Some technical background: CDMA = Popular term for the mobile phone standard Verizon and Sprint use GSM = Popular term for the mobile phone standard AT&T and most other carriers use ESN = Electronic Serial Number. Unique hardware ID for a CDMA phone/device. IMEI = International Mobile Equipment Identity. Unique hardware ID for a GSM phone/device. SIM = Subscriber Identity Module. GSM phones have them. They have their own unique IDs.
SIMs identify you to the network. Your phone number and service are associated with your SIM, not the phone. Your phone book is on the SIM, too. SIMs can be swapped between GSM phones at will. With CDMA, your account is associated with the ESN of the phone. Changing devices needs the carrier to intervene. Some GSM phones are sold "locked" to a particular carrier/SIM. That means the phone's firmware is programmed to refuse to work if it doesn't like the network/SIM it gets. On Tue, Apr 1, 2008 at 3:08 PM, Rod Trent <[EMAIL PROTECTED]> wrote: > I don't understand it, either. But, they suggest that if a phone is stolen, > they can turn off the phone from anywhere, whereas, with a SIM card, it > can't be done. Verizon can turn off a Verizon phone from anywhere on the Verizon network, because they own everything. If you report your GSM phone stolen to your carrier, they can flag the IMEI as such. Even if the thief buys a new SIM and puts it in your stolen phone, they'll still see the stolen phone on their network. They can turn it off, or track it down. The complication arises when you're in an area that's serviced by a carrier that isn't on good terms with your carrier's home jurisdiction. They don't have any incentive to cooperate. If CDMA takes off world-wide, then you'll get the same situation. Scenario: Your Verizon phone is stolen. The thief takes it to the disreputable carrier in China or Korea or whatever, and says their brother-in-law gave it to them, and now they're up and running with your phone. If Sprint and Verizon weren't sharing CDMA infrastructure in the US, it would be happening here today. So if you only travel in the US, GSM is as secure as CDMA. If you go overseas with your international CDMA phone, you're just as vulnerable. -- Ben ~ Upgrade to Next Generation Antispam/Antivirus with Ninja! ~ ~ <http://www.sunbelt-software.com/SunbeltMessagingNinja.cfm> ~
