  In the current intensively changing technological environment, wireless
network operators try to manage the increase of global traffic, optimizing the
use of the available resources. This involves associating each user to one of
its reachable wireless networks; a decision that can be made on the user side,
in which case inefficiencies stem from user selfishness.
  This paper aims at correcting that efficiency loss through the use of a
one-dimensional incentive signal, interpreted as a price. While the so-called
Pigovian taxes allow to deal with homogeneous users, we consider here two
classes with different sensitivities to the Quality of Service, reflecting the
dichotomy between delay-sensitive and delay-insensitive applications. We
consider a geographic area covered by two wireless networks, among which users
choose based on a trade-off between the quality of service and the price to
pay.
  Using a non-atomic routing game model, we study analytically the case of
constant demand levels. We show that when properly designed, the incentives
elicit efficient user-network associations. Moreover, those optimal incentives
can be simply computed by the wireless operator, using only some information
that is easily available. Finally, the performance of the incentive scheme
under dynamic demand (users opening and closing connections over time) are
investigated through simulations, our incentive scheme also yielding
significant improvements in that case.
