The GSM (Global System for Mobile Communications) is a hugely successful wireless technology in the world. GSM has become the world’s largest growing communication technology and it has been expand in more than 214 countries of the world. The TDMA technology provides the individual time slot within a specific channel for each user.
GSM leads the world as the fastest growing mobile/wireless digital technology that is most reliable and is available in the marketplace today. GSM provides the integrated high-speed data, fax, voice mail, paging and short messages services features. GSM offers the secure communication, privacy and fraud prevention.
After subscribing to the GSM service, you can use your phone at your home, office, across the continent or around the world with the country specific SIM cards. GSM operates on the different frequency levels like 900 MHz, 1800 MHz or 1900 MHz.
1900Mhz is used in the North America and 1800 MHz is for the other locations. Different mobile phone networks around the world operate at different frequencies. If you wish to use your mobile phones outside of your GSM frequency range then you should use a mobile/handset that support multiple frequencies. Before buying a mobile phone, make sure that it is compatible with the different bands of the GSM.
Dual-band – A dual band phone operates at different spectrum like 900 MHz and 1800 MHz. Dual-band GSM works in Europe, Asia, Africa, Australia and Sound America.
Tri-band – A tri band phone operates on the three different frequency levels like 900 MHz, 1800 MHz and 1900 MHz. This means that you can use your mobile phone in Europe, Asia, Australia, Africa and North America.
Quad-band – A quad band GSM capable phone allows you to roam almost everywhere in the world. It covers the different frequency ranges like 850 MHz, 900 MHz, 1800 MHz and 1900 MHz. 99% countries in the world use the GSM standard and it seems that GSM will eventually be the only cell phone standard in the mobile communication world. GSM provides the best voice quality and standard.
Today, there are more than 720 GSM mobile networks across the more than 214 countries. According to the recent statistics, there are more than 2 billion users of the GSM in the world. Major GSM using countries includes China, Russia, United States and India. A mobile phone can be a bewildering affair for a traveler. It is mostly incompatibility with the network of your visiting country, since every country in the world has different frequency band of operation. With a GSM enable mobile phone you can access more than 214 countries around the globe.
GSM is a state of the art technology offering voice, data, fax and SMS capabilities. Most of the mobile phone operators now offers email to SMS service by which you can receive the important news, flight status and other useful information on your mobile phone. Many operators give access to the ISDN services by which fast data transmission is possible. Many other offers GPRS (Global Packet Radio Service) with this service you can connect to the high speed data communication channel like 9600 bps. The two major GSM service providers in the US are the T-mobile and Cingular.
The iPhone 4 is one of the most popular quad band enabled mobile phones currently on the market, it's a good idea to compare prices before you buy. Sites such as Mobile Phone Genie allow you to find the best iPhone deals.