Design And Implementation Of OSPFv3 Protocol In The High-Performance IPv6 Router

With the large-scale deployment of hardware forwarding engine in High-end IP routers, the legacy routing software architectures based on real-time, monolithic code bases are ill-equipped to support rapid development of features and stable operation that are required in the Internet core. High-Performance IPv6 Router adopt the architecture of integrated processing and distributed forwarding in which data IP packets are mostly forwarded by hardware forwarding engine. Without the contention of CPU between forwarding data packets and routing software, it permits the routing software to execute in a general-purpose operating system environment that provides greater reliability and scalability.This thesis is one of the achievements of "The Base Platform and Experimental System of High performance IPv6 Router", which is one of the key projects announced by HIGH-TECH RESEARCH AND DEVELOPMENT'S PROGRAMME OF CHINA in the tenth five-year plan, it deeply researches into the implementation techniques of OSPFv3 protocol. In this thesis, we first demonstrate that the legacy non-structural monolithic routing software is not fit for the implementation scheme of the routing software in High Performance IPv6 Router, then we make a deep analysis on the three modular routing software implementations based on which we propose a routing software implementation technology ED-VMT that is appropriate for complex protocol moduling.In the second part of this thesis, we design and implement the key modules of OSPFv3 protocol by using ED-VMT technology and optimize the SPF calculation process. The main contribution of this thesis is as follows: Propose a kind of routing software implementation technology ED-VMT that fit for complex protocol moduling.Based on thorough analysis of the three routing software packets MRT, GateD and GNU Zebra nearly 40000 source codes and combined with the demand on routing software of High Performance IPv6 Router and OSPFv3 protocol implementation characteristics, we propose Event Derived Virtual Multi-Task routing software implementation technology, design the architecture of the routing software based on ED-VMT and the key techniques in ED-VMT; Design and implement the key modules in OSPFv3 protocol software by using ED-VMT technology. Based on the analysis of OSPFv3 protocol, we design the framework of our OSPFv3 protocol software, and then give the dataflow of our OSPFv3 protocol software. At last, we design and implement the following modules of OSPFv3 protocol software:Protocol packet processing module, Link state database module, Flooding protocol module , Route processing module; Optimize the SPF calculation which is the core function of OSPFv3 protocol software. Our main work centralizes on the optimization of Dijkstra algorithm. By the using of binary heap in constructing candidate list during the SPF calculation and through the modification on the SPF calculation itself, we achieve a SPF calculation average time complexity of O((N+M)logN).