This paper addresses the communication modelling and synthesis problem for applications implemented on networks-on-chip. Due to the communication complexity of such systems it is difficult to estimate the communication delay. On the other hand, guaranteeing the timing constraints without detailed know-how about the communication is impossible. In this work we propose a communication modelling and synthesis approach for networks-on-chip where communication infrastructure is not able to provide communication interleaving (such as TDMA, virtual channels) or to guarantee communication delays. The idea is, to design a communication synthesis method, which would not be run off-chip as a CAD tool on a workstation, but on-chip and being activated whenever the system-on-chip (SoC) is re-configured.