There are two general types of detection techniques: regularity-
based [4, 12] and shape-based [2, 1]. The regularity of traf-
c is described by second or higher-order statistics, such as
correlations in the data. Regularity tests include variance
testing and other statistical methods. The shape of trac is
described by rst-order statistics including mean, variance,
and distributions. Shape tests include the Kolmogorov-Smirnov
Test and entropy-based detection.