Design And Implementation Of MPLS Failures Detection Mechanism And Protected Switching Mechanism

MPLS(Multi-Protocol Label Switched) is increasingly becoming the key technology in next generation backbone network, the backbone network of internet is the important resource which care about the national economy and the people's livelihood, the failures or the ruin of network structure more or less have a bad impact on the production and livelihood in sociaty, especially in unusually period or extremely evironment, such as war, natural calamities and so on. So, it is very important to improve the ability of self-healing and surviving of network, for this, OAM function should be add into the MPLS network. 0AM fuction is a important conception in modern administration of network, it can improve the reliability of network, make the operation simple, reduce the operating cost of network and guarantee the quality of service in network. The OAM mechanism in the MPLS network can guarantee the service operation nomally, so it is the hot research points all time in the world.This papar researched and analyzed recent technology, standards and criterions about MPLS OAM, especailly in fast failures detection mechanism and failures recovery mechanism, which are deeply researched in the paper, then we put forward two kinds method of failures detection mechanism in MPLS layer - the mechanism of LSP detection and the mechanism of bidirection FFD, and a method of failures detection mechanism in link layer - the mechanism of physical link monitoring; we also put forward a simple method of fast failures recovery - LSP Protected switching mechanism. Both of LSP detection mechanism and bidirection FFD mechanism are base on the module of MPLS OAM which we designed and realized by ourself, this module can use the OAM packets , which defined by ourself, to detect the link failures, and avoid the complex process in TCP/IP protocol stack, realize the cross-layer design, which can send the data packets to MPLS layer directly by MPLS socket interface. The mechanism of physical link monitoring can raise the alarm when the status of physical link change. In fast protected swithing mechanism, we modify the information of MPLS forwarding table by MPLS netlink interface, to realize swithing among LSPs. At last, we made some experiments to test and analyze the performance of these failure detection mechanism and failure recovery mechanism.