GSM (Global System for Mobile Communication) :
1. 4.2 billion subscribers worldwide.
2. Interchangeable Subscriber Identity Modules (SIM cards) allows users to easily upgrade handsets or change operations.
3. Hand limit on coverage per base station (35 km radius) makes it more efficient in urban areas.
4. More popular worldwide (excluding USA).
5. Example of carriers in US : AT&T and T- mobiles.
CDMA( Code Division Multiple Access):
1. 413 million subscribers worldwide.
2. Subscriber Information is embedded within the device, making it less flexible.
3. No limit on coverage per base station makes it better suited for rural areas.
4. More popular in the United States.
5. Example of carriers in the US : Verizon and Spirnt.