What is Shibboleth?
Shibboleth is an open source product that enables an organization-spanning (federated) authentication and authorization for web applications. Thus, Shibboleth is an essential component of Federated Identity & Access Management and is primarily used in federations of universities, research institutes, authorities and large companies.
Based on the standard SAML (Security Assertion Markup Language), Shibboleth enables Single Sign-On (SSO), i.e. a user has to authenticate him- or herself only once in order to access multiple services within the federation.