In the rush to overhaul mobile networks and roll out the red carpet for 5G, it's easy to forget that legacy connections still have their purposes. Many people still rely on 2G connections for voice, not having Voice Over LTE available on their network or device, and a great number of customers use 2G connections for what's called M2M, or machine to machine. In this type of low-data, high-speed transmission, one machine on a network forges a direct connection to another and they talk through it. The data throughput it usually minimal, but crucial content, such as server code, secure encryption codes, and configuration files for systemwide changes on an intranet. Customers who used M2M on AT&T's network to communicate between buildings and such, however, are finding themselves increasingly shown the door as AT&T refarms their 2G network. T-Mobile, it seems, is gunning for these customers.
It seems that T-Mobile's plan is to leave some of their 2G bands intact for the time being, 5 percent to be exact, to support M2M customers, who may come pouring in from AT&T as the rival carrier ousts them. T-Mobile has been working steadily on increasing support and coverage for the network technologies that allow Voice Over LTE, resulting in a fairly robust and reliable Voice Over LTE network. The refarming is a process and won't happen overnight, so those with legacy devices have nothing to fear for the time being. The refarming is happening mostly in step with the rollout of new LTE technologies like three-channel carrier aggregation and LTE-U, as well as preparation for a pending 5G rollout.
For now, continuing to maintain their legacy 2G networks as they are will keep things friendly for legacy device owners and those who aren't in good enough LTE coverage areas to rely on Voice Over LTE yet, and will help them to score a new subset of M2M customers. CFO Braxton Carter stated the conundrum quite succinctly, saying "Until you get voice and data on LTE, you can’t refarm spectrum dedicated to legacy technology,". According to AT&T's data, roughly 6 million AT&T customers still use their 2G networks, and almost all of those are M2M customers. While AT&T has been working on migrating many of those customers to newer technologies, a large number of them face searching for a new M2M solution, and T-Mobile is ready to catch them.