To meet the demand for huge bandwidth created by the multimedia communications revolution, there is an urgent need to dramatically upgrade the existing telecommunications infrastructure. In today's infrastructure, fiber-optics is used in point-to-point transmission links, with all networking and services functions done electronically. To upgrade such an infrastructure in a cost-effective way, Wavelength Division Multiplexing (WDM) technology may be used to transmit multiple optical channels per fiber. This way, network capacity may grow in response to increased demand. In addition, with the reconfigurability of WDM networks, network configuration may adapt in response to changing traffic patterns. To ensure successful deployment and operations of WDM networks, it becomes essential to have a comprehensive network control and management system which is versatile, robust, and scaleable. In this paper, we describe a network control and management system prototype developed under the Multiwavelength Optical Networking (MONET) project funded by the US government's Defense Advanced Research Project Agency. The prototype system provides configuration, connection, fault, and performance management functionalities for reconfigurable WDM all-optical networks. The design of the prototype system follows the TMN logical layered architecture, and it is implemented on a fault-tolerant, CORBA-compliant distributed object computing platform which facilitates robust and scaleable operations.