Because SSH traditionally has been more focused on providing security, it does not always provide peak network performance. So members of the PSC network group created a software patch to overcome this bottleneck. In many circumstances, this patch, called HPN-SSH, can give more than a 10-fold speed-up in performance.

HPN-SSH implements run-time buffer sizing to eliminate flow control buffer bottlenecks for scp/sftp transfers on high-latency bandwidth links. They also add the option to disable encryption of scp transfers for improved performance.

The inclusion of the HPN-SSH functionality in GSI-SSH had been requested by both the NEESit and Virtual Data Toolkit teams. GSI-OpenSSH will be available in the next release of the Globus Toolkit and will be available on TeraGrid systems this spring.

"This is a nice example of NCSA and PSC working together to deliver useful cyberinfrastructure to scientific communities", stated NCSA senior research scientist Jim Basney.

"Working with NCSA and OpenSSH has been a great experience", stated PSC network engineer Chris Rapier. "Together we've been able to give users an easy-to-use and secure tool for rapidly transferring large amounts of data over the TeraGrid network." Cisco Systems Inc. supported PSC's work on HPN-SSH.