Final answer:
The technology that combines both authentication and authorization into a single function is TACACS+, which provides extensive control over access to network devices and separates authentication, authorization, and accounting services.
Step-by-step explanation:
The technology that combines authentication and authorization services into a single function is TACACS+ (Terminal Access Controller Access-Control System Plus). TACACS+ is a protocol that provides access control for routers, network access servers and other networked computing devices via one or more centralized servers. It separates authentication, authorization, and accounting (AAA) services, which allows more control over which users are granted access to which services. On the other hand, RADIUS (Remote Authentication Dial-In User Service) is more commonly used for network access and is less flexible as it combines authentication and authorization into a single step. LDAP (Lightweight Directory Access Protocol) is primarily used for directory services and not specifically for network authentication or authorization. Kerberos is a network authentication protocol designed to provide strong authentication for client/server applications by using secret-key cryptography.