If you’re reading this newsletter, you probably know DFC as your friendly neighbourhood boutique IT and business solutions company. But perceptive readers are also aware that we sell barbecue sauces (developed from David’s legendary from-scratch recipe) too! Our sauce business has taken us all kinds of places; from barbecues to country fairs to the shelves of fabulous local grocers. But no matter how deeply involved we get in our side gig, our first love — technology — always finds a way in!
Most recently, I was struck by the powerful little gadget that is the Square credit card reader. This little reader plugs into a smartphone’s headphone jack, and, when paired with the proprietary app, processes in-person debit and credit orders when we’re out in the (sometimes literal) field.
I was intrigued by how this 21st Century doodad worked, so I dug a little deeper. Turns out, it’s distantly related to some very 1990s technology: the dial-up modem. When it detects a swiped credit card, the Square converts the information on the magnetic strip (owner, number, expiry, and CVV) to an UNHOLY sound, which it then sends through the headphone jack. This sound is “decoded” by the app back into a recognizable credit card number, and the transaction is completed.
“All credit card readers basically function this way, although their noise is much harder to eavesdrop in on compared to the Square reader since they aren’t hooked up to a headphone plug. The screeching of a dial-up modem also functions somewhat similarly, in that they transmit data via noise, then send it over phone lines. The initial noise when your modem attempted to connect is called a ‘handshake’ […] The modem had a little speaker to play the handshake, so that users would know if something went wrong, like a clueless parental figure picking up the phone in the other room when you were halfway through downloading a mislabeled bluegrass cover of ‘Gin and Juice.’”
If you’re intrigued, The Outline, quoted above, pointed me towards this handy primer that breaks down the language of a dial-up modem’s “conversation” with a personal computer. I knew that the screeches that greeted my attempts to get online in the last century served this purpose, but I was fascinated to learn such a discreet, speedy, and small bit of modern tech was based on this same principle. Much like natural evolution — if it ain’t broke, don’t fix it. Build on it!