Telephone operator change: your questions answered

CERN will be changing mobile telephone operators on 24 June. As the community prepares for the summer switchover, everyone has questions. What brought on the change? Why are we losing our old phone numbers? What kind of improvements will we see?


"Just as with every contract at CERN, we issue calls for tenders every few years to ensure we are still receiving the best possible service," explains Tony Cass, from the Communication Systems group within the IT department. "As we came to the end of our contract with Sunrise, we put out a call for tenders, which was won by Swisscom. Not only is their pricing more competitive, they will also be providing better service conditions."

The scope of these new service conditions is multifaceted: there will be improvements to the redundancy and reliability of the network as well as modern 4G network coverage in the LHC tunnel. "People will also see their mobile phone bills decrease," says Tony. "This will especially be the case for people who travel, as roaming charges for data and calls will drop significantly."

In order to ensure a seamless transition between the two networks, Swisscom set about establishing a network that could operate in parallel with that of Sunrise. Together with CERN's IT and EN departments, some 50 new Swisscom mobile network stations have been installed across the CERN site over the past few months – quite an achievement as such stations normally take more than a year to set up! All this work means that, when the Swisscom numbers are activated on 15 June, there will be an overlap period with Sunrise. Users will be able to test their new mobile services before the switch on 24 June.

Which bring us to the question of the hour: why does CERN have to change its telephone numbers? "If you are an individual subscriber, you have the right to move your active number from one provider to another," explains Tony Cass. "While this same rule applies to CERN, the problem is the term 'active'. CERN is allocated 10,000 numbers, but only about 6,000 of those are 'active'. Were we to switch our numbers to Swisscom, we would lose some 4,000 numbers. Also, when a subscription ends, the rules say the number goes back to the original operator.” So, although it would be possible for current users to keep their ‘old Sunrise’ number, new users would have to have a 'new Swisscom' number and this inconsistency would lead to confusion.

But what if all 10,000 numbers were activated, switched to the new provider and kept active? "In addition to the financial implications, such a switch would be extremely chaotic," says Tony. "Switzerland only allows 500 numbers a day to change providers – meaning it would take at least 20 days to migrate all of CERN's numbers. It would be a complete nightmare, as users would not know which numbers were working when."

In short, while it may have been technically possible to keep the old CERN numbers, in the longer term this would have led to more extensive complications for users. "We realise that between changing SIM cards and contact lists, the change is a big hassle. It's something that the people in our team have to contend with as well. But if you look at CERN globally, it was definitely the best decision," concludes Tony.


For more information about the change, see the Bulletin announcement: "Change of mobile telephony operator and mobile telephone numbers - 24 June 2015”.

by CERN Bulletin