Energy Consumption of Bundle Protocol for Reliable File Delivery over Deep-Space Channels

Delay-/disruption-tolerant networking (DTN) is developed for reliable data delivery in challenging communication environments such as the harsh deep-space environment where the traditional Internet protocols (mainly TCP/IP) typically do not work effectively. Because the energy resources available on space spacecrafts are generally very limited, energy consumption is an important performance issue for space communications. Energy resource consumption is even critical for communication systems in deep-space flight missions, and it must be evaluated with respect to the transmission efficiency. Bundle protocol (BP) was developed as the main protocol of DTN for reliable data transmission. Some studies have been done in evaluating the transmission performance, mainly throughput/goodput, on the use of the "reliable BP" for file delivery in deep-space communication scenarios. However, a very limited number of studies have been done in investigating the energy resource consumption issue of BP. In this paper, analytical modeling and the numerical evaluation results are presented to study this issue. The analysis is done by considering both the traditional "reactive" retransmission method and "proactive" retransmission method for reliable transmission service of BP. It is found that the "proactive" retransmission method of BP transmits a much larger amount of data than the traditional transmission method for reliable delivery of a file, leading to extra energy consumption.