GridFTP, designed by using the Globus XIO framework, is one of the most popular methods for performing data transfers in the Grid environment. But the performance of GridFTP in WAN is limited by the relatively low communication bandwidth offered by existing network protocols. On the other hand, modern interconnects such as InfiniBand, with many advanced communication features such as zerocopy protocol and RDMA operations, can greatly improve communication efficiency. In this paper, we take on the challenge of combining the ease of use of the Globus XIO framework and the high performance achieved through InfiniBand communication, thereby natively supporting GridFTP over InfiniBand-based networks. The Advanced Data Transfer Service (ADTS), designed in our previous work, provides the low-level InfiniBand support to the Globus XIO layer. We introduce the concepts of I/O staging in the Globus XIO ADTS driver to achieve efficient diskbased data transfers. We evaluate our designs in both LAN...