Dedicated IT systems are increasingly being used for interfacing with external companies to make cooperative working relationships between businesses more efficient. Of course, it must be assured that only authorized persons get access to sensitive data. Federated identities are well-suited for collaborative work between organizations that are administratively independent, so that redundant user accounts are not created. The cooperating partners establish “circles of trust”. The SAML (Security Assertion Markup Language) standard is generally used for this purpose. With SAML authentication, it is sufficient if the user authenticates to a certain identity provider (IdP) once to gain access to every server that is a partner to this IdP.