Password can be assigned to a license in order to restrict the ability to check out, or even see the license.

Settings in NetSim License Server:

In NetSim License Server, specify

 _password = password-string

in the license in the NetSim License server system.

Settings in Client systems running NetSim Software:

If specified, a license password restricts access to this license to requests which have specified the same password-string. The password-string is specified with the RLM_LICENSE_PASSWORD environment variable in the NetSim client system, or in the RLM web interface for viewing licenses and accessing the license.

Note that the license password does not factor into the license signature, and hence can be changed at any time after the license is signed. Also note that license passwords only work with served licenses, not node-locked or single licenses in local license files. 

Also note that if you do assign a password to a license, and the NetSim License server fails to supply the correct password, the server will return a "License Server does not support this product" error (status -18)" when checkout is attempted.

Beginning in RLM v9.2, license passwords can be specified on the ISV line, with the new "password=password-text" option. When specified this way, the password on the ISV line applies to all LICENSE or FEATURE lines for the ISV which follow the ISV line in the license file. If an individual LICENSE line specifies a password, the password from the LICENSE line is used in place of a password on the ISV line

Related Articles:

How to reserve NetSim Licenses for a specific PC/Laptop?

Setup of VPN connectivity to server to run NetSim from home?

How to restrict access to the NetSim license server web interface?