This paper presents the design, implementation, and evaluation of a class of packet-switching fabric architectures. Based on the well-investigated three-stage Clos-network, we propose a variety of packet-switches that are constructed by adding the most beneficial Network-on-Chip (NoC) paradigm which offers many distinct and practical advantages. Compared to the conventional crossbar switches, the NoC-based architectures provide better path-diversity, simple packet scheduling and speedup. A gradual design method is adopted to enhance the performance of the NoC switch, and several related issues such as the congestion avoidance, micro level load-balancing, and costeffectiveness are addressed. The NoC switches exhibit a high scalability potential in -both -the port count and traffic volume, making them a good candidate for the next-generation Data Center Networks.