A security identifier represents a protected resource. Every secured element in the application is given a SID that is unique across the entire application. They are used to secure administrative functions, fields on a screen, organization units, locations, case audits, and programs offered by the organization, including products, and service plans.
The most common type of security identifier is the functional SID, also known as a function identifier or FID. FIDs are used to secure business processes. An example of a function identifier is the FID assigned to the register person business process. Another type of security identifier is the field SID. Field security is used to secure specific information displayed in a field on an application page or set of pages. An example of a field SID is the SID used to secure the particpant bank account balance field.