Dome A, Antarctica, has been thought to be one of the best astronomical sites on the Earth for decades. Since it was first visited by astronomers in 2008, dozens of facilities for astronomical observation and site testing were deployed. Due to its special geographical location, the data and message exchange between Dome A and the domestic control center could only depend on Iridium. Because the link bandwidth of Iridium is extremely limited, the network traffic cost is quite expensive and the network is rather unstable, the commonly used data transfer tools, such as rsync and scp, are not suitable in this case. In this paper, we design and implement a data transfer tool called NBFTP (narrow bandwidth file transfer protocol) for the astronomical observation of Dome A. NBFTP uses a uniform interface to arrange all types of data and matches specific transmission schemes for different data types according to rules. Break-point resuming and extensibility functions are also implemented. Our experimental results show that NBFTP consumes 60% less network traffic than rsync when detecting the data pending to be transferred. When transferring small files of 1KB, the network traffic consumption of NBFTP is 40% less than rsync. However, as the file size increases, the network traffic consumption of NBFTP tends to approach rsync, but it is still smaller than rsync.

几十年来，南极洲的圆顶 A 一直被认为是地球上最好的天文地点之一。自 2008 年天文学家首次访问以来，已部署了数十个天文观测和现场测试设施。由于其特殊的地理位置，Dome A与国内控制中心之间的数据和消息交换只能依靠Iridium。由于Iridium的链路带宽极其有限，网络流量成本相当昂贵，网络不稳定，常用的数据传输工具，如rsync和scp不适合这种情况。在本文中，我们设计并实现了一个名为 NBFTP（窄带宽文件传输协议）的数据传输工具，用于 Dome A 的天文观测。NBFTP使用统一的接口来排列所有类型的数据，并根据规则为不同的数据类型匹配特定的传输方案。还实现了断点恢复和扩展功能。我们的实验结果表明，当检测到待传输的数据时，NBFTP 消耗的网络流量比 rsync 少 60%。在传输1KB的小文件时，NBFTP的网络流量消耗比rsync少40%。但是随着文件大小的增加，NBFTP的网络流量消耗趋于接近rsync，但还是比rsync小。我们的实验结果表明，当检测到待传输的数据时，NBFTP 消耗的网络流量比 rsync 少 60%。在传输1KB的小文件时，NBFTP的网络流量消耗比rsync少40%。但是随着文件大小的增加，NBFTP的网络流量消耗趋于接近rsync，但还是比rsync小。我们的实验结果表明，当检测到待传输的数据时，NBFTP 消耗的网络流量比 rsync 少 60%。在传输1KB的小文件时，NBFTP的网络流量消耗比rsync少40%。但是随着文件大小的增加，NBFTP的网络流量消耗趋于接近rsync，但还是比rsync小。