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A modern telephony system at CERN

CERNphone, a softphone client for mobile phone and computer, will gradually replace fixed phones over the coming months

(Image: CERN)

Support for fixed phones at CERN will be gradually phased out over the coming year. These phones, which are connected to the ageing Alcatel PABX (private phone exchange)*, will be replaced by CERNphone. CERNphone is a softphone client, which is a piece of software that allows users to make telephone calls over the internet. It is available for Android and Apple mobile phones, as well as for Windows, Macintosh and Linux desktops and laptops. The migration is scheduled to be complete by mid-2023.

Using CERNphone will be no different from the way we now talk to friends and family using instant messaging applications (e.g. WhatsApp or Signal) rather than our home or mobile phones. And, just as such applications enable us to talk for free when connected to Wi-Fi and to be reachable anywhere, CERNphone allows us to be reached anywhere in the world via our CERN fixed number and will help reduce telephony costs for CERN. Many of us are already using CERNphone around the world, as you can see from the picture below.

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CERNphone worldwide usage over the past three months. (Image: CERN)

No extra costs are incurred** from calls made using CERNphone on your mobile phone when you are connected to Wi-Fi. When not connected to Wi-Fi, using CERNphone is also much cheaper than using your mobile phone subscription. For example, a call made on roaming in the United States with CERNphone costs just one hundredth of a call dialled on your mobile phone. Moving to softphones will also allow CERN to reduce electronic waste as the physical phones we have today – as well as the physical infrastructure that supports them – will not need to be replaced with hardware that then has to be thrown away in the future.

The migration to CERNphone will happen progressively throughout the year, so no action on your side is required unless you are contacted. However, if you would like to switch to using CERNphone sooner, please follow the migration and installation guide. Note that you don’t need a CERN mobile phone subscription to use CERNphone on an Android or Apple mobile phone, and calls do not cost you anything when connected to Wi-Fi (available in all CERN offices). If you do not have access to a Wi-Fi connection, you can still use the data available through your subscription. Costs are low: for example, you could talk on CERNphone for over three days and still not use up a 5 GB/month data contract.

CERN Telecom services

* In large organisations, “PABX” connect all internal phones to each other and to external networks. CERN relies on the Alcatel PABX, installed in the 1990s, and on TONE, a system developed in-house that is gradually taking over the functions of the Alcatel PABX.

** The cost of the call to CERN will be the same as for a call made from an office phone at CERN.