A Note on Power-Laws of Internet Topology

The three Power-Laws proposed by Faloutsos et al. (1999) are important discoveries among many recent works on finding hidden rules in the seemingly chaotic Internet topology. In this note, we want to point out that the first two laws discovered by Faloutsos et al. (1999, hereafter, Faloutsos’ Power Laws) are in fact equivalent. That is, as long as any one of them is true, the other can be derived from it, and vice versa. Although these two laws are equivalent, they provide different ways to measure the exponents of their corresponding power law relations. We also show that these two measures will give equivalent results, but with different error bars. We argue that for nodes of not very large out-degree(≤ 32 in our simulation), the first Faloutsos’ Power Law is superior to the second one in giving a better estimate of the exponent, while for nodes of very large out-degree(> 32) the power law relation may not be present, at least for the relation between the frequency of out-degree and node out-degree.