The American telecom operator AT&T seems to be of plan to its gsm network in the long term to turn it off. In a letter to customers was sent out, called the telephone company to upgrade to a device that is suitable for 3g.
This alerts the provider that mobile devices in the future will no longer work. Although AT&T that there is not explicitly set, it seems that the gsm network will eventually be turned off. That will not be directly in the entire United States happen: the telco points to ‘certain areas’ where the 2g signal will no longer function.
In a comment let AT&T know only customers to want to encourage a new device to purchase. However, it is likely that there are any plans to have the mobile network off: the function is already years by 3g, acquired the telco can released gsm spectrum to good use for other purposes, such as the 4g network technology lte.
Previously tried AT&T to the American branch of T-Mobile to take over. This was, among others, the available netwerkspectrum be increased. The deal was eventually cancelled.