GSM IMEI SIM card question

Just wondering, is there any legitimate
(translation - network necessity) for a
GSM operator (Cingular in this case), to
have the IMEI number of a phone ?

I'm doing a number port, and they want
to know the IMEI of the phone.

My understanding is, the SIM card does
NOT contain this information. So why do
they need it ?

But reading the service manual of the
phone, it says the IMEI is what the network
operator uses to identify the phone.

Is the IMEI part of the signalling going
over the air ?

But, if that was the case, then it would
seem to defeat the purpose of a SIM card.
Which is, I can plug any SIM card into any
unlocked network compatible phone and it
should work.

My concern (given Cingular's bad rep) is
the information would some how backfire at
some point in the future if I tried to use
a T-Mobile SIM.

Any network engineers knowledgeable on this
topic ? Do I need to give out the IMEI info?
(given I'm using a prepaid SIM right now with
no IMEI information given out originally).

---

› See More: GSM IMEI SIM card question

Sisko wrote:

> Just wondering, is there any legitimate
> (translation - network necessity) for a
> GSM operator (Cingular in this case), to
> have the IMEI number of a phone ?

Not up front like that, there isn't. They'll be able to get it
from their network the moment the phone first registers with a
suitable SIM in it.

> I'm doing a number port, and they want
> to know the IMEI of the phone.
>
> My understanding is, the SIM card does
> NOT contain this information. So why do
> they need it ?

Usually, to see if the phone's on a stolen list (blacklisted).
But that gets done (if at all) each time the phone registers
with the network.

> But reading the service manual of the
> phone, it says the IMEI is what the network
> operator uses to identify the phone.

The phone, yes. But not the SIM (or, consequently, the phone
number).

> Is the IMEI part of the signalling going
> over the air ?
>
> But, if that was the case, then it would
> seem to defeat the purpose of a SIM card.
> Which is, I can plug any SIM card into any
> unlocked network compatible phone and it
> should work.
>
> My concern (given Cingular's bad rep) is
> the information would some how backfire at
> some point in the future if I tried to use
> a T-Mobile SIM.
>
> Any network engineers knowledgeable on this
> topic ? Do I need to give out the IMEI info?
> (given I'm using a prepaid SIM right now with
> no IMEI information given out originally).

I guess they can insist, but I have no idea why they'd bother.
They don't in civilized countries.

John

When I signed up with TMo I never gave them the IMEI. They gave me a
free phone so maybe they recorded the info but I sold that phone the
next day and put the SIM in a v600 I bought in Hong Kong. 9 months
later I switched to a v3 by just putting the SIM in the new phone. So,
while there may be a reason that they'd LIKE to know the IMEI they
certainly don't need to establish service.

From:Sisko
[email protected]

> Just wondering, is there any legitimate
> (translation - network necessity) for a
> GSM operator (Cingular in this case), to
> have the IMEI number of a phone ?
>
> I'm doing a number port, and they want
> to know the IMEI of the phone.
>
> My understanding is, the SIM card does
> NOT contain this information. So why do
> they need it ?
>
> But reading the service manual of the
> phone, it says the IMEI is what the network
> operator uses to identify the phone.
>
> Is the IMEI part of the signalling going
> over the air ?
>
> But, if that was the case, then it would
> seem to defeat the purpose of a SIM card.
> Which is, I can plug any SIM card into any
> unlocked network compatible phone and it
> should work.
>
> My concern (given Cingular's bad rep) is
> the information would some how backfire at
> some point in the future if I tried to use
> a T-Mobile SIM.
>
> Any network engineers knowledgeable on this
> topic ? Do I need to give out the IMEI info?
> (given I'm using a prepaid SIM right now with
> no IMEI information given out originally).

In <[email protected]> "BruceR" <[email protected]> writes:

>When I signed up with TMo I never gave them the IMEI. They gave me a
>free phone so maybe they recorded the info but I sold that phone the
>next day and put the SIM in a v600 I bought in Hong Kong. 9 months
>later I switched to a v3 by just putting the SIM in the new phone. So,
>while there may be a reason that they'd LIKE to know the IMEI they
>certainly don't need to establish service.
They use it to track stolen phones. At least they're supposed to.

Konstantin
--
Dipl-Inf. Konstantin Agouros aka Elwood Blues. Internet: [email protected]
Otkerstr. 28, 81547 Muenchen, Germany. Tel +49 89 69370185
----------------------------------------------------------------------------
"Captain, this ship will not survive the forming of the cosmos." B'Elana Torres

Konstantinos Agouros wrote:
> In <[email protected]> "BruceR" <[email protected]> writes:
>
>
>>When I signed up with TMo I never gave them the IMEI. They gave me a
>>free phone so maybe they recorded the info but I sold that phone the
>>next day and put the SIM in a v600 I bought in Hong Kong. 9 months
>>later I switched to a v3 by just putting the SIM in the new phone. So,
>>while there may be a reason that they'd LIKE to know the IMEI they
>>certainly don't need to establish service.
>
> They use it to track stolen phones. At least they're supposed to.
>
> Konstantin

Exactly, but unless they are forced by Government regulation to track
and block stolen phones from the network they will more than likely
ignore them because they want the revenue from calls made from the
stolen phones!


--
The views I present are my own and NOT of any organisation I belong to.

73 de Simon, VK3XEM.
http://www.aca.gov.au/pls/radcom/cli...IENT_NO=157452
VoIP http://www.TALKonIP.com.au/

In <[email protected]> Simon VK3XEM <[email protected]> writes:

>Konstantinos Agouros wrote:
>> In <[email protected]> "BruceR" <[email protected]> writes:
>>
>>
>>>When I signed up with TMo I never gave them the IMEI. They gave me a
>>>free phone so maybe they recorded the info but I sold that phone the
>>>next day and put the SIM in a v600 I bought in Hong Kong. 9 months
>>>later I switched to a v3 by just putting the SIM in the new phone. So,
>>>while there may be a reason that they'd LIKE to know the IMEI they
>>>certainly don't need to establish service.
>>
>> They use it to track stolen phones. At least they're supposed to.
>>
>> Konstantin

>Exactly, but unless they are forced by Government regulation to track
>and block stolen phones from the network they will more than likely
>ignore them because they want the revenue from calls made from the
>stolen phones!
The operators don't have that much revenue. However they track the IMEIs
for Marketing information. What better way to know which phones are actually
used in the network.

Konstantin
--
Dipl-Inf. Konstantin Agouros aka Elwood Blues. Internet: [email protected]
Otkerstr. 28, 81547 Muenchen, Germany. Tel +49 89 69370185
----------------------------------------------------------------------------
"Captain, this ship will not survive the forming of the cosmos." B'Elana Torres

There is some level of security to be performed on the mobile equipment
itself, as opposed to the mobile subscriber. Each GSM terminal is
identified by a unique International Mobile Equipment Identity (IMEI)
number. A list of IMEIs in the network is stored in the Equipment
Identity Register (EIR). The status returned in response to an IMEI
query to the EIR is one of the following:

White-listed
The terminal is allowed to connect to the network.
Grey-listed
The terminal is under observation from the network for possible
problems.
Black-listed
The terminal has either been reported stolen, or is not type approved
(the correct type of terminal for a GSM network). The terminal is not
allowed to connect to the network.

"Sisko" <[email protected]> wrote in message
news:[email protected]...
>
> Any network engineers knowledgeable on this
> topic ? Do I need to give out the IMEI info?
> (given I'm using a prepaid SIM right now with
> no IMEI information given out originally).

Just give it to them. It does go out over the air along with the SIM
information. Although after you "sign up" the carriers don't use it and
changing phones really is as simple as moving the SIM from one phone to the
other.