I recently switched phone providers, replacing the SIM chip. Which got me wondering an old wonderment: what's inside? It's remarkable that the industry has standardized on a single form factor and pin out. But I'm curious, what is the separation of functions, between the chip and the surrounding device? How to characterize it as a black box, what exactly are the signals which flow across the pins? Do any of those pins carry analog waveforms? I figure this is a reasonable place to ask such a question - -- Rich
SIM chips
Started by ●September 14, 2023
Reply by ●September 14, 20232023-09-14
torsdag den 14. september 2023 kl. 19.58.07 UTC+2 skrev RichD:> I recently switched phone providers, replacing the SIM chip. > Which got me wondering an old wonderment: what's inside? > > It's remarkable that the industry has standardized on a > single form factor and pin out. But I'm curious, what > is the separation of functions, between the chip and the > surrounding device? How to characterize it as a black box, > what exactly are the signals which flow across the pins? > Do any of those pins carry analog waveforms? > > I figure this is a reasonable place to ask such a question -I wonder if maybe, just maybe, google will have an idea, .. https://en.wikipedia.org/wiki/SIM_card
Reply by ●September 17, 20232023-09-17
On Thursday, September 14, 2023 at 1:58:07 PM UTC-4, RichD wrote:> I recently switched phone providers, replacing the SIM chip. > Which got me wondering an old wonderment: what's inside? > > It's remarkable that the industry has standardized on a > single form factor and pin out. But I'm curious, what > is the separation of functions, between the chip and the > surrounding device? How to characterize it as a black box, > what exactly are the signals which flow across the pins? > Do any of those pins carry analog waveforms? > > I figure this is a reasonable place to ask such a question - > > -- > RichYou can buy a USB adapter, that comes with software to read the content.
Reply by ●September 17, 20232023-09-17
On 17/09/2023 15:43, Michael Terrell wrote:> On Thursday, September 14, 2023 at 1:58:07 PM UTC-4, RichD wrote: >> I recently switched phone providers, replacing the SIM chip. >> Which got me wondering an old wonderment: what's inside? >> >> It's remarkable that the industry has standardized on a >> single form factor and pin out. But I'm curious, what >> is the separation of functions, between the chip and the >> surrounding device? How to characterize it as a black box, >> what exactly are the signals which flow across the pins? >> Do any of those pins carry analog waveforms? >> >> I figure this is a reasonable place to ask such a question - >> >> -- >> Rich > You can buy a USB adapter, that comes with software to read the content.Modern mobile phones also offer eSIMs with no physical card at all. -- Martin Brown
Reply by ●September 22, 20232023-09-22
On September 17, Martin Brown wrote:> >> It's remarkable that the industry has standardized on a > >> single form factor and pin out. But I'm curious, what > >> is the separation of functions, between the chip and the > >> surrounding device? How to characterize it as a black box, > >> what exactly are the signals which flow across the pins? > >> Do any of those pins carry analog waveforms? > >> You can buy a USB adapter, that comes with software to read the content. > > Modern mobile phones also offer eSIMs with no physical card at all.A SIM chip can be replaced by software? I thought they had rf detectors inside, TDM, FDM, CDM... -- Rich
Reply by ●September 23, 20232023-09-23
fredag den 22. september 2023 kl. 22.47.14 UTC+2 skrev RichD:> On September 17, Martin Brown wrote: > > >> It's remarkable that the industry has standardized on a > > >> single form factor and pin out. But I'm curious, what > > >> is the separation of functions, between the chip and the > > >> surrounding device? How to characterize it as a black box, > > >> what exactly are the signals which flow across the pins? > > >> Do any of those pins carry analog waveforms? > > > >> You can buy a USB adapter, that comes with software to read the content. > > > > Modern mobile phones also offer eSIMs with no physical card at all. > A SIM chip can be replaced by software? I thought they had > rf detectors inside, TDM, FDM, CDM...no, it is only a bit of data to identify you on the network
Reply by ●September 23, 20232023-09-23
On September 23, Lasse Langwadt Christensen wrote:>> >> You can buy a USB adapter, that comes with software to read the content. > >>> Modern mobile phones also offer eSIMs with no physical card at all. > >> A SIM chip can be replaced by software? I thought they had >> rf detectors inside, TDM, FDM, CDM... > > no, it is only a bit of data to identify you on the networkI know Qualcomm is a big player. I thought their CDM devices are inside the SIM chips. What exactly are they selling then? -- Rich
Reply by ●September 24, 20232023-09-24
søndag den 24. september 2023 kl. 01.34.21 UTC+2 skrev RichD:> On September 23, Lasse Langwadt Christensen wrote: > >> >> You can buy a USB adapter, that comes with software to read the content. > > > >>> Modern mobile phones also offer eSIMs with no physical card at all. > > > >> A SIM chip can be replaced by software? I thought they had > >> rf detectors inside, TDM, FDM, CDM... > > > > no, it is only a bit of data to identify you on the network > I know Qualcomm is a big player. I thought their CDM devices are > inside the SIM chips.no, https://en.wikipedia.org/wiki/SIM_card> > What exactly are they selling then?The main chips that makes up the functionality of a cellphone the SIM card is only a bit of encrypted data to identify you on the network the phone doesn't need a SIM card to make calls, you can call 911/112 without a SIM card
