Space communications are characterized by link intermittent connectivity and long link propagation delay. The use of bundle protocol (BP) in space communications has been in debate. An analytical understanding of its performance for reliable data delivery in the presence of link intermittent connectivity, especially with a lengthy link disruption, is quickly needed. In this paper, analytical models are built to estimate the number of transmission rounds (or efforts) caused by the link disruption and the resulting delay in bundle delivery of BP for applications in space communication networks. The models are validated by conducting bundle delivery experiments using a testbed.

Delay/disruption tolerant networking (DTN) was proposed for reliable data transfer despite frequent link disruptions and long propagation delay that are typical of the deep-space communication environment. DTN communications rely heavily on its core bundle protocol (BP) for reliable data delivery. To date, little work has been seen in theoretical analysis of the performance of BP in deep-space communications. In particular, an analytical understanding of the performance of BP for reliable data delivery in a deep-space communication environment in the presence of link disruptions is quickly needed. In this paper, we present a study of the effect of link disruption on transmission performance of BP, in both analytical and experimental manners, in a deep-space communications system characterized by link disruptions accompanied by an extremely long propagation delay and lossy data links. For the first time, an analytical framework is built to estimate the effect of link disruption on the total bundle delivery time of BP depending on its starting time with respect to bundle delivery. The analytical models are validated by running experiments using a test bed.

Bundle protocol (BP) is the main protocol of delay/disruption-tolerant networking which is developed to provide reliable data delivery services in a stressed communications environment. A typical application of BP is for data delivery in a challenging deep-space communication environment. However, little work has been done in analyzing the performance of BP in deep-space communications, especially in presence of highly channel-rate asymmetry. In this paper, we present analytical modeling of the transmission performance of BP over deep-space communication channels characterized by highly asymmetric channel rates. The model is built to estimate the expected file delivery time (and goodput) of the protocol for reliable data delivery in a deep-space transmission scenario. The model is validated by conducting data transfer experiments using a PC-based experimental test bed.