AT&T, the exclusive iPhone carrier in the US, is apparently on its toes to improve its much-complained-about network – not merely to pacify the irked subscribers, but also to gear up for evident competition and comparison with Verizon Wireless network once the rumored iPhone version for Verizon is released.

The direct comparison with Verizon would likely not be a very encouraging situation for AT&T – largely because while Verizon happens to be the country’s most highly-regarded carrier, AT&T has clearly fallen short of providing satisfactory service levels to the iPhone subscribers.

In the opinion of Steve Beauregard - president of Santa Monica, California-based Regard Solutions -, the performance of the iPhone on the more efficient CDMA network of Verizon will be much better than the performance of its counterpart on the GSM network of AT&T.

Beauregard said: “It's widely held that a single CDMA tower can cover roughly the area of two GSM towers. In addition to the spectrum advantage, there are technical efficiencies of IS-95 [a CMDA standard from Qualcomm] that give Verizon a slight leg up over GSM rivals.”

Despite the fact that AT&T, which has noticeably poor coverage in cities like New York and San Francisco, is trying its best to reduce dropped calls and speed up Web-surfing, Edward Snyder, managing director of Charter Equity Research, projects a “huge exodus to Verizon” when its gets the iPhone.