Through the use of SIS locks and keys, DeltaV provides security mechanisms at the SIS parameter, SIS parameter field, and SIS function levels. At the parameter and field levels, the DeltaV system allows you to control which users can write to specific parameters and parameter fields at runtime. At the function level, the DeltaV system allows you to control which users can perform certain functions, for example, downloading the configuration.
SIS fields, SIS parameters, and SIS functions are assigned to locks through DeltaV Explorer (under System Configuration\Setup\Security). To be able to write to the field or parameter or perform the function, the logged-on user must have been assigned the key to the lock. Key assignments are configured in DeltaV User Manager.
User span of control and access privilege is further defined by the plant area assignments. SIS modules can coexist with control modules in an area.