Simple PrePay/Checkout System Using MagCards?

An Anonymous Coward asks: "I help at a small youth club that has various events on different nights. For awhile now we have had a snack bar of sorts and have been thinking of developing a pre-paid system. We have access to plenty of computers and magnetic card readers (wit blank cards) but any ideas on the software? Also, would there be any way of also using this to keep track of a CD sign-out system?"

Comments

Extra Layer of securiy req'd

[vreeker]

As suggested above the security of mag cards are quite trivial. However if you kept a record of what *should* be on the cards on a database of some kind any attempt to use a modified card could be spottted and dealt with.

This somewhat stupifies the usage of the mag cards as you could just as easily use a barcoded card to track the users and keep all information local.

CD borrowing system could work just like any library system now. Each user has a barcoded card (easily could be a mag card) that has a user id of some sort. Then the server keeps track of the rest. An added bonus to using the barcode is people could "log-in" from home and check account status. With a mag card the users would need an additional user id printed on the card. (Or assigned one in the application process).

Just my two clams from above the border.

Mag cards...

[shumacher]

A couple of security suggestions:
1) Avoid sequential numbering.
2) The Mag stripe should have information that's not printed on the card.
3) Printed information on the card should be verified against data from the swipe.
4) Mag card numbers should be independent of any specific user information.

iButton

[JediTrainer]

Try the iButton. It's a Java-based little button that can be placed on a keychain (or ring, or watch, or wallet). I imagine they're probably simple enough to program with, and probably difficult to hack. I believe they all come with a unique identifier that can be accessed which cannot be overwritten, unlike with a mag-card which can easily be copied and forged.

Should be relatively trivial to write a program to interface with a database every time it's touched to your terminal, depending on what sort of transaction you wish to take place.