Research On Multipath Routing Technology And Corresponding Node Implementation

The Internet's original Internet routing protocols,such as OSPF and BGP,were designed primarily to provide end-to-end "best effort" services,which provided a single path to the destination subnet by leveraging distributed autonomous protocols.However,the exponential growth of Internet traffic and more and more extensive service scenarios make the upper layer of the application put forward new requirements on the lower layer of network link bandwidth,end-to-end delay,reliability and other indicators.In order to continue to provide services to the upper layer,operators constantly deploy new network equipment and lay higher speed of the underlying link.Traditional routing protocols are unable to make full use of the larger and larger network structure,and it is difficult to provide flexible transport services to the upper layer of the business.Multi-path transmission provides a new idea for the underlying network transmission,which makes full use of the spatial and temporal multiplexing capability on a single link,and can be used as a technical means to realize network functions such as bandwidth aggregation,minimizing end-to-end delay,improving robustness,increasing stability,load balancing,and secure decentralized routing.Because of the multi-network card interface of routing equipment and the multi-host deployment mode of the ISP of the autonomous system,the Internet topology naturally has the characteristic of multi-path,so it is feasible to realize multi-path transmission in the existing network.From a microscopic time perspective,the packets in the network are not evenly distributed,but have a sudden "train-like behavior",that is,the Flowlet phenomenon.This paper proposes a multi-path routing system with Flowlet as the transmission unit.The main work and contributions of this paper are as follows: First,the time difference between Flowlets is used to offset the delay difference between different paths during multi-path transmission,thereby solving the problem of out-of-order messages in multi-path transmission.Second,by embedding label information in the TTL field of IP packets,a multi-path routing system can be implemented in existing IP networks without affecting the original routing method.Third,the micro-flow label forwarding system is designed and implemented,using source routing,label forwarding,and triggering updates to solve the problems of routing control,clock synchronization,and distribution and update of control information in multi-path transmission.It is compatible with existing networks.Based on the protocol,a flexible multi-path routing system is realized.The test of the system verifies that the multi-path routing system has obvious advantages in improving network bandwidth,resisting link fluctuations,fault avoidance,and reducing message out-of-order rate.