Patent ID: 8522333

Claim:
A method for integrating single sign-on (SSO) mechanisms in a client/server system with communication according to the OPC UA protocol and for performing SSO for user authentication in the system, wherein the system includes an OPC UA client which is connected to an OPC UA aggregating server, which in turn is connected to a plurality of subordinate OPC UA servers by means of a communication network, the method comprising: providing, in order to integrate the SSO mechanisms, the OPC UA aggregating server with an SSO component for mapping user legitimation data, which are used in a service call, to identities in a form in which the identities are stored in the plurality of subordinate OPC UA servers; and utilizing, in order to perform SSO with the aid of the SSO component, user legitimation data belonging to a service call to automatically look for corresponding mapped identities and for affected OPC UA servers and, for each match, to call an ActivateSession service in the respective OPC UA server using the mapped identity, after which the data access desired with the user's service call is established.