JOINT ICTP/SISSA STATISTICAL PHYSICS SEMINAR Within the framework of a simple model, we are able to study the overall performance of a given informational network, depending on its uptaking as well as on the level of traffic control. Simple enough to get analytical results, it still shows a very rich phenomenology, presenting continuous, discontinuous as well as hybrid phase transitions between a free-flow phase and a congested phase, critical points and different scaling behaviors in the system size. We find that traffic control improves global performance, enlarging the free-flow region in parameter space only in heterogeneous networks. Traffic control introduces non-linear effects and, beyond a critical strength, may trigger the appearance of a congested phase in a discontinuous manner. The model also reproduces the cross-over in the scaling of traffic fluctuations empirically observed in the Internet. Ref: PRE 79, 015101(R) (2009) Jstat P08023 (2009)