Study And Implement Of A Kind Of BGP Multi-Path Expansion Mechanism

With the explosive growth of Internet, it has long been recognized that the current inter-domain routing protocol (BGP) does not always satisfy the diverse performance, reliability, and security requirements of end users and applications. The demand of improving BGP protocol is becoming more and more pressing. The difficulty of achieving the transition about routing protocol in the internet in which such a large-scale and geographical distribution and ownership are not unified makes us resolve the existing problems gradually only in a kind of way which will not affect the day-to-day running of BGP protocol and enhance BGP protocol to meet the new demand only by introducing new features.The work in this paper relies on the project of Universal trustworthy Network and pervasive Services, which is in National Basic Research Program (973 Program). BGP Multi-Path Expansion Mechanism is a kind of optional inter-domain routing protocol solutions, which separates the support to multi-path inter-domain routing by introducing AS-level path selection, IP-in-IP tunnel encapsulation technology and Multi-Path Expansion Mechanism routing negotiation strategy on the basis of maintaining compatibility of BGP protocol. Routing negotiation strategy is a pivotal portion of BGP Multi-Path Expansion Mechanism, which helps the research and development on BGP Multi-Path Expansion Mechanism.This paper mainly addresses the problem that how to design and implement BGP Multi-Path Expansion Mechanism which is a kind of optional inter-domain routing protocol solutions. Firstly, we briefly introduce some typical solution of multi-path routing in internet, analyze their advantages and disadvantages, and make a brief comparison. Secondly, we introduce the basic routing protocol stack of BGP, analyze the function requirements on Routing negotiation strategy, and propose the solution about how to realize AS-level path selection and Multi-Path Negotiating as well as the implementation of the protocol stack. Thirdly, we implement and test the function of BGP Multi-Path Expansion Mechanism in Linux.We test and analyze the program in our prototype. The experiment results show that the protocol stack meets the demand of the Multi-Path inter-domain routing, makes compatible with BGP protocol well, provides optional alternate routes according to user's requirements, and configure more flexible routing policies. With realizing the expansion mechanism,the negotiation on alternate routes between ASes also introduces a large number of significant issues which represents an important step towards the eventual development and adoption of a practical multi-path expansion mechanism.