Research On Data-Link Layer Extension To IP Trackback

With the development of network technology and application, network security becomes more and more important. Denial of service attack is among the hardest security Problems to address because it is easy to launch, difficult to defend and trace. So, doing research on DoS attack and its countermeasures is not only challenging but also very important. And IP Traceback is the key thesis in the research.In this thesis, the mechanism, methods of and countermeasures to denial of services attacks are discussed. Several IP Traceback schemes, especially the Packet Marking schemes are reviewed and some improvements to the current Packet marking schemes are given. Based on the research on schemes of Data-Link Layer extension to IP trackback, a Data-Link Layer extension to IP Packet Marking schemes is proposed, it can identify attackers on Data-Link Layer after trace the leaf router.For achieve high security and robustness, a new frame tag is provided. The tagging algorithm to frame has no affection to existing Ethernet networks. The data-storage structure for the schemes is improved.Experiments show the new scheme has good effect to traceback on Data-Link Layer, and the improvement to it is successful.