# wave and go credit cards
**URL:** https://boards.straightdope.com/t/wave-and-go-credit-cards/391076
**Category:** Factual Questions
**Created:** [February 6, 2007, 3:35pm UTC](https://boards.straightdope.com/t/wave-and-go-credit-cards/391076 "2007-02-06T15:35:29Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@According\_to\_Pliny](https://boards.straightdope.com/u/According_to_Pliny)
#### Post date: [February 6, 2007, 3:35pm UTC](https://boards.straightdope.com/t/wave-and-go-credit-cards/391076/1 "2007-02-06T15:35:29Z")
I’ve seen the ads but forget the term. They show someone in a coffee shop or quicky mart that just waves his card over the terminal to pay for stuff.
How does that work?
How does it know who’s card is paying for what?
How close do you have to be to make it work?
I’ve used wave and go cards to open locks on doors, any you can sometimes keep the card in your pocket and just turn toward the sensor.
---
### Author:  [@TheLoadedDog](https://boards.straightdope.com/u/TheLoadedDog)
#### Post date: [February 6, 2007, 3:43pm UTC](https://boards.straightdope.com/t/wave-and-go-credit-cards/391076/2 "2007-02-06T15:43:04Z")
Sure it’s a credit card?
Generally, my experience with these things is “treat 'em as cash. Lose it, and… well… lose it.” Generally, “wave and go” cards seem to be limited stored value cards. Some credit card companies (Visa springs to mind) offer debit cards which act as credit cards, so maybe it’s something like that.
The other possibility is that Joe Richguy with his gold credit card can use this function, but on an entirely different credit limit to his main one (how many coffees can a pickpocket drink in a day?), and is expected to telephone and cancel the card if it’s lost or stolen.
All the above is just a WAG though. I’m curious myself.
---
### Author:  [@treis](https://boards.straightdope.com/u/treis)
#### Post date: [February 6, 2007, 4:07pm UTC](https://boards.straightdope.com/t/wave-and-go-credit-cards/391076/3 "2007-02-06T16:07:23Z")
[QUOTE=According to Pliny]
How does that work?
[/quote]
RFID tag. Basically the reader puts out a radio frequency that powers a tiny circuit in the card which sends out your card’s information when the card is moved near the reader. [RFID tags](http://en.wikipedia.org/wiki/RFID)
[QUOTE=According to Pliny]
How does it know who’s card is paying for what?
[/quote]
The same way the card machine knows when you swipe your card now. It’s keyed in by the register, or automatically done. It charges whoever swipes their card near the reader.
[QUOTE=According to Pliny]
How close do you have to be to make it work?
[/quote]
Probably depends on the specific reader/card, but the Speedpass at Mobil generally needed to be within an inch or less of the reader.
---
### Author:  [@desdinova](https://boards.straightdope.com/u/desdinova)
#### Post date: [February 6, 2007, 5:16pm UTC](https://boards.straightdope.com/t/wave-and-go-credit-cards/391076/4 "2007-02-06T17:16:24Z")
> **[Visa, a trusted leader in digital payments](https://usa.visa.com/)**
>
> Visa is a trusted world leader in digital payment technology that connects and enables individuals, businesses, and economies to thrive.
> **[Mastercard - A Global Technology Company in The Payments Industry](https://www.mastercard.us/en-us.html)**
>
> We connect and power an inclusive, digital economy that benefits people, businesses & governments worldwide by making transactions safe, simple & accessible.
These links may be helpful to you. I don’t know if Discover or American Express have anything similar, but these are the RFID enabled cards offered by Visa and MasterCard.
---
### Author:  [@amarone](https://boards.straightdope.com/u/amarone)
#### Post date: [February 6, 2007, 9:00pm UTC](https://boards.straightdope.com/t/wave-and-go-credit-cards/391076/5 "2007-02-06T21:00:38Z")
[QUOTE=desdinova]
I don’t know if Discover or American Express have anything similar, but these are the RFID enabled cards offered by Visa and MasterCard.
[/QUOTE]
American Express Blue has RFID.
---
### Author:  [@Duckster](https://boards.straightdope.com/u/Duckster)
#### Post date: [February 6, 2007, 9:01pm UTC](https://boards.straightdope.com/t/wave-and-go-credit-cards/391076/6 "2007-02-06T21:01:20Z")
\
> [@](#):
>
> Accusations that RFID-based contactless credit cards can be easily read by thieves are nothing new, but this time, a group of scientists at the Univ. of Mass. has gone quite far to try and prove it.
>
> The group—calling itself the [RFID Consortium for Security and Privacy](http://www.rfid-cusp.org/) --is a group of computer scientists from the University of Massachusetts at Amherst, RSA Laboratories and Innealta with some non-traditional partners, including the San Francisco Bay Area Rapid Transit District (BART), the MIT Auto-ID Labs and the Programme for Advanced Contactless Technology (PROACT) at Graz University of Technology, Austria. The National Science Foundation funds much of the research, according to the group’s Web site.
>
> The group tested about 20 samples from various contactless credit cards and concluded that “the cardholder’s name and often credit card number and expiration are leaked in plaintext to unauthenticated readers” and “our homemade device costing around $150 effectively clones one type of skimmed cards.” Perhaps of greatest concern is the report’s conclusion that “RFID-enabled credit cards are susceptible in various degrees to a range of other traditional RFID attacks such as skimming and relaying.”
Source: [http://storefrontbacktalk.com/story/102906contactless.php](http://storefrontbacktalk.com/story/102906contactless.php)
\
Assuming the above to be accurate, one must balance their need for _convenience_ against a desire of security for personal information. My life doesn’t run so fast that such a convenience would ever outweigh my desire to protect against identity theft.