2 phones 1 number

[lupi]

So I've all but tossed in the flag for the companies screwing many over like myself in their inability to provide a non-camera equipped phone.

What I want to know now is if I could get a second sim card, have it mirrored with the same info as the first so I could operate one phone when not at work and one while at work without having to either add a line or additional numbers.

 

[tatteredpotato]

You could use google voice, but that requires 2 lines.

You essentially want to pay for one line and be able to use two different phones on the same service? What company are you with?

 

[rudeguy]

There is no way. Each SIM has an ID and you can only have one SIM per phone number.

 

[tatteredpotato]

There is no way. Each SIM has an ID and you can only have one SIM per phone number.

I've never had a GSM phone, but can't you just switch the one SIM back and forth when you want to switch phones?

 

[rudeguy]

I've never had a GSM phone, but can't you just switch the one SIM back and forth when you want to switch phones?

Yes but you can't have 2 SIMS. Besides messing with the company's network, it wouldn't be E911 compliant.

 

[GaryJohnson]

Googling around it seems like most people say that it's possible with the technology, the carriers just won't let you do it.

The best you might be able to do is use call forwarding to go from one mobile number to another mobile number when unanswered after a certain number of rings.

 

[Pliablemoose]

It's possible, and the SIM card has actually been cracked IIRC, but no one's doing it, the advantage would be to get free phone service, not a legitimate reason as you likely have (you work in a secure area?)

The most likely best solution would be to go with a GSM solution and swap out your sim card away from work.

What phone do you have/want? Carrier?

 

[boomhower]

Yes but you can't have 2 SIMS. Besides messing with the company's network, it wouldn't be E911 compliant.

I thought one of the main features of SIMS was you could pop it out of one phone and stick it in another without having to deal with the carrier. (assuming you are using a normal phone and not doing iphone on t-mobile kind of thing)

 

[blackangst1]

This would be essentially cloning your SIM. Not advisable.

 

[rudeguy]

I thought one of the main features of SIMS was you could pop it out of one phone and stick it in another without having to deal with the carrier. (assuming you are using a normal phone and not doing iphone on t-mobile kind of thing)

right. You can have as many phones as you want but just one SIM. He was asking for 2 SIMs on one phone number

 

[Slick5150]

Cloning a SIM card is, as far as I know, illegal.

It would also cause many other problems.

 

[lupi]

There's only one thing I wanted to do less than swap out my sim twice a day, and that's pay for another plan.



Oh, and this is for tmobile.

 

[pm]

Right. As people have said, two SIMS with the same configuration are cloned SIMs and cloning GSM SIM's is illegal in a lot of countries, and is inadvisable regardless because carriers don't like it. Besides you'd need to crack the SIM encryption and that would be hard to do, as well as have a SIM programmer, which you could probably jerry-rig from a ROM programmer, but they aren't cheap.

I'm not sure what the US law on the subject would be, but I can say that if T-Mobile found that you had two phones active on the network at the same time, they would kill your account immediately and then follow it up with phone calls and emails for your to explain what happened.

On weird thing you could do is to get one of those piggy back SIM carrier things and then pull the SIM card out of the phone device. Basically buy a "extension cord" for your SIM with a fake SIM that plugs into the phone and then wires that run out of the phone to the real SIM. This would make it much easier to swap the SIM around.

I've seen something like this at sites like "dealextreme.com" but I can't remember what it's called so I can't find it.

 

[rudeguy]

from Wiki:

[edit] Authentication key (Ki)
The Ki is a 128-bit value used in authenticating the SIMs on the mobile network. Each SIM holds a unique Ki assigned to it by the operator during the personalization process. The Ki is also stored on a database (known as Authentication Center or AuC) on the carrier's network.

The SIM card is designed not to allow the Ki to be obtained using the smart-card interface. Instead, the SIM card provides a function, Run GSM Algorithm, that allows the phone to pass data to the SIM card to be signed with the Ki. This, by design, makes usage of the SIM card mandatory unless the Ki can be extracted from the SIM card, or the carrier is willing to reveal the Ki. In practice, the GSM cryptographic algorithm for computing SRES_2 (see step 4, below) from the Ki has certain vulnerabilities which can allow the extraction of the Ki from a SIM card and the making of a duplicate SIM card.

[edit] Authentication process
When the Mobile Equipment starts up, it obtains the International Mobile Subscriber Identity (IMSI) from the SIM card, and passes this to the mobile operator requesting access and authentication. The Mobile Equipment may have to pass a PIN to the SIM card before the SIM card will reveal this information.
The operator network searches its database for the incoming IMSI and its associated Ki.
The operator network then generates a Random Number (RAND, which is a nonce) and signs it with the Ki associated with the IMSI (and stored on the SIM card), computing another number known as Signed Response 1 (SRES_1).
The operator network then sends the RAND to the Mobile Equipment, which passes it to the SIM card. The SIM card signs it with its Ki, producing SRES_2 which it gives to the Mobile Equipment along with encryption key Kc. The Mobile Equipment passes SRES_2 on to the operator network.
The operator network then compares its computed SRES_1 with the computed SRES_2 that the Mobile Equipment returned. If the two numbers match the SIM is authenticated and the Mobile Equipment is granted access to the operator's network. Kc is used to encrypt all further communications between the Mobile Equipment and the network.

The simple answer is no but like everything...there are ways around it. But would it be worth all that?

 

[Pliablemoose]

Do you need data?

 

[pm]

Right, and once you'd done all that you'd still need to program up a new SIM with the identical information on it. Since they are pre-programmed to have unique numbers, you'd somehow need to overwrite that data, and then write the new data in - probably to do this, you'd need to somehow get a blank SIM, which would be hard to find since the only reason you'd want one would be to clone a SIM and that's a shady thing to do.

Also, both AT&T and T-Mobile recently changed the SIM encryption (recently being in the last four years) method. I'm not sure of the details, but I do know that on their 3G network, old SIM's don't work.

 

[Mark R]

Also, both AT&T and T-Mobile recently changed the SIM encryption (recently being in the last four years) method. I'm not sure of the details, but I do know that on their 3G network, old SIM's don't work.

While UMTS (3G) USIMs are backwards compatible with GSM equipment, GSM SIMs cannot be used in UMTS equipment.

 

[murphy55d]

Verizon has non-camera Blackberries.

 

[corkyg]

I have always wanted 2 phones on the same number. On land lines, we have 4 phones all on the same number. They are simply the same phone in different locations.

I have never understood why cell phones can't be used this way. I just accept it as another money grubbing tool.

Anyway, the company that can provide this will do very well. But, as of nowl, I see no takers.

 

[lupi]

Do you need data?

yes, key reason why simply getting another line is no good.

 

[lupi]

I have always wanted 2 phones on the same number. On land lines, we have 4 phones all on the same number. They are simply the same phone in different locations.

I have never understood why cell phones can't be used this way. I just accept it as another money grubbing tool.

Anyway, the company that can provide this will do very well. But, as of nowl, I see no takers.

i have never looked into it, by my BB instructions when i first looked through them had details about setting up more than one line for the phone.

 

[Pliablemoose]

yes, key reason why simply getting another line is no good.

Looks like sim card switching is the only practical option.

 

[rudeguy]

i have never looked into it, by my BB instructions when i first looked through them had details about setting up more than one line for the phone.

Phones have had dual NAM's (numbers) since at least 1999. The problem is having your phone number assigned to multiple devices at the same time.

 

[velillen]

I work in a similar situation...ie no camera phones (we get even more strict with sometimes no wifi phones and crap too) so heres pretty much the "top" methods ive seen people do

-SIM switching. Have a nice camera phone and just switch sim card to a cheap "go phone" at work

-Call forwarding. Leave your nice phone at home and have a crappy one for work but messages would be forwarded. Does cost more but only 10 for extra line i think

- Order phone with no camera. Just go into the store. 90% of phones can be orders without the camera. Will look identical to one with a camera just when you try to use camera itll say...no camera

- Pay as you go phone + normal phone. know a few people who just get one of those prepaid phones for work and have their nice phones for outside of work. Limits ya in you have to give people two numbers but also means you wont have people bugging you at work either.

Not that i helped but o well those are a few ideas!

 

[jersiq]

I have always wanted 2 phones on the same number. On land lines, we have 4 phones all on the same number. They are simply the same phone in different locations.

I have never understood why cell phones can't be used this way. I just accept it as another money grubbing tool.

Anyway, the company that can provide this will do very well. But, as of nowl, I see no takers.

It's an issue of effectiveness. Mobile Switching stations are built along different boundaries other than just geographical ones. Why is this important? Well, it helps to establish the idea of a "home" switch and a "roaming" switch. Even within your carrier you "roam" on your own network if you are not currently being served by your home switch.

The problem here is when you receive a call while "roaming". It is the responsibility of the phones home MSC to know where the phone is roaming and to establish a TLDN to the switch which is serving the phone. It is torn down after the call is routed, but it still has to be set up. TLDN's are finite, and the FCC maintains that you must keep enough TLDN's to handle all traffic requiring a TLDN.

Now take a scenario where you have three phones on one line, and each is being served by a different switch at the time of the call. In a metro area, this isn't uncommon. An incoming call now requires 3 distinct TLDNs just to route the call the the handsets. But again, they are finite. If you took this increase (even if it was two lines only) over n amount of handsets who have the feature, you can see how easy it would be to exhaust TLDN's in the course of just a few minutes worth of calling over an entire switching center.

There's also a timing issue in that customers would be quite upset if they didn't receive incoming calls on all their phones at the same time. This would require setting up delay timers, which in every instance annoys the calling party even more.

As more switching center elements become IP based, you could expect this feature to become more prevalent, but it's not quite there yet.