The concepts and functionalities of customer service management have been analysed. A novel hierarchical representation method of abstract network, logical network, is provided. The structure, attributes and computation of logical network as well as a CSM management model have been studied. An implementation prototype of CSM system is provided. At the underlying layer, CORBA, common object request broker architecture, is used as a supporting environment and for achieving representation, management, update and access of CSM-MIB. At the higher layer, customers are allowed to reassemble the physical network and generate a hierarchical "logical network" through methods of definition, creating and maintenance. Thereby the functionalities of CSM such as agreement, assignment, performance monitoring and reporting can be implemented.