GSM a so supports advanced messaging and Internet uses of the wireless network. Such uses are known in the industry as 3G, because they represent the third-generation of wireless telephony including wireless-data devices.
"The main thing GSM does for us is provide support for advanced devices," says Robert Holliday, vice president and general manager for Cingular Wireless' Upstate region.
The Cingular system still supports the original analog and digital phones of the previous two generations of wireless technology. Holliday doesn't see the company shutting off older technology anytime soon, but he says Cingular has always encouraged its long-time customers to update their handsets to accommodate advances.
GSM is the technological framework for wireless-telephone systems outside North America. Like the separate North American standard used for television, wireless companies opted for technology that was different than that used in most other markets worldwide. Most wireless phones in the Western Hemisphere operate using the TDMA or CDMA wireless standard.
Cingular has roaming agreements with 150 carriers in 75 countries, says Holliday. The agreements allow Cingular customers to use their phones overseas and have any charges billed on their monthly statements. The carrier completed a $3 billion GSM update to its nationwide network earlier this year and began offering GSM-capable handsets in August. Cingular offers 16 GSM handsets with a range of features made by Motorola, Siemens, Sony Ericsson, and Nokia.
GSM handsets differ from other wireless phones through the use of a Subscriber Information Module, commonly known as a "SIM card." The card stores all the user's account information and other data such as telephone numbers. Moving the card from one phone to another turns that phone into the user's phone. The capability allows users to own several different handsets, says Holliday.
"Some of our customers own multiple handsets," he explains. "They can use a heavy-duty one for work and switch to a lighter model during leisure time."
If a telephone is damaged, the user can simply transfer all the telephone's information to a new handset, eliminating the need for extensive reprogramming.
Subscribers who travel overseas may choose to take only their SIM card with them. Even though wireless systems worldwide may use different handset frequencies, the SIM card will function on all GSM networks.
Prior to the introduction of GSM technology in the United States, consumers who needed wireless service overseas had to arrange for a separate account during their stay. Two of the new Cingular GSM phones can roam seamlessly across systems that use different frequencies.
In addition to the roaming capabilities of 3G, the GSM technology supports messaging between telephones across GSM systems. Though he knows of no current plans to implement a Cingular GSM-powered worldwide "push-totalk" system, Holliday wouldn't rule out the feasibility of such a system in the future.
