Fast Reroute And Its Mechanism Realization Based On MPLS Traffic Engineering

Multi-Protocol Label Switching,which is a typical integrated model technique supporting IP over ATM, simplifies the packet transmitting and integrates L2 switching with L3 routing. So it can support explicit routing and achieve Internet traffic engineering (TE) and VPN effectively. Traffic engineering is a technology to make full use of the network resources. It can be used to make the network resources uniform, which can avoid network congestion, by arranging the data traffic through IP networks reasonably.FRR mechanism is an extension of MPLS TE. FRR can switch the traffic load immediately to the backup path when a node or link in the LSP fails, and then improve the performance of network. The backup LSP tunnels for local repair are needed to be pre-established. And then FRR enable the re-direction of traffic onto backup LSP tunnels in 10s of milliseconds, in the event of a node or link in the LSP fails. It is extremely important that the flow of labeled traffic will be not disrupted due to the immediate switchover.This paper introduces the MPLS TE technology as well as signal protocol RSVP-TE to implement the MPLS TE in detail, and then introduces principles and functionalities of FRR facility, which are mechanisms of RSVP-TE extensions. MPLS TE FRR facility is implemented using ANSI C, and are tested in a real experimental network. The test result indicated that the realization of FRR mechanism can switch with minimal increase in latency, and reduce packet loss when links or nodes are invalid. So it does have a great improvement in the performance of network.