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Data Centre Interconnection: 1.6 Tbps between CERN and Bologna thanks to spectrum sharing

Pubblicato il 04 September 2023
Data Centre Interconnection: 1.6 Tbps between CERN and Bologna thanks to spectrum sharing

Thanks to an innovative multi-domain spectrum sharing, GARR and GÉANT have connected two data centers over 1000 km apart at 1.6 Tbps: the CNAF in Bologna and the CERN computing center in Geneva.

For the first time, GARR and the pan-European network GÉANT have successfully connected two data centres over 1000 km apart: the national computing centre CNAF of the Italian National Institute for Nuclear Physics (INFN) in Bologna, and CERN in Geneva, with a capacity of 1.6 Tbps and a latency of just 9.5 milliseconds, thanks to multi-domain shared spectrum.

The two data centres, in Italy and in Switzerland, can now seamlessly work together despite the distance and their different administrative domains. This solution provides a much faster connection with a larger and more scalable capacity at a fraction of the cost of upgrading a traditional packet connection. This milestone achievement uses the sharing of the optical spectrum of fibre between GÉANT and GARR, which is possible thanks to the innovative, partially disaggregated, optical network design of the two networks.

This CERN-CNAF Data Centre Interconnection (DCI) was built as a pilot project of the new GÉANT spectrum sharing service. This pilot initiative came in response to CERN’s challenge in processing the vast volume of data generated by the LHC experiments, which is expected to increase dramatically after the forthcoming High Luminosity upgrade for the LHC. As well as providing a much faster, and more scalable, connection between the two data centres for offline data processing, links such as this have the potential to enable data centres like CNAF to participate even more closely with the LHC experiments, not merely receiving data for later study but taking part in the high-speed, time-critical event selection that, until now, has been running at dedicated “trigger farms” located near the experiments themselves.

This pilot is one of the many results of the GÉANT (GN4-3) project, co-funded by the European Commission and by the European National Research and Education Networks (NRENs), and specifically of an activity aimed at creating a common model for spectrum-sharing interconnection among different NRENs.

The DCI connection between CERN and CNAF is an example of the potential offered by the GARR-T network, the new GARR infrastructure that allows connections to be reached at the speed of one Terabit per second.

More info: From Geneva to Bologna in 9.5 milliseconds