Hacker Newsnew | past | comments | ask | show | jobs | submitlogin

Indeed. But there are also delays that cause good feelings.

I still remember the POS in my previous employers cafeteria. It had something like 100-200ms delay in processing a contactless payment card. It felt like an order of magnitude faster than any grocery store (exact same POS device). It was always very satisfying to pay for lunch. By the time you brought the card to the reader it felt like it was already printing the receipt.

I always wonder how it was so fast and if it was just some random dev optimising some obscure edge case.



In South Africa I notice this difference all the time where the big supermarket chains seem to be near instantaneous while small stores are 10+ seconds.

I'm certain it's because the big store's card machines have a wired network connection to a router with a fibre connection, while most smaller shops just use card machines with integrated GPRS wireless modems as they even show feedback about connecting as you tap your card.

A stall vendor who I use somewhat regularly warned me one time that her card machine was down (I guess some kind of maintenance as it was earlyish on a Sunday morning) so would only be able to accept cash. I helped her put the card machine on a nearby shop's free WiFi and not only did it work around the problem, but it made card transactions going forward significantly faster.


May be your cafeteria was doing offline processing, while other were doing it online?

But even offline there are huge differences, say Visa / Mastercard EMV and Suicia's Felica in Japan, where the whole transaction finish in 150ms.

There were previously some work where they try to get it down to 50ms, I don't know if they are still working on it or has abandoned it.




Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: