In System On Chip (SOC) with NOC interconnection paradigm, PIR (Packet Injection Rate) and routing algorithm are two critical factors that affect the efficiency of SOC communication. It’s observed that NOC may saturate at certain rate of injection packets. The effect of PIR on three routing algorithms in switch-based NOC with limited number of IP blocks is studied in this paper. The chosen algorithms for this work are fully adaptive, XY and west first; mesh topology is applied with 16 cores (NN style). Performance evaluation is conducted based on flit accurate and open source SystemC simulator.