> By Assia Hamzaoui and Matthieu Latapy
In the same spirit as in the plot named Dynamics of IP addresses around me, we use egocentric measurements of the Internet. We seek to observe and understand the dynamics of the IP internet topology by detecting events in it.
A natural way to see events would be to observe the number of IP addresses seen at each round, as shown on the red curve of the plot. Events appear in such plots as downward peaks. This tells us little about the causes of the event. Mainly these peaks indicate loss of connectivity around the monitor, which is not a very important information. One may notice that no significant upward peak appears in this curve. This does not mean that such peaks are not possible.
On the contrary, the blue curve of the plot, which presents the number of distinct IP addresses seen during ten consecutive rounds, seems to show more information. Here one can see upward peaks that indicate remarkable changes in the IP addresses observed in the corresponding ten rounds, thus important routing changes. One can ask the question whether the set of IP adresses that constitute a peak corresponds to a specific part of the network, and thus confirms the occurrence of a significant event.
More details in this paper.