We introduce a novel heterogeneous NoC router architecture, supporting different link bandwidths and different number of virtual channels (VCs) per unidirectional port. The NoC router is based on shared-buffer architecture and has the advantages of ingress and egress bandwidth decoupling, and better performance as compared with input-buffer router architecture. We present the challenges facing the design of such heterogeneous NoC router, and describe how this router architecture addresses them. We introduce and formally prove a novel approach that reduces the number of required middle shared-buffers without affecting the performance of the router. In comparison with an optimal input-buffer homogeneous router, our NoC router improves saturation throughput by 6-47 percent for standard traffic patterns. The router achieves significant run-time improvement for NoC-based CMP running PARSEC benchmarks. It offers better scalability, area, and power reduction of 15-60 percent, for NoC based CMPs of size 4 × 4 up to 16 × 16, as compared with optimal input-buffer homogeneous and heterogeneous routers.