Modern data centers accommodate tens or even hundreds of thousands of servers. The sheer volume of servers in these data centers greatly increases the requirements of the supporting network with regards to scalable bisection bandwidth, network latency, fault-tolerance, manageability, and network cost. Traditional Ethernet, which inherits several characteristics from the shared media service model, has a hard time satisfying all of these demands. In this paper, Eth Speeder, a high performance fault-tolerant and scalable layer 2 Ethernet network architecture, is proposed as a possible solution for large-scale data center environments. To evaluate the effectiveness of Eth Speeder, the ES 64, a 64-gigabit-port cut-through switch based on the Eth Speeder protocol, was designed and implemented using FPGA technology. Compared with leading commodity Ethernet switches, the ES 64 with 700 ns switching latency can offer up to 79% improvement in all-to-all bandwidth and up to 70% performance improvement of real applications.