航空固定电信网AFTN是中国民航重要的地空数据通信网络之一,它的建立、运行与安全涉及到航空运营部门的切身利益。虚拟专用网(VPN)是一种建立在公共网络上的专用网,具有建网方便快捷、节省资源、使用方便等特点。目前中国的电信运营商已经可以提供此业务。民航大量租用专线,运营成本较高,迫切需要一种可降低使用费用的网络。本文 AFTN is one of China’s civil aviation important air and ground data communication networks. Its establishment, operation and safety involve the vital interests of aviation operation departments. Virtual Private Network (VPN) is a private network built on the public network, with the characteristics of convenient and quick network construction, resource saving and easy to use. At present, China’s telecom operators can already provide this service. Civil Aviation leased a large number of green, high operating costs, the urgent need for a network that can reduce the cost of use. This article