The Design And Implementation Of Several Modules Of The Network Management System In Converged Satellite And Terrestrial Networks

The converged satellite and terrestrial networks have the advantages of wide coverage in satellite networks and high transmission speed in terrestrial networks, and have the complementary advantages of the both. Such networks can provide users with comprehensive, integrated service experience, and they also represent one of the development directions of the next generation communication systems. However, compared with the terrestrial networks, the converged satellite and terrestrial networks have the characteristics of high latency in satellite channel, higher error ratio and limited resources, coupled with the large scale and the strong heterogeneity, etc. These characteristics result in the higher requirements of the Network Management System (NMS) for the converged satellite and terrestrial networks. In order to ensure such networks work stably, efficiently and safely, we need to develop its NMS.This dissertation introduces the research status and development trends of the NMS in the converged satellite and terrestrial networks, and summarizes the NMS and authentication subsystem. Because the SNMP (Simple Network Management Protocol) and RADIUS (Remote Authentication Dial in User Service) have the advantages of simplicity, easy realization, low requirements for processing ability and less occupation of bandwidth, they are suitable for the converged satellite and terrestrial networks. Therefore, we choose SNMP and RADIUS protocol as the management protocol and the authentication protocol of this system, respectively.This dissertation mainly completes the works as follows:(1) Based on the project demand for the NMS, this dissertation completes its NMS function partition and design. On this basis, it completes the software design of the performance management module, the security management module and the agent module of the NMS.(2) For alleviating defects and the function enhancement of both SNMP and RADIUS protocol when applied to the converged satellite and terrestrial networks, this dissertation improves SNMP by changing the encoding, simplifying SNMP and the prefix of the object identifier, and prioritizing the object identifier, etc. We then modify and enhance the transport mechanism and the security policy of RADIUS protocol. With the modification and enhancement, SNMP and RADIUS can be adapted to the converged satellite and terrestrial networks better.(3) This dissertation makes a description and a comparison of the NMS development tools. By considering the project requirements, we finally choose SNMP++, NET-SNMP and FreeRadius development kit as the development tools of the manager, the agent and the authentication server, respectively. Accordingly, we develop the performance management module, the security management module and the agent module by C/C++ and MFC (Microsoft Foundation Classes).(4) Through designing and building the test platform, we test the performance management module, the security management module and the agent module. The results show that the developed NMS in this dissertation is preliminarily valid when it is applied to the converged satellite and terrestrial networks.