AT&T To Acquire T-Mobile USA
No upside to GSM now...
Recall that GSM is much more modern technology...it was developed in the 1980's and first implemented in 1991....CDMA was first developed by the British during World War II and then put on a shelf for decades after the war.
The entire point of the SIM card is to provide security, because the SIM card is what 'cracks' the encryption, it is the decoder ring so to speak and allows the phone to access the network. CDMA has nothing comparable.
CDMA isn't perfect though. It takes some high dollar equipment to clone it but it happens.
T Bone said:
Recall that GSM is much more modern technology...it was developed in the 1980's and first implemented in 1991....CDMA was first developed by the British during World War II and then put on a shelf for decades after the war.
No, this is wrong. You are not referring to CDMA. You are referring to spread spectrum communication, specifically frequency hopping spread spectrum, which actress Hedy Lamarr & composer George Antheil invented during WWII.
CDMA utilizes direct sequence spread spectrum, which is more modern than the combination of TDMA & GMSK employed by GSM. Scrambling is inherent to CDMA, as each user's data is XOR'd against a cyclical PN long code that is over 41 days long.
AJ
John B.
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