While those using a web application can easily reconnect, this caused problems for researchers using applications that need to maintain a consistent connection."You didn't know where the boundary was between where you could roam and where you couldn't - that was frustrating because sometimes it worked and sometimes it didn't."
The organisation is now rolling out Aruba 802.11ac Wave 2 access points and mobility controllers to help alleviate the connectivity issues. Cass explains: "We did a tender for the AC Wave 2 solutions with controllers and Aruba and other vendors bid. As a public organisation, it is a very much price-based open tender, but part of the testing that we did during that phase was definitely very interesting, showing what the Aruba RF performance was like."
The work is still underway, with 40 percent of the campus set to be upgraded by the end of this year, and plans to complete the deployment of up to 5,000 access points during 2018.
"It is a high-density deployment; we are deploying one access point every three offices and in some places where we have a 'Faraday cage' sort of construction we are even deploying one access point per office, because what I want especially is that people will see that the wireless environment performance is as good at least as the wired."
While the main aim of the project is to improve connectivity for researchers, there are a number of benefits to upgrading the wifi at CERN from a wider organisational perspective.
"There are a whole bunch of other business processes that people will be able to do when they can rely on people having a wifi connection," Cass says. "Our HR team have to print out pieces of paper and give people maps when they come for an interview, because they can't rely on the fact that they will have a wifi connection. This is because we don't have a guest network today, whereas [in the future] we will.
"Everybody expects a guest wifi network when they turn up - so you can say 'here is your schedule for the day'. Things like that will help people streamline what they are doing."
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