How Do SIM Cards Work?
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- Опубликовано: 2 авг 2016
- SIM cards allow you to make calls and use data on your mobile network, but how do they work, and how can they restrict what you can do with your phone?
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Наука
luke:
"vine and snapchats and other stuff the kids are doing"
*TINDER LOGO*
😂
Was just about to comment that 🤣
Lmao
Kids, tinder *holdup*
let's be honest, a bunch of kids are probably on tinder.
Two things that didn't make it to 2020: Vine and Luke without a beard.
Tik Tok did
Robbie Cresswell and Jayden Chang. The creator of Vine created a new app called Byte. So if you want to download that then you can do that. It’s basically the same domain as vine but replace vine with byte.
and the windows phone
And windows phone
And windows phone
Yo it’s 2024 and I’m here
Same
Indeed it is
Oh wow. R u really?? 😅
Uh huh
Same
although I consider myself to be a tech/network geek, it was great to have that explanation put simply. definitely would like to see more mobile network/cell network talk. thanks Luke.
now do a video explaining how gsm carrier locking works
It's illegal in Canada now
Damn that's gonna be hard... Anyways I only learnt about such a thing in this video
As far I know that carrier lock using cdma while unlocked using gsm
@@thekcorner424
Jk
It's not a big deal. A password locks other carriers from accessing your phone so that password can be retreived from your primary carrier or generated.
>Stuff that the kids doing
>Tinder logo
(͡° ͜ʖ ͡°)
I made it 69 likes from 68
Vine
(. )
.).)
-Pornhub into-
The ability store contacts on a SIM card is actually really useful when switching phones. It doesn't work all the time though
i don't think you can access them at all on an iPhone which is pretty awful. I like to save key contacts on the sim as well, ya know 'just in case'. I think you can also save messages on them using the messages app from samsung, dunno what that's about. anyway, abracadabra, you are now 5 years older
@@danimayb it's an ability that isn't there anymore, even though the SIM still has it. more importantly, your carrier puts all their important contact numbers on the SIM, probably most used being the remaining data check.
and it would be super useful in an emergency when you put your most important contacts on the SIM, that way when your phone is dead you just borrow someone else's or buy a flip phone from Kmart and pop that bad boy in
Edit: also, apple does not make it easy to come over from android. damn, the only way I was able to access and manage my fucking apple notes was when I moved to android and used samsung smart switch, still can't get the notes off my mac though
The worst part about Sim locking is that you need to get through it first before you can root. And this can be a problem if there isn't someone out there that has successfully opened a passage through the ADB bootloader.
And while a lot of contract companies are leaving the SIM behind, pay phone companies have started to adopt the SIM to stop people from removing sponsored applications.
Rooting can be wildly different. See the SM-N900V scene.
i thought my ad-blocker was on :P
Speaking of ad-blockers, tunnelbear!
Andrew Tran (fuck)
+Andrew Tran (shit)
Speaking of tunnelbear, SquareSpace!
+Throne Slingshot shit this is getting out of hand, but do you want that to be pink, Dbrand!
Why is the SIM card so much bigger than the actual chip?
Would't it been easier in the first place to manufacter smaller slots?
Why did we have to go in "steps"?
wanna know that to
Older ones had much bigger guts, and for the sake of compatibility phone makers have been slow to reduce the size of the slots.
+TiagoTiago The original full size Sim was credit card sized.
+Okaro X
Depending on the carrier, they still come attached to a credit card sized adapter (you can break it off if your phone doesn't got a credit card sized slot).
SIMs were originally the size of a credit card.
Then they wend down to the mini which was what we used in the 90s, then the micro came out which was used in same smart phones, then nano was what was the new thing.
Technically what you're describing is not SIM locking but netlocking. SIM locking would mean that the SIM card can only be used on a particular phone.
“Vines” not anymore
"iPhone, Galaxy or Windows Phone"
the ignorant over-simplifying, it's... it's killing me.
Those are the only phones that are relevant and you know it so quit crying about no name Chinese brands.
+MSWindowsinside Windows phone are about as useful as a flip phone.
Hey what do you have against flip phones
iOS, Android or Windows Phone.
They would rather take shots at other operating systems...
Also... galaxy? Come on. That's not all Android phones.
+Aseril HTC, Motorola and Sony are not chinese. And Xiaomi is amazing, and second place on best price/performance in the world... I read that somewhere.
I am so goddamn butthurt about this holy fuck.
***** Yes, the nokia lumia 365 from a friend and windows OS is absolute crap, useless in every sense of the word.
How about one on white balance? Clearly "someone" could learn from it...
:P
I'm pretty sure that's a green screen...
SAVAGE
+Dan Honey lol yeah
maybe one on how tans occur too
I had to rewind the first thirty seconds because I couldn't get over how he wore a v-neck with a spray tan like that
This was a really nice video explaining the science of sum cards.. Love the animation by the way.
I remember back in like the early to mid 90s in Canada the the Bell company used to use a network called CDMA (Code Division Multiple Access) and the Rogers company which used to be called Cantel AT&T and then later was called Rogers AT&T before becoming just Rogers Wireless used to use a network called TDMA (Time Division Multiple Access) neither of which required SIM cards in fact on most of those phones there wasn't even a space for a SIM card to go into but nowadays both companies are pretty much GSM now
But Maxis got dissolved by EA...
They actually still have the part of Maxis that develops the Sims.
but it'll never be the same :(
Along with over 10 other companies. EA only buys companies to kill them.
I thought that was only part of Maxis, the part that made the last SimCity game. I thought the team that make the Sims was fine.
Yoooooooooo
Lol I'm using lte
I knew this video was old when he said vine
It's meme now😂
0:23 I sure hope the kids aren't doing tinder.
Vines and snapchats, and...
RIP VINE 🙏 ⚰ 🙏
I think that you guys should do a video on GSM Vs. CDMA networks please! I work for Verizon and I still have trouble wrapping my head around it
Very informative video, I learned a lot about tech last few years but didn't know much about sim cards, how they function, save contacts, etc... Also if unlocking your sim is legal now why do carriers still make phones with locks?
They normally lock the SIM to prevent theft until the device is paid for... Yes you could "hack" the phone and unlock it, its not the norm.
Thank you that was very informational. I learned something new
Would have been great if you also went into the difference between USIM and SIM. Also get into why Verizon SIMs can't be simply swapped between phones, and must register the SIM with the new phone. Metro (Which is no longer CDMA) and Sprint do this too. (I know they are CDMA, but need to know why swapping SIMs isn't easier.
Yeah, me too
Five years later haha
this made me so mad when I switched to t mobile after sprint got bought I didn't know how easy it was to swap phones on GSM!
Can you do a History of Linus Media Group fast as possible? Would be awsesome :)
One thing people didn’t mention: Luke is back!! Glad to see you again on TechQuickie!
This Video was very informative. Thank you.
Ting really missed out on a good sponsorship opportunity here.
harambe died in real life and died as a meme
who is harambe?
+shreenidhi deshpande SHOW SOME RESPECT FOR HARAMBE
All memes go to heaven eventually, just like Harambe.
Harambee For President
#dixoutforharambe
on some sim card slots you can put in a smaller sim card as long as it is lined up right
You can also buy plastic adapters
Thanks for making this video and posting it onto RUclips.
What is wrong with the colours in these videos? I get that they're using green screen but Luke's head and arms look yellow compared to his chest. I thought they'd have sorted the lighting by now.
It's a tan lol
farmer's tan
It's a tan. Look at the undersides of his arms whenever they show. IOW: Luke stands proudly and majestically gazing at the sun all day.
+SGM 26 Time for you to buy a new computer \ phone or what ever device you're using!
Video looks absolutely fine on my end!!!
No thank you needed, you're welcome!
SGM 26 it's call tan.
3:43 hey thats the girl from that meme with the unfaithful boyfriend
didn't appreciate the ad for square space (I pay for RUclips ad-free premium membership, so I just forwarded thru), but your sim card info was a big help.
thank you, great video :)
in the UK the carrier legally has to offer unlocking at the end of your initial contract for a "reasonable" fee (anywhere from £8 to £25 in practice).
Lol in Germany it's free after a 24 months contract has ended, also most ISPs do not use SIM locks anymore.
@@thebamplayer to be pedantic:
no "ISP" uses SIM locks. SIM locks are used by telcos to lock a phone to a particular phone network (ie voice calls, texts, and internet). An ISP is a firm that provides internet service as it's main or only trade, not a phone seller. The clue is in the initials: internet service provider.
OK the two roles often overlap these days but they are still different.
@@trueriver1950 I meant the phones you get from an ISP with discounts in a contract
@@thebamplayer so did I. If it's a contract for phone service -- or that includes phone service -- then it's a Telco not an ISP.
Internet is part of telecommunications, not the other way round.
SIM cards are much more complicated than this. They contain a very small CPU and RAM in order to do authentication and other calculations. They don't just store information, they process it in real-time to provide information. Most can also run Java code.
They're essentially small computers.
All this on a tiny meltable card
ty for the information techquickie
This channel is very very informative useful and meaningful
2:10 good example of key encryption =)
Last time I was this late, my boss told me to clean out my office and get out.
Just kidding. I don't have have a job remotely great enough to have an office.. or a job at all.. Guess it's time to crack open that bottle of bleach.
♥☻
Chug-a-lug.
Yeah, definitely time. Hope you had a good life.
don't worry man life doesn't get better
I have just shorted 240V AC :c
This episode reminds me of fast lane daily. ...I missed that show, thanx for the reminder
what about a video on the inner workings of the hardware used at the cell tower :) and network infrastructure ?
Vine, Windows phone, macro sim card..
This video is a piece of history
As someone who works with building the back end systems involved in this I do think you oversimplified it a bit. You only talked about the IMSI, but the IMEI and MSISDN are also important.
THANKS, Been wondering this ever since my first phone in 2015
Thank you for this video
A few questions:
- Are SIM cards any different in Japan, considering things like i-mode and the abundance of flip-phones? Or is it merely that i-αppli uses the SIM card differently (for example, paid-content licence verification)? Or both?
- Do service providers have policies against frequent hot-swapping of SIM cards? I'm on giffgaff (which runs on the O2 network), and due to a design flaw of my BlackBerry KEYone, I can't remove/switch microSD cards without also removing the SIM card, booting me back to the lock screen and sending Android into a bit of a frenzy. Would I get in trouble for that?
- Are there any "SIM card explorer" applications for Windows, Windows Mobile (6.5 or below), BlackBerry 7.1 or Android, that can browse the SIM card's memory as if it were another memory card? I want to be sure of exactly _what's_ hidden on that thing, and also want a more 'direct, down-to-earth, file-manager-like' way of mirroring contacts and texts on it.
- Do some SIM cards have more memory than others? So I could hypothetically transfer _all_ of my contacts and texts onto, say, a Windows Mobile 2003 device, or a cute Japanese flip-phone? (Last time I exported my texts and call logs into XML format, they were 722 KB total.)
- Are there any Android games that make creative use of the SIM card? Like, maybe using it in a gameplay mechanic, or for identification in leaderboards, or something? (Doesn't matter how old the game is; even if it's as old as Android Cupcake, I'd be eager to see it!)
Read this, but unfortunately, I don't have an answer. Still commenting, just to let know, yes, I've read this.
I recently read the i-mode service will be terminated in 2026 due to the rise in 4G/5G use.
@@prizegotti IKR? Shame they couldn't absorb it into 3G (and above), or implement support for it into iOS/Android, or something. (Maybe it's too proprietary, both technically and legally.)
One of those questions I can answer: yes some SIM cards do have more memory than others. In general if you ask your provider for a new SIM after a few years you will get more memory -- it's not so much a network based difference as one based on year of manufacture.
You mentioned you are on giffgaff: if your existing SIM is a few years old then ask for a SIM "for a friend" then when it comes do a "SIM swap". That way you lose service for only an hour or so. By cancelling your old SIM first you lose service for a few days.
@@BenM64 no it's not so much a proprietary thing -- after all there were/are more i-mode sites that were "unofficial" than were ever on the NTT official network.
It's more that now we have full internet service on any smartphone, there is no niche for i-mode and so, like WAP, it's become obsolete. Any site that wants to continue in use has a few years to migrate too the mainstream internet.
It does mean that buttons on old phones will no longer work because there is no service there: that already happens on 2G WAP phones: mine can still make calls but none of the WAP services work any more. It reports that there is "no internet" but what it really means is that there is no WAP service to connect to.
In my country, it is illegal for cell couriers to "sim-lock" your phone.
This is how I learned about unlocked and SIM cards thax Luke
cool geeky stuff, my head still spinning
All this time I thought SIM stands for SMART IDENTIFICATION MEMORY
thumbs down for that abrupt jump to that embedded advertisement that my adblocker is powerless against.
Did you know content creators need to make money?
Well explained!
Have you guys done videos on MIFI devices and how they work, as well as how the Sim cards work with them?
You need to eat less carrots Luke. They change your skin color.
Or you could just instruct your LTT minions to calibrate their equipment correctly.
It is a fake tan for a future super fun video. They talked about it in last weeks WAN show. Linus looks like it too in their last few videos.
+Mr Merlin I think they just wanted some Donald Trump cosplay.
Mr Merlin still way too orange. They need to use a color calibration sheet/card to set the white balance.
It's a tan, but yeah the color seems off.
Linus owns ltt not luke
This is not completely correct. The authentication key is never sent over the network. It only works with said random number operations. It's called Challenge Response Authentication.
Correct. In fact the authentication keys are stored locally in both the SIM card and the HLR. It is not calculated in real time.
The Thumbnail made me not sleeping because my phone was there
Please provide more information on gsm and cdma differentiation.
looking forward to it..
almost got me Rage quitting when he said Galaxy instead of Android.
now im a bit sad because he oversimplificated what a SIM card does.
Which phone was in the video?
Wasn't it a galaxy... you dumbass
Kojo K yeah. But galaxy phones run on android. He got mad? Because the guy in the video is referring to the galaxy phones like there an os, which they aren’t, they run android.
GRANDDAD maybe he ment something similar to it
@@kojok4667 you're dumbass
I see Mexico did you a favor with that farmers tan, Luke.
1:34 as you turn on your phone. As I literally turn on a phone that I cut a SIM card to fit into.
The description of a "SIM lock" is incorrect. The SIM Lock exists as a voluntary PIN that the user picks to make it so that if someone finds the SIM card, they cannot call, text, or use data without knowing your PIN. That's useful if you lose your phone and haven't called your cell provider to kill the SIM, yet. It is like using an Android or iOS PIN lock screen, except this lock is on the SIM, itself, so they can't even move the SIM into another phone to get around the PIN.
The lock you are describing is the Master Subsidy Lock or MSL. It resides in the DEVICE (not the SIM) and prevents you from using your phone with a competitor as a way of guaranteeing you become that carrier's customer in order to recover the subsidy cost they paid to bring you a cheaper device. In other words, they paid for some of your phone, so you owe it to them to use their service.
Last time I was this early, I didn't have a joke.
I still don't.
It's been 3 yrs for the god sake.
0:56 i've got actually one of these ...
1:24
Actually it's closer to 8.4 quintillion (not 9.2) because it can go into the negatives but I'm not sure if negative numbers are used for this kind of stuff
there is a slot more involved in a sim card, they are actually quite slow but fully functional mini computers. the user access side is a bit restricted, but they are quite advanced things these days.
Yes, the 18 quintillion unique numbers a 64 bit integer can store are indeed bigger than 9 quitillion. but you got the signed vs unsigned wrong. Sim cards use unsigned 64 bit integers, the number you quoted is only for SIGNED 64 bit integers. for a tech firm, you sure do get a lot of things very slightly wrong.
DJHenjin right because he should know every single thing related to tech perfectly and be a master in all subjects
Doesn’t make a lot of difference in practice so who cares?
No
2:17
That's my school calculator!
👍
Nobody:
Techquikie: SQUARESPACE
It was only illegal in the US to unlock your own phone for a brief period (I think it was a month or two) and what made it illegal was a librarian of congress, not an actual lawmaker but then the real lawmakers made it legal again pretty quick.
so I can go to t-mobile (example) get an iPhone 7 and unlock it legally ?
BE LS yes. But if you want a reduced price on it they probably wouldn't let you have it without a contract, which would have huge fees if you break it, without a contract you might aswell buy an unlocked one from online probably get it cheaper too
t-mobile is an unlocked carrier without sim locking, you buy phones there at full price, verizon atnt and i think sprint are totally different stories. but, carries in the us HAVE to unlock your phone if you request it when your contracts ends, thanks to obama.
Why not? Who will "lock it". Your operator or "Carrier" can and will lock you if you do not pay your bills. They can block you from using a phone that has been stolen. If you have a copy of another phone, your carrier may identify it to be a copy - someone else has the same IMEI number, and consider your copy as a stolen one. It should be impossible to sell copies, every phone has a unique IMEI that identifies manufacturer, and sequence.
Not really how a SIM work... More like what it is, why it's named a SIM and what a SIM do... But certainly not how the card works technically... For me it became clickbait in that way...
It's like a key can't do anying with out it
@@spikes7846
I know these comments are already rather old, but maybe other people still read them.
So, I remember a great talk about smart cards in general, though I can't find that one anymore. However I managed to find a few other ones.
In particular "SIM card technology from A-Z" from 36c3, watchable here. media.ccc.de/v/36c3-10737-sim_card_technology_from_a-z
And then there's another c3 smart card talk that references other smart card talks in one of the first slides, here: media.ccc.de/v/35c3-9346-in_soviet_russia_smart_card_hacks_you#t=91
Wow. I'am learning a lot
The outdated references in this are so freaking gold
RIP Vine🙏
WP MASTER RACE!!!!
very informative
The square space ad came out the blue i think i like it
Did you really just refer to an Android phone as a "Galaxy"?! SHAME!!
Bc it was a Galaxy.....dumbass lol
Dumbo. See the picture again
Jerry Pineda A Galaxy is an android phone but not all android phones are Galaxy
Dumbo. Jumbo?
Massos Mumbo Jumbo fan? :D
you know EA owns SIMS now not Maxis
Maxis never owned the Sims.
Maxis develops sims, and EA bought Maxis before making the sims
Almost Rainbow 😃
Maxis was the original creator of the Sims, before that got passed onto EA.
@techquickie, please go into detail about service contracts. I work in telecom and nothing pisses me off more than when someone comes in to upgrade when their contract is only 1yr old and say, "Well I paid full price for this phone last year, why do I have to pay this contract out to get a new phone?!??" To which I respond, you paid a subsidized amount on that phone, not the full cost.
i haven't watched in, like, 1 year and 3 months, so i didn't know that new guy was here.
I really hope you guys will correct this because I know for sure my LG has a sim-card to, and it does not fall under the following category's iPhone, Galaxy or Windows Phone. The past time I get the idea that LTT isn't for the real geeks, but more for the mainstream market. It is because of the simple "flaws" like this, it feels like you guys throw a few names together to sound modern and stuff.
By Galaxy he meant Android. An LG is an ANDROID.
Windows Phone FTW
I like the cell phone stuff!
Watching Techquickie at 2x speed. Techquickier
Windows phone is actually great...
I have and love Windows Phone. Problem?
wanna fight 😂
Lol
We used to call it Super USer Privilege on touch phones back in 2010 ish when one gained fuill access. IT was seen as no different than just doing whatever with ouyr own Desktop or Laptop PC. Made perfect sense, and I still collect sim crds, for the one thing this dude forgot to mention...THEY ARE GOLD! lol
64-bit numbers can store 2^64 unique numbers. Thats 1.8e19 no 9.2e18 as stated in the video. Were you thinking *signed* 64-bit numbers?
Can I go to Walmart and buy one
Yes you can it's all depends on which Carrier you want.
Windows 10 mobile for life!!!
Holy heck thought Luke was back at LTT. 🤣
I would appreciate if you could inform us on how SIM cards fail and why you should get a new SIM-card every now and then because of newer versions etc.
50% "explanation" - the rest is an ad for some hosting BS.
Well if it’s sponsored they have to do that they have to have a ad for it but true it didn’t have to be half
it wasn’t half. it was 1 minute
you mispronounced "Android"
thank you . good show. where do you buy your data online for a computer offshore on some oil rigs in the north sea ???and do you need any Sim cards for it ??? yes or no
This would be a great video to show to someone who was frozen in time for the past 20 years