The Setting And Research Of Cache Timer For Access Router Mapping Item

In traditional Internet protocol, IP address not only represents the location of a network node in the internet, but also represents the identity. The dual properties of IP address is the main cause of many problems such as routing scalability, security, mobility and so on. So how to separate the identity and locator and maintain the mapping relationship between the identity and locator to improve the routing scalability of Internet has become the hot issue researched at home and abroad.The work in this paper is based on the national "973" project, which is named with "The basic Theory of the Universal trustworthy Network", in order to improve the mapping performance of access switch router in Universal Network. First of all, the developing situation of separating identifier and.locator technology is summarized in this paper, and the architecture of Universal Network and the separation mapping mechanism of network layer under Universal Network are detailed introduced. Secondly, the outdated cases of mapping cache entries in access routers are researched by the further analysis of separation mapping mechanism. The mapping cache entry timer method on the access router is proposed to solve the packet loss problem caused by the outdated cache mapping entries. Thirdly, the functions of cache mapping entry timer method on access router are implemented by the programming of new data structure definition and function operation of cache mapping table. Finally, a reasonable value of timeout for the cache mapping timer is obtained though simulation. Besides, the test environment based on the prototype system is built, and the data packet loss problems caused by the outdated mapping cache entries under three different situations are analyzed. Theexperimental results show that, the packet loss problem caused by the outdated mapping cache entries could be solved effectively by the cache mapping mechanism and an appropriate value of timeout for the cache mapping timer.The cache mapping entry timer method on access router is obtained and implemented in this paper. The mechanism solves the data packet loss problems caused by the outdated mapping cache entries effectively, and improves the mapping performance of access router, which plays a significant role in identifier/locator separating and mapping mechanism for Universal Network.