (SP) from an identity provider. WWW: http://shibboleth.internet2.edu/