A Survivability Technique Of MPLS Networks Based On Braid Protection

The inevitability and huge damage of network failure make the research on networks survivability very necessary nowadays, especially when the transmission rate becomes higher in MPLS networks. Network survivability has become a key research issue for IP-based transport networks.Survivability is the capability of a network to maintain service continuity in the presence of faults within the network. The focus of this thesis is in MPLS network survivability.The features of MPLS network and the requirements of survival are fully considered and analyzed in this paper, an ultra fast segment shared protection scheme is then presented. Firstly, a new braid message through expanding the LDP messages was proposed. and according to this a novel braid protection path based on braid message is presented, which reduce the channel of reversed traffic flow and protect node and link failures at the same time. Secondly, a failure restoration mechanism based on braid protection path is presented, which make use of EXP bit in label and set buffers at every PML,recovery scheme start at the enter LSR of the failure segment, and the failure is recovered in the segment. The use of buffer avoids the packet loss and disorder and the use of segment idea reduces the recovery time. The experimental results show the scheme can relax recovery time, packet disorder, packet loss, and delay efficiently.MPLS network would be subjected to attacks, like camouflage, revise routing and so on. Failure restorations not only need to restore flow but also need to ensure the security of packets. To solve this problem, a fast heuristic algorithm to choose safety recovery path based on spare capacity allocation (SCA) is proposed, which called safety backup path (SBP) algorithm, the method considers the safety of every node as a factor of choosing the recovery path. The experimental results indicate the SBP algorithm can converges quickly and tranquilly, improves the security of the recovery path and allocates minimal amount of spare resources.