3 ms·
Interesting fact: the best card terminals, if they are connected to a phone line rather than the merchant's broadband internet connection, use a 1200-baud modem
by db48x 9y ago
Interesting fact: the best card terminals, if they are connected to a phone line rather than the merchant's broadband internet connection, use a 1200-baud modem. You would think that this would be slower, but the amount of data to transfer is relatively small. This means that the transaction time is dominated by time it takes to dial the modem and establish a connection rather than the time it takes to send the data. A 1200 baud modem takes much less time to negotiate a connection than a 56k modem, because it doesn't have to check the quality of the line as thoroughly. Reliability is better on noisy phone lines as well, and I'm sure they're cheaper. It's a win all around, but it's not something they mention on the spec sheet because it looks terrible.
Of course that has nothing to do with the chip-based authentication.
- justin66 9y agoIt's been 18 years since I was involved in that industry, but I remember it being more a decision to use 1200, 2400, or 9600 baud with most processors. I don't remember any that even offered the option to connect at 56k. I think there were a few processors with protocols that were chatty enough that the time spent negotiating 56k might have been worthwhile. I remember the Gensar and FDMS protocols mostly being sane but there were a couple others that were "hey look at this BBS software I adapted to be a credit card processor for some reason."
- aninhumer 9y agoSurely in a busy enough store it would be worth just keeping the connection open, at least during peak times?
- Mister_Snuggles 9y agoA lot of POS terminals in Canada just use Ethernet to connect to the payment processor. For stores that already have internet they just hook into that, but for those who don't one of the local ISPs even offered (they might still) a $5/mo cable modem package just for POS machines.