Thermal issues are an increasing concern in microelectronics due to increased power density as well as the increasing vulnerability of the system to temperature effects (delay, leakage, reliability). NoCs promise to relieve many of the scaling problems that arise with increasing levels of on-chip system integration. However, as the technology scales, temperature effects become more significant and designing for performance becomes more difficult. It is crucial for designers to understand the impact of thermal variations on these systems to reduce hotspots and maintain performance.