An mDL can potentially perform as a cryptographic token for physical access to buildings, rooms, parking garages, and other secure areas, similar to how smart cards and RFID tokens are currently used. Access to secure areas is managed by physical access control systems (PACS), which consist of readers deployed at the secure-area entry points with localized actuators that unlatch doors or open gates. The readers and actuators are controlled by a centralized computer/server that hosts the PACS software and database. The database contains access control lists (ACLs); usernames, identifiers, and user privileges; and token information (e.g., an mDL or portions thereof), all of which are entered into the PACS database during a pre-registration or enrollment process.
The process could look like the following: a mobile device with an mDL is held up to an entry-point mDL reader, a communications session is established, and mDL identifiers read from the mDL are used to look up the identifier in an ACL to determine whether the mDL holder has previously been granted access to the entry point.
