| The rapid development of communication technology promotes the social development, and provides people with great convenience. As basic network, the transmission network will be responsible for encapsulating the traffic signals in different service network, supporting management network and other network into a specific frame format. So as to provide an information transfer channel, and realize transparent transmission of long distance and high-capacity service between nodes. Optical transport network(OTN) is the best option to transfer bandwidth and high-capacity granularity service. It is based on wavelength-division multiplexing technology, and possesses the powerful section overhead and management ability of SDH. OTN is mainly located in the national trunk transmission network, provincial / regional trunk transport networks and metro / local transport network. With the rapid growth of data traffic, OTN is extending to the metro aggregation and access network. Therefore, OTN has become the core part of transport network.Optical transmission networkconsists of network element(NE) which is distributed in different geographic locations, all network elements in OTN network are managed uniformly in the Element Management System(EMS) by telecommunications operators. With the increasing of network size and communication security risk, the management of NE device in OTN transport networks is suffering greater challenges. On the one hand, the increase of NE number will deplete more IP resource, at the same time, the communication between EMS and NE device will increase. On the other hand, the communication between EMS and NE is based onTCP/IP protocol, while TCP/IP protocol did not take network security issues into account at early stage, leading to the safety of NE without indemnification. For the big size and core part of OTN, a security problem will lead to serious consequences. Therefore, the security management and maintenance of NE in OTN are concerned by telecommunications operatorsand equipment manufacturers.The research content of this thesis comes from the requirement of the operator to improve the security performance of OTN network management, which is mainly summarized as two parts. The first part is about the study of OTN equipment management system, including its overall structure, communication technology and management methods. The problems need to be solved about management safety performance of major used gateway network element to improve engineer are analyzed. In this paper, by improving of original management mode, a enhancement gateway network element management mode is implemented, which almost does not change the original network and can add the security communication protocol between the network element and EMS. The second part is about the studies of the framework of SSH protocol, the communication process, the knowledge of cryptography and other functions. The SSH protocol is currently more reliable for a security communication based on the application layer. In this paper, the open source version of Open SSH we used between the EMS and the enhancement gateway network elements achieves the function of SSH.In this paper, the above two parts function deployment is completed by the equipment. Based on the improvement management scheme about the network element equipment, through the deployment of secure communication protocol SSH, safety management of equipments is ensured. Also, the functions of Telnet and SFTP are verified in the actual operating environment. |
