If you're an active mobile phone user, you will notice that your phone can actually make emergency calls without any SIM. I know you must be wondering how this is possible since there's no mobile number. Let me explain how your SIM works. SIM as you ought to know stands for Subscriber Identification Module and it helps to identify the cell service subscriber that is trying to connect to the network. Every user has their own SIM, so network providers can direct calls to that specific phone and track usage (and charges) individually. The identifying number of a SIM card is called an ICCID.






The IMEI is like the DNA of a phone; all phones can be identified just with their IMEI. This is a logical example of what happens when you call your friend with a SIM card:
Michael’s phone to cell tower : My IMEI is 123 and my ICCID is 456. I want to call +234-123–456–7890, please!

Cell tower: IMEI is 123, ICCID is 456; 456 is Michael’s account. I’m from Michael’s cell phone carrier and provide him with service, Michael has 100 minutes left in account, connecting call.

Michael : Thanks!



Now This is what happens when you try to call a friend without a SIM card:

Ade’s phone to nearby cell towers: My IMEI is 123 and I don’t have any SIM card. Please let me call +234-123–456–7890, please!

Cell Tower: Who's this one again ? Are you normal? You didn't even subscribe to any services, or even my own network ; why should I give them to you for free? Gerrarahia Mehnn!

Ade : Chai!

That sounds quite interesting, right? In the first instance, the cell tower allowed Michael to place the call because it knew who he was and that he was paying for it, but in the second, Ade was unsuccessful in placing the call because the tower had no idea who it was and didn’t want him using the service for free. It's like allowing a total stranger into your home.

Now what if the person on the other side of the door was involved in a terrible accident , on fire, or getting robbed ? What would the cell tower do?


Musa calling 911 or 112 with SIM card:

Musa’s phone to cell tower: Help Musa is dying! My IMEI is 123, my ICCID is 456, my latest location is 123 Musa’s Place, please connect to emergency services!

Cell tower: I can see Musa’s info with ICCID #456 and your latitude and longitude coordinates, connecting to Emergency Number!

Musa : Help, I’m on fire!

As you can see, 911 was able to receive information about Musa thanks to his ICCID and GPS coordinates.

Rochas calling 911 without a SIM card:

Rochas' phone to all nearby cell towers: Hello, please anybody around , help! Rochas is on fire!

Nearby cell tower: I’ll take the call! I really don’t care who you are, but I’m willing to help! Your IMEI is 123, meaning that you’re a Black variant of the Tecno Phantom 8, and your location is 123 Rochas’ Place! Connecting to Emergency number because I’m nice and I don’t want you to die yet !

Rochas : Help oh ! Rochas still got the help he needed, even with no SIM card. The emergency services would’ve been unable to receive much detailed personal information on John, but they knew his location and would be able to get there quick.


To round it up, cell phone towers are a lot more like paranoid kids staying at home for the first time. They won’t let you in if you don’t know their “secret password” lol, but are kindhearted enough to accept your pleas to help no matter who you are. So next time you’re in an emergency, don’t let “no service” fool you.

http://www.naijatechguy.com/2018/01/this-is-why-your-smartphone-is-able-to.html

Nice one

Learnt something new today. Thanks OP.

Are you talking about Nigeria or other country's?

inedujac:
Are you talking about Nigeria or other country's?

seriously? this is lame. some pple just find every avenue to rubbish this country. FYI emergency call without sim card works in Nigeria. Done it before.

NaijaTechGuy, When will our smartphones start making video calls without data?

Unto tech updates,

Check out these 3 Things The New Nokia 8 Can Do That Your Infinix or Tecno Phone Can't Do

ok

Even Nokia torch dey call 911... why not Android?

just finished calling 911 from okeho now. rescue team is coming from ibadan.. 5hrs journey lol

ORIJIN201:
seriously? this is lame. some pple just find every avenue to rubbish this country. FYI emergency call without sim card works in Nigeria. Done it before.

Thank you for your loyalty.

Good one

Story

closed

nice

nice..Your explanation was quite simple and easy to understand. I wish my Lecturer can be like you instead of dropping big grammar everytime.

Common terms used in the writeup


IMEI: International Mobile Equipment Identity

ICCID: Integrated Circuit Card Identity.

Ñairaland's problem is that important subjects like this rarely make it to the front page and when they do, the response is always slow and uninspiring.

Let lalasticlala post a thread showing Toke Makinwa wearing a see-through blouse and sit back see it go viral in 5 minutes.

naijatechguy deserves an award for best tech articles writer here in Nigeria. please I need backlink for this article below
https://extraloops.com/tech/mastering-google-search-engine/

inedujac:
Are you talking about Nigeria or other country's?

dumb question

An answer you could have given in one or two sentences. Long stories bore examiners,this is why some brilliant students fail,even though they thought they have written all the answers in the world.
Kudos though

This is just basic concept of security IAAA

Identification - who you are - unique phone numbers

Authentication - providing credentials to prove your identity claims - PIN, Passwords etc

Authorisation - once you have authenticated, what can you you now do. What rights have you got?

Accountability - records of what you have done with rights provided so as not to deny doing it. Why your phone has phone call logs. Non repudiation

goestohell:
Ñairaland's problem is that important subjects like this rarely make it to the front page and when they do, the response is always slow and uninspiring.

Let lalasticlala post a thread showing Toke Makinwa wearing a see-through blouse and sit back see it go viral in 5 minutes.

Subjects like this rarely make it to front page because there is low demand for such subjects.

Seun is a business man, he knows that Tonto dike and toke makinwa topics are what majority of Maryland come for.

He doesn't want to be put out of business.


Same reason why Nigerian singers that sing sensible songs don't blow

Classic explanation. OP u too much. Please go and collect one Bottle of malt from that shop down the road. Tell her that I'll pay when I come back from work.

Sweet Story

Wonderful.

Nice