Google also described new technology for Project Fi that will allow users to move seamlessly from 1 million high-quality Wi-Fi zones to LTE cellular from Sprint and T-Mobile.
With the help of a special new SIM card in the Nexus 6, users are supposed to get access to the highest-quality connection on the fastest network, whether Wi-Fi or one of the LTE networks. Phones can access the better of the two LTE networks in any given location, according to Google's description.
"If you're on one network and we detect our other 4G LTE network partner has a stronger signal, you're moved over to the other network to get the fastest available speed," Google's website says.
While roaming between network providers has gone on for years, it is unique that Google, as a new MVNO (Mobile Virtual Network Operator), is able to do so. Menezes said the shared cellular network feature "could be the most revolutionary part of Project Fi."
Entner said it's likely that voice calls on cellular would still be carried via older GSM on T-Mobile and then connect to a different voice technology, CDMA, on Sprint. However, T-Mobile now has Voice over LTE in place, and other carriers are moving toward VoLTE. Google's description of Project Fi on its website refers to using LTE with both carriers, with no mention of GSM or CDMA for voice. Google couldn't be reached to clarify whether those older technologies will be used.
In any event, the claims that these various mobile connections will be automatic for Project Fi users remains to be seen. "Quality of service will need to be good," said Carolina Milanesi, chief of research at Kantar WorldPanel. "The moment you are trying to figure out why you have no coverage is the moment you give up."
A wireless industry disruption
While an AT&T official downplayed Project Fi as a niche idea, others see it as potentially disruptive in challenging rates and service approaches.
Menezes said that if the network-sharing features work well for Project Fi, both T-Mobile and Sprint may decide to extend a similar capability to their own postpaid customers.
As the major carriers have adapted pricing and no-contract approaches to T-Mobile's disruptions over the past year, Google could do the same.
"Google is not trying to take over the wireless market, nor do the major cellular carriers have anything to fear," said Jack Gold, an analyst at J. Gold Associates.
"Google is just trying to shake up the market, just as they did with Google Fiber in Kansas City, with Nexus phones when they thought no one was making a good enough phone, and with Google Voice. They are basically having a trial to see if the switching technology between Wi-Fi and cellular works as stated, something that people have been trying to do between networks for years with mixed results." T-Mobile offers connections from cellular to Wi-Fi, but the process is not automatic, Gold said.
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