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What happens when you swipe a credit card

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Re: What happens when you swipe a credit card

#161

Post by kevin_thibedeau »

GrinningFool wrote: post #49
coin wrote: post #4

> swipe your card Sadly swiping is being replaced by chipcard.

> Sadly swiping is being replaced by chipcard. I see this being downvoted, and I'm wondering if it's not simply just misinterpreted. Most places in the US I've used chip&pin, the process goes like this: - arrive at merchant, select goods, get total. - look for a sign that says chip is not enabled. - failing that, move assuredly towards the chip reader and keep an eye on the cashier to ensure he or she doesn't move to…

Even better are the terminals set up to use the chip for credit transactions but require a swipe for debit (after inserting the card and selecting debit). Truly a WTF moment when that happens.

Re: What happens when you swipe a credit card

#162

Post by joopxiv »

Depending on the category of the merchant, the network charges an interchange fee, the cost of which is split between the issuing bank (which takes most of the cut), the card association, and the acquiring bank.

This isn't entirely correct. The interchange is the part of the transaction fee that goes to the issuer. The card network gets a scheme fee, and the acquirer/processor charge a fee on top of that. If a merchant pays the same rate, regardless of what type of card is used, (credit/debit, consumer/business) then the processor or acquiring is basically rounding up.

Re: What happens when you swipe a credit card

#163

Post by criddell »

icebraining wrote: post #137
criddell wrote: post #115

Earlier quoted context omitted.

The data doesn't really end up with advertisers though, does it? I can't call up AMEX and ask for a list of all the places my member of Congress uses his card, can I?

You can't ask for individual data points; you ask for a segment of the population (eg. "musicians over 40 with children") and they'll return the data aggregated in bulk.

I don't think they will actually return the data though. I think it's the same as Facebook. You can target ads to a certain segment, but they won't actually tell you who is in that segment or what the actual data is.

Re: What happens when you swipe a credit card

#164

Post by avar »

digler999 wrote: post #88
leejo wrote: post #56

Earlier quoted context omitted.

> if you need more entropy then add another digit. That would break so much as most of the message formats and batch files use fixed width fields. It's probably the same for the databases underneath. Changing to alphanumerics sounds nice but the check digit algorithm would have to change from Luhn to Luhn mod n. More breaking changes. Banking systems are one of the ultimate forms of legacy, which is why most of the s…

> but the check digit algorithm would have to change or just get rid of it. It was a relic from 20+ years ago when networks and computers were 1/100th the speed they are today. Let them enter invalid numbers. Let the server return an error (as it already does)

The check digit gets used today by e.g. JavaScript in input forms to indicate a typo in the card number.

Re: What happens when you swipe a credit card

#165

Post by discreditable »

wheelerwj wrote: post #156
discreditable wrote: post #117

Earlier quoted context omitted.

I have a Final card. You have three options: 1. Use your real card number. I never do this. 2. Use a merchant-locked card number. I use this commonly for online pizza and other online shops I don't trust much. Once a merchant uses it, only that merchant can use it. 3. Use a one-time card. The number is used once and disabled. Good for one-off orders or skeezy purchases. Overall I've been pretty pleased. I think the i…

this is pretty solid actually, ill have to check it out. edit, i checked it out. so 1) its no open to sign ups, and 2) you have to have pretty stellar credit to even be considered. so that leaves out most people.

Dang, I didn't know about the signup thing. I hopped on when they had an open beta period. (Kinda weird to say that about financial services!)

Re: What happens when you swipe a credit card

#166

Post by koffiezet »

Cyph0n wrote: post #11

I'm kind of disappointed that you didn't go into the security features present in a typical credit card transaction. For example, you could describe the crypto protocols used to communicate with the gateway and/or card processor, what kind of data the stripe and chip contain and how it is used for authentication, etc. Another thing I find interesting is the anti-tamper features that are present in a standard credit c…

Not surprisingly, EEVblog gets many things wrong or expects wrong things in that video. But still, having done a lot of embedded work on POS terminals in the early 2000's, it was a bit strange to hear him get things so wrong since for me they were quite obvious (SAM slots etc). Usually he's better informed - but POS terminals are strange beasts, although these days it's all ARM and a normal Linux that's running on the main cpu...

Re: What happens when you swipe a credit card

#167

Post by dangerboysteve »

jonknee wrote: post #101
dangerboysteve wrote: post #99

I stopped reading after the first sentence "Ninety percent of Americans have used a credit card" which I find to be completely untrue and fabricated.

They're obviously talking about adults and I don't think that number is too far off, what would you put it at?

I realize, like most people, they were referring adults and a quick google search has the number pegged arround 72%.

http://www.creditcards.com/credit-card-news/ownership-statis...

Re: What happens when you swipe a credit card

#168

Post by arfrank »

wheelerwj wrote: post #156
discreditable wrote: post #117

Earlier quoted context omitted.

I have a Final card. You have three options: 1. Use your real card number. I never do this. 2. Use a merchant-locked card number. I use this commonly for online pizza and other online shops I don't trust much. Once a merchant uses it, only that merchant can use it. 3. Use a one-time card. The number is used once and disabled. Good for one-off orders or skeezy purchases. Overall I've been pretty pleased. I think the i…

this is pretty solid actually, ill have to check it out. edit, i checked it out. so 1) its no open to sign ups, and 2) you have to have pretty stellar credit to even be considered. so that leaves out most people.

Email me at aaron@getfinal.com and we can get you a code to apply :) We're working on broadening our underwriting criteria, but this is a complicated business overseen by an incredible amount of regulation, while also taking risk when we issue new lines of credit. Large banks throw around a lot of $ to make it work (a lot in this statement), but to start a new provider takes a lot of tactical decisions and iteration to grow in a safe and sustainable way.

Re: What happens when you swipe a credit card

#169

Post by arfrank »

discreditable wrote: post #117
nickpsecurity wrote: post #96

Earlier quoted context omitted.

The first part is basically what Final claims to be doing: https://getfinal.com/

I have a Final card. You have three options: 1. Use your real card number. I never do this. 2. Use a merchant-locked card number. I use this commonly for online pizza and other online shops I don't trust much. Once a merchant uses it, only that merchant can use it. 3. Use a one-time card. The number is used once and disabled. Good for one-off orders or skeezy purchases. Overall I've been pretty pleased. I think the i…

Email me @ aaron@getfinal.com I'd love to hear more, if you don't mind. We encourage people to use the physical card and just treat it as disposable if it ever gets skimmed/breached/stolen/lost. We made sure it impacts none of your other relationships :)

Re: What happens when you swipe a credit card

#170

Post by arfrank »

discreditable wrote: post #165
wheelerwj wrote: post #156

Earlier quoted context omitted.

this is pretty solid actually, ill have to check it out. edit, i checked it out. so 1) its no open to sign ups, and 2) you have to have pretty stellar credit to even be considered. so that leaves out most people.

Dang, I didn't know about the signup thing. I hopped on when they had an open beta period. (Kinda weird to say that about financial services!)

There are a tons of reasons to keep our signups closed for now. One non-obvious reason to most people is that it costs us money to lend out money to customers. Theres a ton of others we're working on solving in parallel too
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