The Technology And Implementation Of OSPF Protocol Based On IPv6

In the last ten years, Internet has gained tremendous success and affected people's life deeply. However, with great scaling, the current Internet Protocol has revealed many inherent flaws. IPv6 is the abbreviation of "Internet Protocol Version 6(IPv6)". It is the next generation of Internet Protocol designed by IETF(Internet Engineering Task Force), and designed to replace "Internet Protocol version 4( IPv4 ) ". It can solve the problems faced by the current IP with more flexibility and efficiency. OSPF( Open Shortest Path First ) is classified as an IGP, which are used within autonomous systems. OSPF is a routing protocol based on link state algorithm. It was designed to overcome some of the limitations introduced by RIP, such as the small diameter, long convergence time, and a metric that does not reflect the characteristics of the network. In addition, OSPF handles a much larger routingtable to accommodate large number of routes. OSPF was firstly issued in RFC1247 by lETF. After being modified repeatedly, the Version 2 0SPF is published in RFC2328. However,along with the transition from IPv4 to IPv6, some changes of OSPFv2 have been necessary for supporting the exchange of routing information based on IPv6. The Version 3 0SPF based on IPv6 is published in RFC2740. And some draft of OSPFv3 has been working in progress. This paper has detailedly discussed the technology and implementation of OSPFv3. At first, thesis give an introduction of the basic concept of OSPF protocol, including the definition of area types, router types, network types. Then it briefly analyses the procedure of routing based on IPv6 and the differences between OSPFv3 and OSPFv2, and detailedly introduces the specification of OSPFv3 protocol, including data structure and OSPF package format. At last, we give out the key details of implementation, and at the same time discuss some crucial data structure, process flowing, etc.. While the Link State Update Packets of AS (Autonomy System) external routing area broadcast to internal routers, they use much router memory and data link bandwidth. We present a better flooding algorithm, which can reduce the memory and data link bandwidth needed,and describe a mechanism for supporting multiple address families in OSPFv3.