• Simply Put
• Data applications
• Where are GSM frequencies used?
• GSM history and technology

• GSM in the context of other communications technologies
• Glossary of GSM terms

Simply Put       

GSM, which stands for Global System for Mobile Communications, is a digital cellular radio network operating in over 200 countries world-wide.  It provides almost complete coverage in western Europe, and growing coverage in the Americas, Asia and elsewhere.

Of special interest is the capability of the GSM network to be used for data computing.  Most people think of voice calls when they think of cellular phones. But because GSM is digital, you can connect your GSM-enabled phone to your laptop computer and send or receive e-mail, faxes, browse the Internet, securely access your company's LAN/intranet, and use other digital data features including Short Messaging Service.

Because it uses radio frequencies, GSM is a wireless platform, in contrast to technologies which require connecting one's laptop modem to a telephone outlet to use the land-based telephone network. This means users of GSM can be fully mobile, and do wireless data computing anywhere, without worrying about adapters, telephone jacks, cables, etc.

The unique roaming features of GSM allow cellular subscribers to use their services in any GSM service area in the world in which their provider has a roaming agreement. That means the phone you use in France could work in Germany, Australia, Finland and even China, depending on your provider's roaming agreements.

GSM-enabled phones have a "smart card" inside called the Subscriber Identity Module (SIM). The SIM card is personalized to you and you alone. It identifies your account to the network and provides authentication, which allows appropriate billing.

No wires! This means connecting with the office: anytime, anywhere.

• Turn waiting time into email or fax time -- at the airport, train station, the dentist's waiting room.
• Turn any place into a productive work space: a hotel room, a client's office or home, the factory floor, a loading dock, a cafe table -- anywhere.

Data applications

When you connect your GSM-enabled phone to your laptop computer, what additional capabilities do you have?

• Internet

Because GSM is digital network, it provides the most ubiquitous and robust wireless data connectivity in the world. You can connect with transmission speeds of 9.6kbps and up. Simply dial your Internet Service Provider and you can access the Internet.

• Mobile Fax

Need to get a fax when you're away from the office? Just bring your GSM phone and your laptop PC and you have a mobile fax machine. With GSM you can receive and send faxes from any place there is GSM service, which means most of Europe, plus growing parts of North America and Asia.

• Secure corporate LAN Access

GSM provides solutions for securely accessing your corporate LAN. Unlike analog cellular communications, GSM encrypts the air link and provides additional security for your confidential email, faxes or files. Some GSM service providers can provide your company with a direct digital connection right from your GSM network to your corporate LAN.

• Short Message Service

Short Message Service (SMS) is an integrated paging service that lets GSM cellular subscribers send and receive data right on their cellular phone's LED display, up to a maximum of 160 characters. Combine this with your laptop, and you can receive urgent email, fax notifications, news and stock quotes -- all without even dialing the phone.You can receive messages even when you are making a call.

Where are GSM frequencies used?

GSM networks presently operate in three different frequency ranges. These are:

• GSM 900 (also called GSM) - operates in the 900 MHz frequency range and is the most common in Europe and the world.
• GSM 1800 (also called PCN (Personal Communication Network), and DCS 1800) - operates in the 1800 MHz frequency range and is found in a rapidly-increasing number of countries including France, Germany, Switzerland, the UK, and Russia. A European Commission mandate requires European Union members to license at least one DCS 1800 operator before 1998.
• GSM 1900 (also called PCS (Personal Communication Services), PCS 1900, and DCS 1900) - the only frequency used in the United States and Canada for GSM. Note that the terms PCS is commonly used to refer to any digital cellular network operating in the1900 MHz frequency range, not just GSM.  For more information on GSM 1900, visit http://www.pcsdata.com.
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GSM history and technology

Look at this paper for a discussion of GSM's history, services, network architecture, radio link (air interface) aspects, and network aspects:

Overview of the Global System for Mobile Communications, by John Scourias, University of Waterloo, Oct. 14, 1997

Glossary of GSM terms