  We show that the load at each node in a preferential attachment network
scales as a power of the degree of the node. For a network whose degree
distribution is p(k) ~ k^(-gamma), we show that the load is l(k) ~ k^eta with
eta = gamma - 1, implying that the probability distribution for the load is
p(l) ~ 1/l^2 independent of gamma. The results are obtained through scaling
arguments supported by finite size scaling studies. They contradict earlier
claims, but are in agreement with the exact solution for the special case of
tree graphs. Results are also presented for real communications networks at the
IP layer, using the latest available data. Our analysis of the data shows
relatively poor power-law degree distributions as compared to the scaling of
the load versus degree. This emphasizes the importance of the load in network
analysis.
