TLServer Password Handling
Administrator's Password : See Explanation below
Username/Password Entry
Username: If you make changes to the Username, the new username will take effect. The directory that contains the PC5 file of this user will also be renamed to the new name. However, renaming of Administrator is not allowed and is prohibited by the program.
Password: Enter the desired password for this user. You will be prompted to re-enter the password to confirm. When a user try to access the PLC using TRiLOGI he will need to supply the matching Username/Password pair to gain access. Make sure you don't leave without defining the password, otherwise anybody will be able to gain access to the PLC if he knows the username.
Access Level: Click on one of the 3 radio buttons to select the access level assigned to this particular user. TLServer allows you, the Adminstrator, to control what the user is allowed to do to the PLC when he/she log-in. Only three access levels are allowed, as explained below:
- Programmer: Obviously, if the user is a programmer debugging your PLC's program he must have full access to the PLC, including the ability to transfer a new program to it.
- User: A "User" can access the PLC to monitor the variable or control the I/O such as turning ON/OFF certain devices. However, "User" will not be able to transfer program to the PLC.
- Visitors: Occasionally you may want to allow some people to view the I/O logic state or internal variables, but not to allow them to affect the normal running of the PLC. Assigning the person a "Visitor" access level will restrict him from controlling the I/O at all. The only thing a "visitor" can do is to perform on-line monitoring without being able to force-set or force-reset any I/O.
When you log in to the PLC using TRiLOGI you will be prompted to enter the Username/Password pair. The Username will be matched by the TLServer and the corresponding access level is fed back to TRiLOGI which will will then control the operation that a user can do according to the access level defined here. Future client programs will also observe the access level rule.
It is assumed that only the Administrator has the right to access the user configuration dialog. Hence when you first click on the "Configure Users" button you will be asked to enter the password for the Administrator. This serves to prevent a casual user from making changes to the password and the access level and affect the security of the PLC, which may be accessible from the Internet. However, this is by no means a high security deterence. An experienced user can neutralize your access password, if he is already physically present at your PC that runs the TLserver. (Afterall, if a person can break the lock and enter your premises, what is there to stop him from deleting a few files here and there?)
If this is the first time you run the TLServer after installing TLServer, the default Administrator password is an empty string. Hence you should just pressed <Enter> at the password field to gain access to the user-configuration program. You can change the Administrator's password later.
