AT&T turned on its 4G wireless network Wednesday. The switch, however, was in the company’s marketing department. By relabeling its existing 3G network, the country’s second-largest wireless carrier joined the other major wireless players with so-called fourth-generation wireless technology, which promises mobile Internet speeds so fast that huge files can be downloaded in minutes and streaming video can be watched without the interruptions of earlier-generation technologies. As recently as September, AT&T executives had referred to the company’s current network, which runs on a technology it calls HSPA-plus, as 3G. But AT&T has subtly shifted its marketing message since then, now proclaiming “the nation’s fastest mobile broadband network” instead of the fastest 3G network. The 4G network claim is already being used by all the major wireless carriers but what is the real definition of 4G.

4G is downloads speeds of 100MB per second and at this time Verizon Wireless which has the fastest network with their LTE network rollout only has downloads speeds of 5 to 12MB per second less than one quarter of the 4G definition. The marketing departments of the major carriers did a great job changing the definition of 4G.

In March 2011 a satellite company Viasat will be introducing a true 4G network with downlink speeds of 100MB per second but at the beginning it will be only for military use and consumer use will still be a few years out.

ViaSat Inc. (NASDAQ: VSAT) has rescheduled the launch of its high-capacity satellite ViaSat-1 with International Launch Services (ILS) to summer 2011.

I wonder if they will claim to have 5G.