Data transfer performance issues for a web services interface to synchrotron experiments

The Common Instrument Middleware Architecture (CIMA) defines a web services interface to scientific instruments. We have been experimenting with the use of CIMA web services for remote monitoring of synchrotron experiments and real-time data download, processing and storage. Here we discuss some performance issues with data transfer using CIMA web services, particularly for long-distance, high-latency transfers. We explore alternative approaches for improving the performance and robustness of data transfer with CIMA, and provide some experimental results