CCODR: Routing optimization for DTN-based space networks in congestion control

Abstract

Interplanetary Network (IPN) is divided into restricted networks because of the harshness of the network environment. Delayed Tolerance Network (DTN) is one of the approved limited network solutions. The static network topology model can't be used for DTN networks due to the frequent interruption of links. In the DTN network, the Contact Graph Routing (CGR) algorithm is widely used. The CGR algorithm is a local optimal routing algorithm. However, due to the shortcomings of the local routing algorithm, the EAODR algorithm is proposed. First, the Modified Temporal Graph (MTG) model is proposed to represent the dynamic topology of the satellite. Second, the global routing algorithm is proposed. But the interplanetary network, the link through the frequency and the link quality is bad, so to minimize the packet loss ratio has become the satellite DTN network key. We improved the Earliest Arrival Optimal Delivery Ratio (EAODR) algorithm, we will predict the congestion rate according to the satellite the history of the queue change rate to avoid congestion. When the entire network congestion is serious, we can take the packet dropping strategy. Discarding packets with low arrival ratio, to ensure the arrival ratio of the whole network. We base Congestion Control Optimal Delivery Ratio (CCODR) routing algorithm on the MTG model. Our results show that we can reduce the delay by CCDOR compared to EAODR.