From the Kepler mission four planets were detected and confirmed in the Kepler-82 system. The two inner ones (d and e) show no transit timing variations (TTVs) and are dynamically independent from the two outer ones (b and c), which are showing TTVs. A dynamical analysis of the Kepler-82b/c system delivered a very high, hardly to explain, density ratio of about ten between the planets. A chopping component in the TTVs of the outer planet (Kepler-82b) is not explained by the two-planet model. This chopping component hints on another outer planet near the 3:2 or 3:1 resonance to planet c. The time span of Kepler observations are too short for distinguishing between the two models, the dynamical cycle is not fully covered. The completion of the dynamical cycle of this and other Kepler Objects of Interest (KOIs) showing TTVs is the aim of the KOINet. Within the network follow-up observations with ground-based telescopes are organized. These follow-up observations of Kepler-82b/c transits helped to distinguish between the two models, resulting is the detection of a new planet near the 3:2 resonance to Kepler-82d in the system. A detailed photodynamical modelling of the system was carried out to fully characterise the system parameters. The inclusion of the new planet also lead to a more reasonable density ratio of planet b to c of about two.