The introduction of software defined networking (SDN) has created an opportunity for file access services
to get a view of the underlying network and to further optimize large data transfers. This opportunity
is still unexplored while the amount of data that needs to be transferred is growing. Data transfers are
also becoming more frequent as a result of interdisciplinary collaborations and the nature of research
infrastructures. To address the needs for larger and more frequent data transfers, we propose an approach
which enables file access services to use SDN. We extend the file access services developed in our earlier
work by including network resources in the provisioning for large data transfers. A novel SDN-aware file
transfer mechanism is prototyped for improving the performance and reliability of large data transfers
on research infrastructure equipped with programmable network switches. Our results show that I/O
and data-intensive scientific workflows benefit from SDN-aware file access services