Which authentication method is NOT typically used by PAN devices?

The authentication method not typically used by Palo Alto Networks (PAN) devices is OAuth. While PAN devices integrate well with various authentication protocols to ensure secure access and management, OAuth is primarily designed for delegated access, often in a web application context, and focuses on granting limited access to resources without sharing credentials.

In the case of PAN devices, RADIUS (Remote Authentication Dial-In User Service) and TACACS+ (Terminal Access Controller Access-Control System Plus) are commonly used for network access control and user authentication. LDAP (Lightweight Directory Access Protocol) is also widely utilized for querying and modifying directory services and is frequently involved in centralized user directory services for authentication purposes.

Due to its fundamental purpose and application, OAuth does not fit the traditional authentication roles needed for network devices like those from Palo Alto Networks, making it the correct choice as the method not typically employed.