Bundle protocol (BP) was proposed as the core protocol of delay/disruption-tolerant networking for space. A hybrid reliable transmission mechanism based on integrating “proactive” retransmission and “reactive” retransmission of BP bundles has been presented as a means of achieving highly reliable file/data delivery in deep-space communications. Transmission overhead imposed by reliable delivery of data packets/bundles is consistently one of the key factors for efficient data delivery in space communications. It is especially important in deep-space networks, where the available electrical power on spacecraft for data delivery is a scarce resource but substantial energy is needed to propagate data over an extremely long deep-space channel. In this article, a detailed study of the transmission overhead for the hybrid retransmission approach of BP for reliable deep-space communications is presented. An analytical framework is presented for modeling the transmission overhead of BP as influenced by variations in channel quality, file size, bundle size, and retransmission timeout interval length. Its energy resource consumption is also briefly discussed. The analytical framework is validated by realistic file transfer experiments using a PC-based testbed infrastructure; the framework is found to be able to predict the performance with respect to the transmission overhead of BP.

中文翻译：

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深空通信混合束重传方法的传输开销研究

捆绑协议（BP）被提出作为空间延迟/中断容忍网络的核心协议。提出了一种基于 BP 包的“主动”重传和“反应”重传的混合可靠传输机制，作为在深空通信中实现高度可靠的文件/数据传输的一种手段。数据包/数据包的可靠传输所带来的传输开销始终是空间通信中高效数据传输的关键因素之一。这在深空网络中尤为重要，因为航天器上用于数据传输的可用电力是一种稀缺资源，但需要大量能量才能通过极长的深空通道传播数据。在本文中，详细研究了用于可靠深空通信的 BP 混合重传方法的传输开销。提出了一个分析框架，用于对受信道质量、文件大小、包大小和重传超时间隔长度变化影响的 BP 传输开销进行建模。还简要讨论了其能源资源消耗。分析框架通过使用基于 PC 的测试平台基础设施的实际文件传输实验进行验证；发现该框架能够预测 BP 传输开销的性能。和重传超时间隔长度。还简要讨论了其能源资源消耗。分析框架通过使用基于 PC 的测试平台基础设施的实际文件传输实验进行验证；发现该框架能够预测 BP 传输开销的性能。和重传超时间隔长度。还简要讨论了其能源资源消耗。分析框架通过使用基于 PC 的测试平台基础设施的实际文件传输实验进行验证；发现该框架能够预测 BP 传输开销的性能。