HOW SIM CARDS ACTUALLY WORKS?
![]() |
You most likely use it every day, yet if someoneasked you how it works, you’d have a hard time explaining it.
I’m not talking about physics here, it’s all about your SIM card, that little chip in your phone. So let’sfigure it out! When was it invented? First of all, have you ever wondered.
What SIM stands for?
It actually means subscriber identity module or subscriber identification module.The first SIM card in the world was developed in 1991 by the German company Giesecke & Devrient.
Who Discovered Sim Cards?
In 1992, they soldthe first GSM mobile phone with a SIM card; it was a Nokia 1101. Today, it’s hard tofind a person who’s never used a SIM card – over 7 billion gadgets around the worlduse them to make calls, send SMS and surf the web.
European Telecommunications Standards Institute
Experts predict this number is goingto grow to 20 billion in the near future. The European Telecommunications Standards Institute (ETSI) still holds the most SIM licenses, yet other private telephone companiesalso have some significant licenses because of which SIMs work.
Manufacturing of Sim Cards
The largest manufacturer of SIM cards in the world is the Gemalto company, with headquarters in Amsterdam and 15,000employees.
They’re now working towards the mass production of SIMs for 5G networks. The first SIM cards cost more than one dollar each to manufacture.
Today, they’re basically worth a few cents apiece. But that price doesn’t cover design, development, inserting chipsinto plastic cards and shipping them.
Why do We need a SIM card?
A SIM card has unique identification informationon it, like what mobile network it belongs to. It’s called an IMSI -International MobileSubscriber Identity. This unique ID connects your phone number with your gadget.

When someone is dialing your number, the call will go to the exact phone you have at the moment. SIM also has its own memory. Even though it’s really small – just 64 kilobytes – itcan store around 250 contacts and some SMS.
By the way, the same memory was in the ApolloGuidance Computer used for the first Moon landings. If your SIM card is mobile, meaning you can remove it and put it back into your phone yourself, you can also use it on differentphones.
This comes in handy when your own gadget’s battery is dead, and you desperatelyneed to make a phone call from your number.
Could Your phone will work without SIM card?
Technically it can, as a camera, or a devicethat connects you to Wi-Fi, but not as a phone to make calls or text someone.
For the absolutemajority of phones, a gadget without a SIM card is like a human without a brain. The good news is, even if you seriously damaged your phone - smashed your screen or bent thecasing - you could still use the same phone number and keep your contacts. All it takes is a SIM card transplantation.
How does a SIM card work?
A SIM card basically looks like a little piece of plastic. It has an even smaller chip inside that its Microcontroller.
It’s made out of silicone and plated with gold or othermetals to help it keep contact with the phone. The chip contains a processor, memory andsecurity circuits. Itcontains the operating system for the card, can do some basic math, and stores important information.
The most basic types of that information are your International Mobile Subscriber Identity and a 128-bit keycalled Ki (Key Identification). Those are basically your login and password in the mobilephone world.
keyto encrypt and decrypt of Sim Cards
The keyto encrypt and decrypt messages is also stored on the SIM card. This provides communicationprivacy. The SIM card chip also stores specific data, such as your card’s unique serialnumber, the name of your cellular carrier, your PIN (if you’ve ever wondered.
PIN-What it stands for?
by the way, it’s your Personal Identification Number to lock and unlockthe phone, PUK code from the carrier to unblock the phone and much more. Even your contactsand last dialed numbers are there.
Can someone track my location with the helpof a SIM card?
This is a question of both privacy and security.While it’s creepy to think someone can track your physical location for their purposes,it’s good to know your phone can be found when it’s lost or stolen.
And, it can also be helpful when it concerns lost kids or elderly people, for example. So, a SIM card can helpto establish your location, but it’s only one player in the “find me” game.
How To Insert Sim Card in Phone
When you insert a SIM in your cell phone, tablet, or even car, and turn the device on, it startsconnecting to cell towers to catch the signal.
As you move around, your SIM works with thetowers nearest to you to provide the strongest signal.
All these towers have known physically locations. When phone companies or the police use their algorithms to find out how strongthe signal is from this or that tower, they can narrow down the search area significantly.
Find My Device Using Sim Card
like "find my phone" likewise use WiFi information to know a more explicit location.Of course, it'll possibly work when the WiFi on your device is on.
Add GPS information to this, and you’ll get fairly accurate data on any gadget’s whereabouts in realtime.
So if you want complete privacy, turn it off, along with WiFi, and trackingyou down using information from your SIM alone will be a challenge.
Do SIM cards break?

SIM cards, like just about anything on this planet, can get damaged or broken and don’t last forever.
0 Comments