Abstract: The Internet topology, especially the AS-level topology, is the hotspot issue of the research. We can comprebend well the inner connective mechanism of the network by researching the evolvement trend of the Internet topology.In this thesis, the research task is based on the massive data authorized by CAIDA(The Cooperative Association for Internet Data Analysis) Skitter project and the data's time span is from January 2004 to June 2008. This paper introduced the essential basic conceptions first,then carried out the CCDF(d)-degree power-law analysis, the degrecrank analysis and the node aging analysis. It is shown by the evolvement of the network topology structure that the top degree nodes of the AS-level Internet are stable and maintenance the clustering and the power-law of network. But these nodes lost the efficiency connection gradually by time and the network topology presents the trend of the laggard evenly.

Key words: AS-level, Internet topology, Power-law, Node aging