  For the last few years, the amount of data has significantly increased in the
companies. It is the reason why data analysis methods have to evolve to meet
new demands. In this article, we introduce a practical analysis of a large
database from a telecommunication operator. The problem is to segment a
territory and characterize the retrieved areas owing to their inhabitant
behavior in terms of mobile telephony. We have call detail records collected
during five months in France. We propose a two stages analysis. The first one
aims at grouping source antennas which originating calls are similarly
distributed on target antennas and conversely for target antenna w.r.t. source
antenna. A geographic projection of the data is used to display the results on
a map of France. The second stage discretizes the time into periods between
which we note changes in distributions of calls emerging from the clusters of
source antennas. This enables an analysis of temporal changes of inhabitants
behavior in every area of the country.
