Space-Air-Ground Integrated Network Routing Protocol Research

Space-air-ground integrated network is a fusion of space, air and ground, which has achieved the network application scenario by way of interconnection in various levels. Its efficacy contributes enormously to military, civilian, and scientific exploration of space, so the development of space-air-ground integrated network represents the degree of a nation’s information progress accordingly. In response to various communication limitations under ambient conditions, the emerging network architecture(restricted network) under single environmental condition has sprung up. The challenge to complete the interconnection of the network is independent protocol architecture. Different protocols may have different architecture and underlying network transport layer individually, moreover, it is difficult to unify different addressing scheme. Therefore, how to achieve interoperability and efficient routing in various independent network domains has become a hot research spot.This thesis concerns the designing of a space-air-ground integrated network protocol architecture which covers various networks and is able to transmit data in different sub-domains with the combination of the specific network scenarios(space-air-earth integrated network) and the reference of DTN architecture. A bundle layer between the transport layer and application layer is obtained. This design combines storage and routing functions, eventually achieves the cross-border transmission of data, and the shield of the different underlying networks. Due to the physical characteristics of frequent interruption and large delay of space communication, the traditional routing algorithm based on the connected graph in communication process(OLSR, AODV, etc.) can hardly achieve effective data forwarding. In this thesis, CGR-EPI routing scheme has been proposed, that is, the bundle layer routing protocol select appropriate routing in different network. The unified addressing scheme of the entire network’s DTN nodes with the help of URI has achieved late binding of the destination address and overcome the problem of non-operability of DNS during network interruption. Finally, taking into account the consideration that EPI routing algorithm is believed to exhaust network load and can lead to insufficient cache disadvantages easily, a multi replica routing algorithm based on grey prediction is suggested. In this thesis, a method is put forward to tackle this problem, which use the grey prediction theory to predict the position of node’s future location. The results of the algorithm performance simulation and the corresponding routing performance simulation prove that routing algorithms based on position prediction can prevent the routing storm caused by nodes density effectively, improve the packet arrival rate, and decrease the network load.