alright, all of a sudden got thinking about this.
whats the deal with magnetic swipe cards, how secure are they?
to the best of my knowlage they function by haveing magnetic bands in the strip that either create induction in a wire or do not. that leads me to belive that they are probobly binary numbers.
first question: how many numbers? does it vary? a magnetic strip contains a __=bit number
second question: even if its 16 bit (my totally baseless guess) thats only 65535 numbers.
that sounds like alot… but really that means I should be pretty likely to be able to open my dorm with my visa card. (10,000 working student cards, so a few diffrent cards and I got reasonable odds to be able to unlock my door)
more so, there shouldn’t be a real way to tell if your flipping the card backwards and running a number in reverse… doubleing the trys on each card.
mabey I am wrong and the magnetic strip is analog and 10 digits or its 64 bit or I totally misunderstand everything. but it makes me wonder, could I theroreticly open a locked key carded room with a credit card? especially on a campus where there are 10,000+ people with cards with numbers that are “right guesses”