difference betwwen CDMA and GSM networks

[aneesholv]

Why GSM have SIM card and CDMA have no SIM ? Please tell me the difference between them ?

 

[ckshivaram]

this is already discussed many times here... its better to do a search before posting question,,,,

https://www.edaboard.com/threads/199476/
https://www.edaboard.com/threads/57502/

---------- Post added at 14:08 ---------- Previous post was at 14:02 ----------

CDMA technology does not use SIM cards in the US and in many countries. CDMA phones have to be activated by the carriers. Even though people have taken to flashing CDMA phones to be used on other carriers networks..
CDMA services do not have SIM Cards. Instead, they have an ‘ESN’ number, which is a serial number attached to the mobile service. When a CDMA service is barred its ESN is blocked which negates the need for IMEI blocking because a CDMA handset cannot be used when an ESN is blocked.