Most of us do not pay attention to such details as IMEI and IMSI numbers. When we have to, we don’t know what they are or even how to find them. Do we need to know them or how are they different from each other? These are important questions about your privacy and security. We’ll answer them in this post before it’s too late to find out.
Many of us have heard about the IMEI number as it is very helpful in finding lost smartphones. But what about IMSI numbers and what is their role.
Let’s find out.
1. What is the IMEI number
IMEI stands for International Mobile Equipment Identity. Each mobile phone (and other hotspot mobile dongles) is assigned a unique IMEI number, which is printed on the inside, usually behind the battery pack. They are 15 numbers in length. Phone makers assign unique IMEI numbers to each phone, and these numbers remain unchanged once recorded for the rest of its life. So even if you travel to other countries, telecom operators can identify and register the country of origin for selling the phone.
The GSM Association (Global System for Mobile) uses IMEI numbers to store them in a global mobile database which is also central to all network operators, phone makers and other eligible industry parties. Whereas in the normal course, the number is useful for determining things like using your subscription (voice calls, internet) and also if there are any quality of services issues. The IMEI number is just as important as the serial number on other products. Therefore IMEI numbers are used to determine the authenticity of the phone with registration through the SIM card. This means that a false or incorrect IMEI number can lead to the blocking of telephony services. Also, IMEI numbers only prove the authenticity of the phone and do not establish any direct relationship with the buyer. For example, you might have bought a new phone as a gift to your parents or spouse. Although you may be the buyer (technically), the end user of the phone will be different. I know this has nothing to do with some, but I just wanted to clarify.
Carriers often use it in exceptional circumstances such as detecting locked or invalid phones on the network used for suspicious activities. In the case of CDMA phones, manufacturers use different terms called mobile equipment identifier (MEID) or electronic serial number (ESN).
The IMEI number is the first thing a carrier’s customer care officer will ask if your phone has been lost or stolen.
2. What is the IMSI number
IMSI stands for International Mobile Subscriber Identity. The carrier assigns a unique number assigned to the SIM card they issue to their subscribers. IMSI numbers consist of 15 digits (not always) and can be used to find the subscriber’s country and mobile network, among other SIM-related details. It is linked to the SIM card rather than the phone itself.
It is worth noting that to protect the privacy of subscribers, telecom operators instead use another number called TMSI (Temporary Mobile Subscriber Identity) while providing services to the SIM owner. The carrier uses TMSI to communicate with the subscriber. They are much shorter and easier to transmit.
3. How to find IMEI and IMSI numbers
If your phone has a removable battery module, you can find the IMEI number printed under the battery. You could also find it printed on the original box, but you threw it away a long time ago, right? Alternatively, you can dial *#06# in the phone dialer app to reveal a popup with your IMEI number. They are usually 15 digits long and are programmed into the phone.
Do you notice two IMEI numbers in the screenshot above? That’s because I’m using a dual SIM phone, and both of them must be registered with the carrier. Usually, only the last few numbers differ in such cases. The carrier helps the carrier to identify and track these phones with IMSI numbers.
Many smartphones started showing the IMEI number in the About section under Settings. Check if your phone displays the IMEI number there as well.
As an end user, you do not need the IMSI number attached to the SIM card. Some mobile phone manufacturers include the IMSI number in the settings under the About or About phone section, but this is rare.
Note: Some apps also claim to help find them, but we don’t recommend them. This is not worth it, and there are opportunities to use the information to track the user in question. If you need it, contact your telecom operator.
4. When using IMEI and IMSI numbers
Since IMEI numbers are unique and cannot be changed easily, they are very useful in tracking and recovering lost or stolen phones. It is used to identify a mobile phone as all IMEI numbers are stored in a global record called Equipment Identification Record (EIR). Your telecom provider has the ability to blacklist or block the phone. When the phone is blacklisted across all networks, no SIM will work on it. This means that the phone is pretty much useless. I think the Wi-Fi is still working.
Hackers use aftermarket tools to make a quick profit by changing the IMEI number. This is called unblocking, and it is a criminal offense in many countries. These hackers use tools to assign a new IMEI number (also known as spoofing) to the phone so that it can be unblocked and used again with a different SIM. You can face the legal consequences of spoofing a mobile IMEI number if it is caught when it is used in nefarious activities.
On the other hand, when you move your SIM card from one phone to another, the same IMSI number is carried to the new phone with the SIM card. The IMEI number remains with the phone because it is associated with the phone. Telecom operators use the IMSI number to identify the customer and all services to which he has subscribed. This includes communication, messaging, the Internet, and other services provided by the Company.
5. Security concerns
It is important to protect the IMEI and IMSI from the prying eyes of nefarious apps and trackers. Hackers can use your IMEI number to track and identify your movements. Heck, they can even trick them into using financial apps after stealing your data.
On a related note, if you encounter a phone without an IMEI number, it is either an invalid or a fake phone. You should not buy this no matter how attractive the price is. How do you know if your IMEI number is valid? Well, you can match what appeared in the program interface with that printed on the back and the packaging box. Another way to check this is using the LUHN formula.
In the same way, hackers can use IMSI numbers to track users, intercept calls, messages, and hack mobile data. This is because the IMSI number is linked to the SIM card and is used directly to provide related services to the subscriber. Hackers can create a fake access point to capture the data associated with the IMSI number before relaying it to the nearest cell tower and back again. Many Hollywood movies show that call tracking trick and all. However, the actual use of such a technique is a very complex process. Not impossible though.
Since the IMSI number is tied to a SIM card and is used while communicating with cell towers, it can also be used to track a user’s movements. In this case, the location of the cell towers is used to triangulate your position.
However, IMEI and IMSI applications can be extracted through mobile applications to create a personal profile based on your usage pattern. For example, depending on your browsing activities, many companies can show you specifically targeted ads. And you might be wondering how did that company know you wanted to buy a new jacket? Well, it can be any app that you have blindly allowed to access any information on your phone. Why do you think your phone is spying on you? Well, this is how you get Personalized Targeted Ads from profiles that identify the personal.
Find the identity of your phone
The IMEI is associated with the phone and is used to identify the phone. IMSI is associated with the SIM card and is used to identify the subscriber and the services assigned to him/her. The IMSI goes from one phone to another using the SIM card, but the IMEI stays with the phone. As an end user, you will find IMEI useful to block lost or stolen phones.
This is the gist of it. It’s a good idea to store your IMEI number in a safe place so that when the time comes, you can quote it. If the IMEI number is visible in the Settings section, just take a screenshot and save the image to the cloud.