Radio Astronomy data transfer using KAREN network

The Kiwi Advanced Research and Education Network (KAREN) has been used to transfer large volumes of radio astronomical data between the Radio Astronomical Observatory at Warkworth, New Zealand and various international organizations involved in joint projects and VLBI observations. Here we report on the current status of connectivity and on the results of testing different data transfer protocols. We investigate new UDP protocols such as `tsunami´ and UDT and demonstrate that the UDT protocol is more efficient than `tsunami´ and `ftp´. We also report on tests of direct data streaming from the radio telescope receiving system to a correlation centre without intermediate buffering or recording (real-time eVLBI).