Enterprise management is the task of ensuring that the networks and systems provide the required services with the specified quality of service to the users and other systems. Most enterprise management architectures use agent-manager relationship where the agents, residing on managed network/system elements, provide network/system management information such as alerts or performance measurements to the manager. The manager reacts to these messages by executing one or more actions such as operator notification, event logging, system shutdown, and automatic attempts at system repair. Management entities also poll end stations, automatically or upon user request, to check the values of certain variables. Agents have information about the managed devices in which they reside and provide that information (proactively or reactively) to management entities within one or more enterprise management systems (EMSs) via a network management protocol. The term enterprise management refers to the combined task of network and system management.