Data center networking brought a new era of data-intensive applications such as remote direct memory access, high-performance computing, and cloud computing, which raise new challenges for network researchers. Such applications require minimum network latency, no packet loss, and fairness between flows. Therefore, IEEE Data Center Bridging Task Group presents several enhancements for Ethernet networks to fulfill these requirements. In this context, we investigate the possibility of achieving dropless Ethernet. We extend our previously proposed congestion control protocol, named Heterogeneous Flow (HetFlow), to achieve minimum queue length and consequently minimum network latency. In addition, we present a mathematical model, stability analysis, and scalability study of the proposed protocol. Further, extensive simulation experiments are conducted to verify our mathematical analysis. Moreover, it is illustrated by simulations that HetFlow improves fairness between flows of different packet sizes and different round trip times.