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Key milestones reached for the new campus-wide Wi-Fi service

State-of-the-art Wi-Fi coverage is now available in key buildings including – finally – a simple “visitor” Wi-Fi service

Key milestones reached for the new campus-wide Wi-Fi service

The renewal of the Wi-Fi infrastructure in Building 40 took place at the end of July. (Image: Anna Pantelia)

Almost a year ago, the CERN Bulletin featured an article on plans for a campus-wide Wi-Fi service for CERN. Several months have passed since then, and this new service has now been deployed in many buildings, including Restaurant 1, the Main Auditorium and the technically challenging Building 40.

More than 5000 Wi-Fi users in more than 20 buildings already benefit from the new Wi-Fi infrastructure. “The new Wi-Fi service is live now. Cabling works were the main activity last year but since April it’s been full steam ahead with deployment of the new access points,” explains Maria Alandes, leader of the Wi-Fi Service Enhancement Project. “We aim to deliver a full Wi-Fi service in all office buildings by autumn 2018.”

Advantages of the new Wi-Fi service

The new access points are centrally managed, which allows users to move around without losing their network connection — a feature much appreciated by users with access to the new service. “This new infrastructure also supports the latest Wi-Fi standard, 802.1ac, which can provide high throughput for compatible clients,” explains Vincent Ducret, the Network Engineer responsible for the Wi-Fi service. “One happy user reported symmetric speeds of 370 Mbps, more than double what was possible before the upgrade.”

Where is the new Wi-Fi available?

Many office buildings in Prévessin and Meyrin are now benefitting from the new Wi-Fi service – see the Further Information section for more details. A key milestone for the project was the activation of the new service in Building 40 in July. The design of Building 40, with its reinforced concrete walls and circular open space, meant that it was very difficult to provide good Wi-Fi coverage via the previous independent access points. Too few access points meant that some areas weren’t covered, but adding more created interference problems. “We now have 260 access points compared to 60 before and the central controllers ensure optimal Wi-Fi coverage throughout the building,” explains Quentin Barrand, a fellow working on Wi-Fi service configuration and support. “Our pre-deployment surveys highlighted problems for the closed offices with metallic walls in the circular part of the building” adds Adam Sosnowski, a Wi-Fi expert who worked on the layout plan for the access points. “We’ve installed one access point per office in these locations in order to provide a high-quality service.” As for public areas, the new service has been available in Restaurant 2, Building 33 and the Microcosm for some time and has just been activated in Restaurant 1 and the main building areas.

Visitor Wi-Fi service

The new Wi-Fi service means we can also now support a Wi-Fi service allowing people to identify themselves by a code sent to a mobile phone (rather than needing to be authorised by someone at CERN) and with their devices kept isolated from CERN’s internal network. This new Visitor service has been available in Building 33 and to Microcosm visitors since July 2017 and in Restaurant 2 since early September. Now that the new Wi-Fi service has been enabled in Restaurant 1, the new Visitor network will automatically be available wherever the new Wi-Fi service is present. (If you want to try the service out though, you can’t use a laptop or smartphone already registered for access to the CERN network; only unregistered devices can use this service — and remember, you won’t be able to access many internal network services, only those you can access freely from outside CERN.)

Further information

  • List of buildings where the service is already deployed here
  • Deployment status of each building in GIS here (Wi-Fi deployment by building)