软件定义传送网(SDTN)通过将控制功能与传送功能分离，对传送网的网络资源和状态进行逻辑集中控制，实现传送网络的可编程性和自动化控制，构建面向业务应用的灵活、开放和智能的传送网络体系架构。在SDTN体系架构中，北向接口是连接SDTN控制器与上层应用的重要纽带，但目前仍没有统一的标准，给SDTN的发展带来了困难。文章对当前热门的北向接口信息模型传输应用编程接口(TAPI)进行了探讨，结合SDTN协同控制器设计实现了TAPI北向接口，并测试验证了TAPI北向接口信息模型的有效性和互操作性，为SDTN北向接口信息模型的选用提供了参考。

Software Defined Transport Network (SDTN) controls the network resources and status of the transport network logically and centrally by separating control function and transmission function, which can realize the programmability and automatic control of transport network. It can also build a flexible, open, and intelligent transport network architecture for business applications. In the software-defined transport network architecture, the northbound interface is an important link between the SDTN controller and the upper application. However, there is no unified standard, which has brought difficulties to the development of the SDTN. This paper first discusses the popular northbound interface information model Transport Application Programming Interface (TAPI). Then we design and implement the TAPI northbound interface in combination with the SDTN coordinate controller to test and verify the effectiveness and interoperability of the TAPI northbound interface information model. Finally, we provide a reference for the selection of the SDTN northbound interface information model.