We couldn't do research this way without SWITCHlan.

SWITCH's high-speed network plays a key role for international research in Switzerland. Here are two examples.

Text: Anja Eigenmann, published on 15.11.2016

More and more public and private research teams are using SWITCHlan. Some have already been using it for many years. Among them are the Swiss research teams that supplied data to the global project resulting in the 2013 Nobel Prize in Physics. SWITCHlan also helps to produce detailed weather forecasts every day, contributing to the safety of the Swiss population.

Nobel prizewinning particle physics

4 July 2012: CERN finds the Higgs boson. This represents a milestone in particle physics as it is the first experimental proof that the particle first predicted back in the 1960s actually exists. A year later, in 2013, researchers François Englert and Peter Higgs are awarded the Nobel Prize for providing the theoretical basis for this fast-decaying particle.

Something the general public is unaware of is that several Swiss research groups were instrumental in proving the existence of the Higgs boson, and all of them rely on SWITCHlan to transfer data. They analyse data produced in CERN's particle accelerator, the Large Hadron Collider (LHC).

The network has become a crucial element in our experiments. We couldn't do research they way we do without SWITCHlan.

Christoph Grab, particle physicist

Christoph Grab coordinates the national computing resources used by the Swiss groups, which cooperate with others around the world on the three LHC experiments, Compact Muon Solenoid (CMS), ATLAS and LHCb. "The network has become a crucial element in our experiments. We couldn't do research they way we do without SWITCHlan", explains Grab. To understand why, it is important to know how particle physics research is organised these days.

The particle accelerator at CERN produces vast quantities of data by colliding protons or atomic nuclei. These quantities are so vast, in fact, that they cannot simply be saved to disk. The CMS experiment, for instance, produces up to 4.5 petabytes of data per second. By way of comparison, Google processes roughly 20 petabytes of data per day, i.e. 19,440 times less. Special algorithms are used to reduce the volume of the CMS data by a factor of approximately one million. This makes it possible to process them and save them to disk at CERN. They are then sent via a dedicated network to about a dozen major computing centres around the globe, where additional reconstruction algorithms are used. Large quantities of these data are then distributed to more than 60 countries worldwide. Researchers access them, carry out their calculations and interpret the results. However, these calculations still require massive amounts of computing power, so the physicists work with distributed capacity spread across more than 150 computing centres all over the world.

To date, over 300 petabytes of data have been stored on disks globally for the experiments, and 50 gigabytes are sent across the world's networks every second on average. A 90-minute feature film takes up roughly 10 GB, so this equates to five films per second. The data produced by the Swiss teams working on the LHC experiments are stored on a server at the National Supercomputing Center or Centro Svizzero di Calcolo Scientifico (CSCS) in Lugano, with daily traffic reaching some 60 terabytes.

"We're very pleased with SWITCHlan. No one else can offer us the stability and the bandwidths we need," notes Grab. "Thanks to the redundancy, problems have been very rare – even more so since the third link was built. The worst we've experienced has been the occasional slight delay. Our work isn't a matter of life and death, so it's not so bad for us if we have to wait an extra half an hour for results once in a while. We also know that we can increase capacity to 100 Gbit/s if we need to."

There have been some security incidents. "But they were always dealt with very quickly and professionally," recalls Grab. "SWITCH-CERT communicates them, and the administrators fix them straight away. They know exactly what to do. We've never sustained any major damage."


Weather forecasts to keep the population safe

Weather forecasts have become increasingly detailed over the years. The Federal Office of Meteorology and Climatology (MeteoSwiss) is currently installing a new and even more precise forecasting model called COSMO-NExT. Together with the CSCSMeteoSwiss won the Swiss ICT Award 2016 for the new forecasting model on 15 November. COSMO-NExT reduces the grid box size, i.e. the distance between topographical data points, from two kilometres to just one. However, this increased resolution also means an increase in data volumes. The data are handled by graphics processors that are 40 times faster than normal CPUs. This is a world first for a national weather service. The computers are located at the CSCS in Lugano and connected – like the Internet – via SWITCHlan.

"The availability and performance of SWITCHlan are vital for us. We need to be able to send large volumes of data to our supercomputer in Lugano reliably," explains Martin Schäfer, Head of Information and Communication Technology at MeteoSwiss. "Availability is essential, especially for flight weather around the airport in Kloten. Some of the data we rely on is sent via the Internet. Being able to react quickly and send out warnings is particularly important in cases of ice, storms and lightning, when the weather situation changes rapidly, so we need a fast and reliable way to receive the relevant information," says Schäfer.

In general, our experience with SWITCH is very positive. We value the personal contact we have with the experts

Martin Schäfer, Head of Information and Communication Technology MeteoSwiss

MeteoSwiss is tasked with warning the population about extreme weather. Every single person living in Switzerland thus benefits from detailed weather forecasts that can also be consulted on the move through a smartphone app – when a storm is moving in, for example, or when someone is planning a hike in the mountains. At the same time, reliable weather simulations are also needed for statistically improbable events such nuclear accidents.

The weather: a time-lapse edit of images from the SWITCH camera on the Jungfraujoch. (Video editing by Dominik Aebli)

MeteoSwiss has another important remit in terms of research in the fields of climatology and meteorology. Direct access to the academic network is therefore an additional advantage that SWITCHlan offers with regard to collaborating with the universities. Since weather and climate are both global in scope, MeteoSwiss also takes part in cross-border cooperations and shares data internationally.

"In general, our experience with SWITCH is very positive," stresses Schäfer. "We value the personal contact we have with the experts, who ably assist us with even the most specialist problems. When we moved our computing centre, for instance, we needed a fibre-optic line from the old location to the new one. It all worked perfectly. We view SWITCH as a flexible, dependable business partner," he concludes.

Martin Schäfer is very satisfied with the high levels of availability, stability and performance SWITCHlan delivers: "Stability has never been an issue. In the four years I’ve been working at MeteoSwiss, there hasn’t been a single connection failure. When it comes to security, I can remember one incident where SWITCH-CERT reported an anomaly in our data traffic. It quickly supplied us with precise details, which allowed us to look into the problem and fix it without any damage being caused."

About the author
Anja   Eigenmann

Anja Eigenmann

Anja Eigenmann has worked at SWITCH since 2012 and is currently an editor for online and print media. She trained as a journalist and later completed a Master of Advanced Studies in Business Communications. She has previously been an editor-in-chief and consultant, among other things, and has led a course in online content writing.


Christoph Grab

Physicist Prof. Christoph Grab has been part of the Compact Muon Solenoid collaboration at CERN in Geneva since 2003. Since 2008, he has led his own research group at ETH Zurich’s Institute for Particle Physics. He coordinates the national computing resources for the Swiss activities concerning the physical analysis of data from the Large Hadron Collider.

Martin Schäfer

Martin Schäfer has a degree in physics from ETH Zurich. Since 2012, he has been Head of Information and Communication Technology at the Federal Office of Meteorology and Climatology (MeteoSwiss), where he is a member of the Extended Management Board.

What is SWITCHlan?

SWITCHlan is a high-speed network that was built in 1989 for education and research and has been continually optimised in line with their needs ever since. Thanks to a redundant fibre-optic network, it offers high levels of availability and supports bandwidths up to 100 gigabits per second, as much as 100 times more than conventional networks. It is connected to the European research network GÉANT, enabling high-bandwidth links to other research and university locations throughout Europe and overseas.

SWITCHlan is protected by SWITCH-CERT, the Computer Emergency Response Team, because research data are sensitive and increasingly targeted by cybercriminals.

All of this means that SWITCHlan is of interest to private research groups as well.

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