Research And Implementation Of Label Link Detection System Based On IP RAN

With the rapid expansion of network services,many technologies used by operators previously have been unable to meet the emerging fast and changeable requirements.For example,frame relay(FR)and ATM technologies,such technology is not only expensive but also unable to meet the explosive demand of data service.Multi protocol label switching(MPLS)technology supports multiple labels,which is very suitable for multi-service bearer channel;the technology of transport network has a strong business carrying capacity and flexible data forwarding capabilities.The combination of the MPLS and transport network is an excellent solution of the deployment of efficient data service bearer network.In the increasingly widespread application of MPLS technology networking,how to detect the connectivity of label links effectively and locate the fault points quickly is an important issue to ensure reliable operation of network.Although bidirectional forwarding detection(BFD)can detect link connectivity effectively,the connectivity of signaling channel between control plane and forwarding plane is not detectable for high-end routers,and it is unable to locate which node of the network is malfunctioning.Based on the idea of IP ping / trace route,this paper proposes an effective detection method,which has been applied and implemented to the environment of label networking.The main content of the thesis includes:(1)The label link detection system.In the control plane,to achieve the command line detection,and the OAM protocol module implements the initial package of the message.In the forwarding plane,encapsulating request message label and sending up the original packet of the reply.(2)Key points of link detection system.As the design requires that the protocol module encapsulates the detection packets to the IP layer,so it is required to create an OAM interface for tag detection in the protocol stack of the router,which is used to distinguish the signaling channel from the protocol module to the protocol stack.(3)In the high-level router of which the forwarding plane and the control plane is separated,a packet encapsulation format for communication of boards is designed to transmit the link information between the control plane and the forwarding plane.(4)Three kinds of detection message forwarding is implemented by encoding the microcode of C3 network processor.