Siemens Industry Online Support
Siemens AG
Entry type: FAQ Entry ID: 21979054, Entry date: 03/11/2019

Why, when implementing SIMATIC Logon, is there a user already logged on after starting WinCC RT / PCS 7 OS or other SIMATIC applications?

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SIMATIC Logon uses a so-called "Single Sign-On" procedure for user identification. With this a single logon is valid for all applications.

SIMATIC Logon uses the so-called "Single Sign-On" as authentication procedure.

If a user logs on via SIMATIC Logon for a SIMATIC application (like STEP 7, for example), then that logon is valid for all applications that also use SIMATIC Logon. This account remains open as long as not all SIMATIC Logon applications are terminated, even if an application is opened again. This procedure is identical to the Windows authentication procedure.

A use logs on via SIMATIC Logon with his/her logon data and open the logon applications "Alpha" and "Beta". After a certain time he/she closes the application "Alpha".
If he/she opens "Alpha" again, he/she is already logged on with the corresponding logon data. A new logon is required only after "Alpha" and "Beta" have been closed at the same time.

This is a system feature to prevent unnecessary new manual logons.

Additional Keywords
"Single Sign On", Logon, Login, Logout, Authentication, Authorizing, Account, Password

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