The current lack of a clear 4G definition has left many consumers in the dark about what they're really buying.
Sprint Nextel (S, Fortune 500) was the first to launch a network called 4G, going live with it in earlier 2010. It is based on a network standard called WiMAX, which is capable of speeds ranging from 3 Mbps to more than 10 Mbps.
Time for Verizon to buy Sprint?
T-Mobile soon followed suit, claiming at the time to be "America's largest 4G network." But T-Mobile's 4G network is actually an expansion of its existing 3G network, which operates on a standard known as HSPA+. Despite not being true "4G," T-Mobile's network can reach speeds of 5 Mbps to 12 Mbps -- faster than Sprint's.
Verizon (VZ, Fortune 500) launched its 4G network late last year, and it now claims to be the nation's largest and the fastest. The company's 4G network operates on the Long Term Evolution (LTE) standard, which will average 5 Mbps to 12 Mbps speeds.
AT&T (T, Fortune 500), which is expected to unveil its 4G-LTE network in the coming months, decided not to be the lone major carrier without a 4G network. So earlier this year, the company also began calling its 3G-HSPA+ network "4G." That means AT&T will soon have two 4G-branded networks, each using different technologies -- and its current 4G offering could, in some instances, be faster than its soon-to-be-released, new 4G network.
