Research Of Disruption-tolerant Network’s Network Layer Protocol

With the continuous improvement of science and technology and continuous innovation of technology, satellite networks are more and more put into the practical application. In the next generation Internet construction, satellite communication network is an important component. However, the satellite network features link delaying, high biting error rate, link-state changing frequently and the end-to-end path may being long time not connect etc. Because such characteristics do not meet the prerequisite assumption about the network characteristics of the standard TCP/IP protocol, the standard TCP/IP protocol application cannot be used in the satellite communication network. In order to make the satellite network blend in the next generation Internet construction, which needs to study the network protocol that is suitable for the characteristics of satellite communication network. This article firstly introduces the advantages, disadvantage and typical applications of satellite communication networks and existing satellite communication networks. Then introduces some key technologies and features of Network protocol that are presently used in the satellite communication network,including the CCSDS protocol and Bundle protocol. Finally according to the standard TCP/IP protocol, analyzes the existing problem and performance limitations of its direct application to satellite communication network in detail.According to the problems which exist in the use of TCP/IP protocol in the satellite communication network environment; this paper proposes a network protocol named DTN-IP protocol that is suitable satellite communications network. The protocol adds the assessment and use to the node location information, and uses data storage mechanism, in order to adapt to the characteristics of satellite link intermittent connectivity and a period of time there is no end to end link. The proposed network layer improvement protocol fully takes into account the valuable time of network connectivity, avoids large amounts of information interacting link state, reduces overhead signaling, raises the probability of data packets delivering successfully.According to the proposed improved protocol, this paper also designs a demonstration platform, and makes programming realization on the Linux operating system. The proposed scheme describes in detail the composition of demonstration platform and specific protocol implementation methods, and designs the intuitive visual operation interface. In view of the overall scheme, design multiple experiment scenes that can directly reflect the pros and cons of performance, and make comparative analysis of the experimental data for each scenario in detail, and then verify the integrity of the platform solutions and the performance advantages of the proposed improved protocol.