A quick overview of wireless technologies is provided below.
SIM Management is covered in this SIM Management topic.
CDMA/TDMA/AMPS
These technologies are what most cellular phones use today in the United States.
CDMA - Code Division Multiple Access (each call gets a unique code that is spread over the available frequencies)
TDMA - Time Division Multiple Access (each call gets a certain portion of time on a designated frequency)
AMPS - Advanced Mobile Phone Service (analog cellular)
GSM
GSM, or Global System for Mobile communications, is a fast-growing digital wireless technology used by the majority of the world. It differs from TDMA/CDMA/AMPS in that GSM phones:
Use a SIM card, a removable smart chip.
Use narrow band TDMA.
Operate at either 900 MHz or 1800 MHz in Europe and Asia, and 850 or 1900 MHz in the US
SIMs
SIMs are the brains of a GSM phone, and are programmed to:
Identify the subscriber to the network.
Handle network authentication.
Provide data storage for basic user data and network information.
Benefits of GSM Technology
Uses encryption to make phone calls secure
It's easy to change phones; you put your SIM into a new handset and no programming is needed.
More functionality is available, such as internet access, MP3 player capability, camera capability, etc.
This table lists some of the differences between GSM and CDMA/TDMA technology.
GSM
CDMA / TDMA
Handset ID
IMEI, International Mobile Equipment ID (burned in)
ESN, Electronic Serial Number (burned in)
or aMEID, Mobile Equipment ID
(14 digits)Subscriber ID
IMSI, International Mobile subscriber ID, on the SIM
(15 digits)MIN, Mobile ID Number
(10 digits)SIM ID
ICCID, Integrated Circuit Card ID
N/A
Service Number
MSISDN, Mobile Subscriber ISDN
MDN, Mobile Directory Number
Note
The generic term, Service Number is typically used..
Network ID
PMN, Public (Land) Mobile Network, composed of a 3-digit MCC (Mobile Country Code) and a 2 or 3 digit MNC (Mobile Network Code)
SID, System ID (5 digit number)