Date Added: May 2011
In this paper analyzed WLAN - GPS -and synthetic traces that record mobility in a variety of network environments. The authors observe that from a macroscopic level, human mobility is symmetric. In other words, the number of users that move from point A to point B approximates the number of users that go in the opposite direction, i.e., from B to A. They show that this type of symmetry is more accentuated in synthetic mobility models, in particular, in random way-point mobility. They also study the direction of movement which also exhibits symmetric behavior in both real - as well as synthetic mobility. Additional contributions of their work include metrics to quantify mobility symmetry.