Load Balance In MPLS Networks

With the development of Internet, the applications over the Internet is becoming wider and wider. Providing QoS in Internet is becoming more and more important. Traffic Engineering is used to solve the problem of network insufficiency of available network resource that is caused by the development of network scale. However, traditional Traffic Engineering technology is limited by its inherent complexity to administrate and extend. It is exigent to seek a kind of new technology to overcome its limit. Traffic Engineering technology based on MPLS is the most promising technology that is commended by the industry.Load distribution across multiple parallel traffic trunks between two nodes is an important consideration. In many practical contexts, the aggregate traffic between two nodes may be such that no single link can carry the load. In an MPLS domain, this problem can be addressed by instantiating multiple traffic trunks between the two nodes, such that each traffic trunk carries a proportion of the aggregate traffic. Therefore, a flexible means of load assignment to multiple parallel traffic trunks carrying traffic between a pair of nodes is require.Firstly, we analyze the algorithms of load balancing. Dynamic multi-path load balancing algorithm is proposed---Flow-level multi-path load balance in MPLS network based on DT. This algorithm considers cross-traffic in real networks, which core LSRs are not required to perform traffic engineering and ingress LSRs record flow-state and LSP-state. We use probing packets to obtain delay and drop rate of multiple LSPs. We minimized an effective cost function, then compute the DT and distribute traffic among the LSPs. Moreover, we categorize data packets at the flow level, and it decreases packet disorder. Simulation results show that our approach improves the throughput, reduces the end-to-end delay and the packet drop rate.