Systematic Design Of SDN Northbound Interface For Telecommunications Network

SDN decouples the control and forwarding functions in the traditional network.With integrated network control,the SDN controller performs unified configuration management of the entire network through the southbound interface.In terms of business applications,it supports program ability of network applications through the northbound interface.These advantages of SDN technology provide a good way to replace traditional networks and provide a solution to the emerging telecommunications network service applications.SDN provides a programmable interface for application development through the northbound interface,enabling network service developers to implement not only traditional telecommunications applications but also innovative network applications.Because of the different manufacturers northbound interface implementations and complex network applications,industry currently does not have a unified northbound interface standard.Better design of the northbound interface is not only beneficial to SDN network technology itself,but also determines the future development of network applications.Through the research on the application and control function of SDN in telecommunications network,this thesis analyzes the business requirements of SDN controller northbound interface.Based on the abstraction level of the northward interface service function of the SDN controller,a northbound interface model based on the hierarchical architecture is designed.The northbound interface hierarchy model is divided into three levels: the basic level,the network level and the service level,through the upper layer calling lower layer API,to achieve a higher level of API.Using REST(Representational State Transfer,representational state transfer)related technology development,this thesis implements a function extensible SDN northbound interface;The SDN northbound interface with QoS(Quality of Service)parameters,including the acquisition of link network parameters,such as packet loss,delay,etc,are designed and implemented for telecommunications network service applications with high demand for quality of service such as streaming media,etc,but also on the user flow bandwidth management.And a service application service layer is designed based on the QoS northbound interface,so that the network administrator can obtain the service quality parameters in the network in real time and carry on the network control.The test results show that the hierarchical northbound interface designed in this thesis has someflexibility and extensible,which can provide some support for QoS service application of telecommunications network.