Before revision:  This reveals that the  backoff process is heavy-tailed in the strict sense for m^2 \gamma>1 , essentially due to collision. Moreover, we identify long-range dependence in 802.11 through both of mathematical and empirical wavelet-based analyses and answer a riddle: the absence of long range dependence in aggregate total load.
After revision:  This reveals that the backoff process is heavy-tailed in the strict sense for m^2 \gamma>1 /m^2, and paves the way for the following unifying result. The state-of-the-art theory on the superposition of the heavy-tailed processes is applied to establish a dichotomy exhibited by the aggregate backoff process, putting emphasis on the importance of time-scale on which we view the backoff processes. While the aggregation on normal time-scales leads to a Poisson process, it is approximated by a new limiting process possessing long-range dependence in 802.11 through both of mathematical and empirical wavelet-based analyses and answer a riddle: the absence of long range dependence in aggregate total load.