Lucian
ULTIMATE Member
Ok, this is both surprising and eye-opening, I always thought a SIM is just read-only memory.
news.ycombinator.com
"A SIM card is a full blown computer with its own CPU and memory.
Your carrier can upload and run arbitrary code without your consent or knowledge. They can do this at any time.
This means that your "phone" is actually three different computers running in concert - the actual phone itself (iOS or Android or Symbian), the baseband processor running the baseband code, and the SIM card."
Example hardware from the same link:
"Atmel AT90SC25672RU, 8-bit AVR, 256KB ROM, 72 KB EEPROM, 6 KB RAM, Between 20 & 30 MHz"
What is AT&T doing at 1111340002? | Hacker News
"A SIM card is a full blown computer with its own CPU and memory.
Your carrier can upload and run arbitrary code without your consent or knowledge. They can do this at any time.
This means that your "phone" is actually three different computers running in concert - the actual phone itself (iOS or Android or Symbian), the baseband processor running the baseband code, and the SIM card."
Example hardware from the same link:
"Atmel AT90SC25672RU, 8-bit AVR, 256KB ROM, 72 KB EEPROM, 6 KB RAM, Between 20 & 30 MHz"























