Cell Phone Useful information

[Texasdoc]

Though some of you would liketo know this info.


First - What to do when your cell phone gets lost...

Here is something worth knowing if you have a mobile phone .... Have you ever wondered why phone companies don't seem interested in trying to prevent the theft of mobile phones? If you have ever lost, or had one stolen, and if you are on a plan, you still have to pay the plan approximately up to 24 months, and you have to buy another handset and enter into another contract. This is more revenue for the phone company.

There is a simple way of making lost or stolen mobiles useless to thieves and the phone companies know about it, but keep it quiet. To check your mobile phone's serial number, key in the following on your phone: star pound zero six pound (* # 0 6 #) and a fifteen digit code will appear on the screen. This is unique to your handset. Write it down and keep it safe.

Should your mobile phone get stolen, you can phone your service provider and give them this code. They will then be able to block your handset, so even if the thief changes the sim card, your phone will be totally useless. You probably won't get your phone back, but at least you know that whoever stole it can't use/sell it either. If everybody did this, there would be no point in stealing mobile phones. You may want to send this to as many people with mobiles as possible.



Second - No charge for directory assistance. Phone companies are charging us $1.00 or more for 411 - information calls when they don't have to. When you need to use the 411/information option, simply dial 1-800-FREE-411 or 1-800-373-3411 without incurring a charge. This is information people don't mind receiving - Pass it on. Works on home phones and cell phones.

[TxBlonde]

Thank you. I copied and pasted it.

[BobCat]

Thank you!

I was skeptical and checked snopes. The free-411 information is true. Here is the link:

http://www.snopes.com/inboxer/nothing/free411.asp

Thanks again.

Regards,
Andrew

[Syntax360]

The "* # 0 6 #" didn't work on my Verizon Motorola. Doesn't the provider have the serial # on file? And isn't the number on the inside of your phone underneath the battery? And isn't the serial on your original sales receipt?

[cyphur]

Should be yes to all of the above, syntax. In any event, almost all cell phones are driven by SIM cards these days, or similar chips. When you report a phone stolen, the phone company disables the sim card's ability to associate to the network and use anything but 911.


The catch behind it is - if you hack the phone, make it "open" and slap a new sim card in - its good as new. So cell phone theft will continue to happen - you just won't be raped by the charges they incur(except of course for the replacement of a new phone - but thats why I always carried insurance).

[Mithras61]

The catch behind it is - if you hack the phone, make it "open" and slap a new sim card in - its good as new. So cell phone theft will continue to happen - you just won't be raped by the charges they incur(except of course for the replacement of a new phone - but thats why I always carried insurance).

Depends on the network. Some networks are CDMA and some are TDMA and some are GPRS. I'm pretty sure SprintPCS/Nextel use TDMA and everyone else uses CDMA or GPRS. They also have to have a network access code installed to be able to dial out to anything but 911 (yes, your phone logs in every time you turn it on - according to a tech I know at Sprint). Supposedly, if a SprintPCS/Nextel phone is stolen and disabled, and then has an "open" SIM card installed, it will still only dial 911 until it is reactivated at a Sprint Store.

I am not a cell phone tech, nor a cell phone junkie. Just reporting what I've been told by Sprint techs (who may be full of it).

[cyphur]

The catch behind it is - if you hack the phone, make it "open" and slap a new sim card in - its good as new. So cell phone theft will continue to happen - you just won't be raped by the charges they incur(except of course for the replacement of a new phone - but thats why I always carried insurance).

Depends on the network. Some networks are CDMA and some are TDMA and some are GPRS. I'm pretty sure SprintPCS/Nextel use TDMA and everyone else uses CDMA or GPRS. They also have to have a network access code installed to be able to dial out to anything but 911 (yes, your phone logs in every time you turn it on - according to a tech I know at Sprint). Supposedly, if a SprintPCS/Nextel phone is stolen and disabled, and then has an "open" SIM card installed, it will still only dial 911 until it is reactivated at a Sprint Store.

I am not a cell phone tech, nor a cell phone junkie. Just reporting what I've been told by Sprint techs (who may be full of it).

That is how I understand it as well. I was merely stating that contacting the phone company with serials and SIM card numbers protects your sim card only - the phone is still usable if you choose to hack it. Most phones like that are sold on the streets or on ebay. Then all someone has to do is walk up to a carrier and sign up w/o blowing $300 on the newest phone.

[Mithras61]

[quote="cyphur]
That is how I understand it as well. I was merely stating that contacting the phone company with serials and SIM card numbers protects your sim card only - the phone is still usable if you choose to hack it. Most phones like that are sold on the streets or on ebay. Then all someone has to do is walk up to a carrier and sign up w/o blowing $300 on the newest phone.[/quote]

Apparently I misunderstood your post. I thought you were saying simply replace the SIM card and voila! instant access to the cell phone network. My bad.

[comsec]

The following are the network protocols by major carriers in the US:

CDMA - Sprint,Verizon, Alltel, MetroPCS
GSM/TDMA - Cingular/ATT, T-Mobile

All mobile phones communicate on the air interface by an ESN or
Electronic Serial Number

The ESN is what makes every phone unique. If you know the ESN, then that is the preferred method of telling your carrier about a missing phone.

GSM phones have a SIM or subscriber identity module that is encrypted with the ESN to gain access to the air interface on GSM which is a form of TDMA.

The carriers have access to the asymmetric key algorithm for GSM/SIM authentication and can block/track a specific ESN/SIM combination from the home database(s).

CDMA phones have a unique spreading code for the spread spectrum emission used that is unique to every ESN. Again having the ESN is what counts here.

Most carriers will block an ESN of a stolen phone if you are persistent enough.

Ø comsec Ø

Principal Systems Engineer
Systems Engineering
*********** Wireless

[Venus Pax]

I was just about to post also on ESN.

Also, if you ever lose a phone, just buy a new one on ebay. Yes, many are stolen, but you can check it out before you bid by calling your wireless company and giving them the ESN. They can tell you if that phone has been stolen or if the person owes money. (If the person owes money, they will require you to pay it before connecting the phone.)
I did this when my cell phone was damaged.
If a seller won't list the ESN, then don't bid on it. Be sure and CHECK the ESN before you bid so that you know. I called in several and found out that they were either stolen or the owner owed money.