The thesis use algebra method, utilize options field in the IP message, with probability will through address of router to mark message, make by attack host can utilize mark message inside of address information reconstruct path, track to attack source.

Research and Implementation of Certification Path Construction Algorithm;

Even the topological simplification ofbridge CAs wasgiven,as cross certificate meshesgrow in size and complexity,the number of possible routes between points increases quickly,so that the time required for path discovery can increase beyond a tolerable delay for real-time operation.