Initiator: the participating entity that initiates the handling of the information. The RoleIDCode will be (110156, DCM, "Initiator Role ID").

Source: the participating entity from which the information originates. The RoleIDCode will be (110153, DCM, "Source Role ID").

Destination: the participating entity to which the information is directed. The RoleIDCode will be (110152, DCM, "Destination Role ID").

Physical media: the participating entity is tangible storage with a unique persistent identity. E.g., a USB drive with a partition ID, a CDROM with a volume label, or printed film with a physical label. Include (110154, DCM, "Destination Media") or (110155, DCM, "Source Media") as a RoleIDCode value. The MediaType element will also be present.

Digital media: the participating entity is a digital resource with a unique persistent identity. E.g., an email message with [RFC 5322] Message-IDs, cloud storage objects with unique URIs, or network file shares with specific paths. Include (110154, DCM, "Destination Media") or (110155, DCM, "Source Media") as a RoleIDCode value. The MediaType element will also be present.

Network access points: the participating entity is a network endpoint with a unique identity. E.g., a DICOM Application Entity with an AE Title and/or an identifier for the network access point. Include (110153, DCM, "Source Role ID") or (110152, DCM, "Destination Role ID") as a RoleIDCode value. The MediaType, MediaIdentifier, and NetworkAccessPointID elements may also be present.

Applications: the participating entity is a service that cannot provide unique identification for individual transactions, messages, or media items. E.g., clipboard managers (which cannot uniquely identify clipboard contents), messaging systems that lack message-by-message tracking, and some email systems that do not provide Message-IDs. Include (110150, DCM, "Application") as a RoleIDCode value. Applications may be identified by values in other elements, e.g., mailto://person@example.com, process name, or service identifier.

Person: the participating entity is someone associated with a persistent identity provided by an organization. E.g., a physician with provider ID or a hospital staff member with a network login. Include (110153, DCM, "Source Role ID"), (110152, DCM, "Destination Role ID"), or (110156, DCM, "Initiator Role ID") as a RoleIDCode value. Person participants may be identified by values in other elements, e.g., UserID or AlternativeUserID.