The Research & Design Of An Application-Oriented Border Routing Service Gateway

This thesis studies the issues related to access routing in multi-homed network environment using traditional network border gateway, the limitaions in BGP routing protocol and the deficiency of several networking traffic management algorithms. We combine application-layer protocol DNS and the third-layer routing protocol. Based on the interconnect topology information obtained from probing and abstraction, and the aggregated registered IP address information, we have designed an Application-Oriented Border Routing Service Gateway, providing optimal routing service for multi-homed network via border routing service gateway. In addition, our design requires no changes in ISP's backbone networks and routing prococols.Through careful analysis of the relationship between border gateway in multi-homed network and overall topology of the interconnected network, and the characteristics of IP addresses officially regisitered by access networks, we first propose the architecture design of BRSG border routing service gateway based on legacy border gateway technology in conjunction with application-layer DNS protocol. Our design concentrates on the components of the architecture, system data structure, working principle, processing workflow, and generation, query and maintenance strategy of routing table. We then study a number of related research works such as Quality of Service (QoS) , the topology discovery and automatic generation of the Internet, multi-cast routing, and DNS content-based routing. Based on these studies, we further propose a suite of routing algorithms suitable for Border Routing Service Gateway (BRSG) -- Application-Oriented Border Routing service gateway (AOBR). AOBR comprises address aggregation algorithm, topology abstraction algorithm, routing table generation algorithm and DNS customized service algorithm. Among these algorithms, address aggregation algorithm processes the officially registered IP addresses and aggregates the addresses in terms of service providers. Topology abstraction algorithm is responsible for the detection and abstract description of the Internet topology. Upon the completion of address aggregation and abstraction, routing generation algorithm constructs BRSG routing table. Finally, DNS customized service algorithm is the key to BRSG. It associates with system routing table, providing the resolved IP address of the best next link. Thus it implements the best routing access from exterior networks. While the routing access from interior to exterior networks is achieved directly through BRSG routing module.Compared with legacy routing algorithms, the proposed algorithm has newly added computation work mainly in the address aggregation and topology abstraction algorithm. Specifically, the processing of original registered address information in adderss aggregation...