What is SIM Card ?

Its a Metal, covers with piece of plastic, we use to insert in mobile phone is know as Subscriber's Identity Module SIM was identified by two numbers that is Integrated circuit card  Identifier ( ICC-ID) and International Mobile Subscriber Identity number

The Sim card contains along with text messages, phone contacts, and call history with date and time. This information cannot stolen by mobile operater it is always confidential to user

Security Systems on the SIM

First, the SIM card carries an authentication protocol in the form of algorithms and keys so that no unauthorized user can access your information remotely. Second, a cryptographic language guarantees your privacy by encrypting your data, decoding it when appropriate, and confirming when the information reaches its destination. Third, the SIM card carries a fraud protocol that prevents alteration of data or receiving services that have not been paid for.

• The network will protect our sim card with a PUK code
• It has maintained 1 mm thickness.

Specification of SIM Card

SIM Card pin diagram

SIM Card Components 8 PIN

1. 2 optional Pads for USB

2. Clock
3. Reset
4. VCC (Power Supply)
5. GND
6. VPP
7. I/O

Sim Cards Pinout 6 pins

Sim Card pins

and also we can describe sim card in PINs threre are 8 pins in SIM card.

1. VCC (power supply)
2. RST ( Rest)
3. CLK (Clock)
4. D + (USB Inter-chip)
5. GND (ground)
6. VPP (Voltage programming power)
7. D- (USB inter-chip)

Sim Card pins Explained

VCC 

VCC is an electronics designation that refers to voltage from a power supply connected to the "collector" terminal of a bipolar transistor. In an NPN bipolar junction transistor, it would be +VCC, while in a PNP transistor, it would be VCC

VPP 

VPP is the programming power voltage. In short, it is only necessary if you intend to change or write to the internal memory of the SIM card

GnD

GnD : This pin is the GROUND reference for the integrated circuit and associated signals. Care must be taken to avoid voltage spikes when the device operates in a normal operation.

More information from users what they feel in real life.

Fake cell towers are becoming common. Hackers use the IMSI and MSIN to do reverse lookup. They obtain subscribers name and address through publically available databaases and caller ID lookup tables. Then find lookup addresses and other information. Then, the next time the user connects to the fake tower a fake call is initiated and they pretend to be someone important and provide you with the information they gleaned thus attempting to gain your trust. They ask for more information to steal identity.