Astronomers benefit from NEXPReS and GÉANT
Cambridge, UK | 30 October 2013
NEXPReS project improves radio astronomy techniques with GÉANT
After three years, the ground-breaking NEXPReS project finished in July this year. NEXPReS (Novel EXplorations Pushing Robust e-VLBI Services) has successfully helped the radio astronomy community and been at the forefront of trialling new advances in research networking technology, particularly in areas such as Bandwidth on Demand (BoD).
Begun in 2010, NEXPReS aimed to improve astronomical techniques by eliminating the distinction between traditional disk-based Very Long Baseline Interferometry (VLBI) and real-time electronic VLBI (e-VLBI) techniques.
VLBI uses multiple radio telescopes distributed across great distances to observe the same region of sky simultaneously. Data from each telescope is recorded on hard disks and then sent to a central supercomputer to correlate results to produce high resolution images.
e-VLBI replaces disks by streaming data across research networks to the same central correlator, delivering faster results and enabling real time observations of short-lived astronomical phenomena. However e-VLBI doesn’t allow for data to be re-correlated and relies on constant network connections.
Through new data caching, network storage, cloud correlation and bandwidth on demand techniques, NEXPReS's goal was to bring together the reliability and robustness of VLBI with the speed and flexibility of e-VLBI for every observation conducted by the European VLBI Network (EVN). Funded by the European Union under the Seventh Framework Programme (RI-261525), NEXPReS was made up of 15 partner institutes in eleven countries, coordinated by the Joint Institute for VLBI in Europe (JIVE). Networking partners in the project included DANTE, NORDUnet, PSNC and SURFnet.
Research networks such as GÉANT and its NREN partners have been a key part of the project's success. e-VLBI simply cannot be carried out without the power of research networks, as it relies on high speed, reliable connections between telescopes around Europe (and beyond) and JIVE in the Netherlands. As T. Charles Yun, NEXPReS project manager points out, long term collaboration has been vital, "It is important that R&E networks have cooperated with radio astronomy over long periods so that we can learn what technologies are coming and influence future work and participate in its development."
First use of NSI protocol
NEXPReS has been a pioneer in using Bandwidth on Demand (BoD) and was the first project to use the new Network Services Infrastructure (NSI) protocol. NSI provides a standardised interface, allowing users to quickly and easily create interoperable BoD services across multiple research networks.
Pathfinder for the Square Kilometre Array
Looking further ahead, the lessons learned from NEXPReS will inform the planned Square Kilometre Array (SKA), the world's largest and most sensitive radio telescope. Made up of thousands of linked radio wave receptors located in Australia and in Southern Africa, the SKA will create a telescope with a collecting area equivalent to a dish with an area of about one square kilometre and will generate enormous amounts of data to be analysed and shared amongst the global astronomy community. The work of NEXPReS will act as a pathfinder project for many areas of SKA, including distributed storage and bandwidth on demand.
Through close collaboration with research networks and astronomers NEXPReS has succeeded in providing the best of both worlds – the immediacy of e-VLBI and the stability of recorded VLBI, improving our ability to study the universe around us.
Re-published from CONNECT Issue 12.
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