To cope with frequent changes and functional additions of operation and support systems (OSSs), a guideline of OSS's architecture and development methods is needed. TeleManagement Forum has provided Next Generation Operations Systems and Software (NGOSS) technologyneutral architecture (TNA), which describes major concepts and architectural details of the NGOSS architecture in a technologically neutral manner. The TNA can be mapped onto technology-specific architectures (TSAs) using specific technologies such as Extensible Markup Language, Java, and Common Object Request Broker Architecture. Web Service, a distributed and service-oriented computing technology, can be also applied to NGOSS TSA. In this paper, we provide a design and implementation of Web Services-based TSA in accordance with the architectural principles of TNA and the performance evaluation of our proposed system. Our work can be used as a guideline for anyone planning to develop a Web Services-based NGOSS TSA.