u/TimmBombadil

Sure there were zip zaps (knuckle busters) for getting the card data, but then how was this data actually sent to the processor to the acquiring and issuing bank? Also, when did the payment processors start being the ones to issue the cards?

And how would this have worked before payment networks developed? And how did this process change after the payment networks were established? Im guessing that NDC would be limited to processing payments for banks that had their own computer systems set up for this.