Loading the GeldKarte
The GeldKarte chip can be loaded either at a bank counter, in a cash dispenser, or in specially designed self-service terminals which can be found in the entrance foyers of some banks. Some retailers have also installed loading terminals for the convenience of their customers. Loading an account-linked GeldKarte is done in precisely the same way as withdrawing money from a cash dispenser:
- Insert the card
- Select "Load"
- Type in PIN
- Select amount, and confirm.
The amount requested is now automatically transferred from the bank account to the microchip. Stand-alone cards can only be loaded against cash payment or other cards. No PIN is required for this. When a GeldKarte is loaded, the terminal connects with the loading centre responsible for the transaction in question. This centre is an important security feature in the GeldKarte system: it has the task of checking and authorizing the loading process. At the same time, the amount loaded is credited to a purse settlement account at the issuing bank. Details of the loading process are also passed to a transaction registration centre, which then adjusts the balance in the shadow account of the card number in question.
Payment
To make a payment, the card is inserted into a terminal at the checkout or into a slot in the vending machine. At the checkout, the customer must confirm the amount shown. This is not necessary when a vending machine is used. No PIN or signature is required. The amount payable is automatically deducted from the credit stored on the chip and credited to the retailer's chip which sits in the terminal. This is done offline, without the use of an authorization system. This keeps transaction costs to a minimum, and cuts down the time involved.
It is also possible to use GeldKarte for payments via the Internet. This has advantages for both the buyer and the seller: the buyer can pay simply and anonymously, and the seller has the guarantee that payment has actually been made – as with cash payments.
The settlement of payment transactions
Only when a payment transaction has been completed does the merchant's chip generate data on each payment, which it then transmits to the merchant terminal. It adds further data containing information specific to the merchant and terminal in question, before storing the full payment data record.
The merchant closes the till or the vending machine with a so-called reconciliation. The merchant chip card then generates a cumulative total from all the transaction data that have been stored. This total data record comprises and automatically encrypts all the individual transactions. Each total data record can be clearly identified by means of the identification number of the merchant chip and a serial number of the reconciliation.
Using these code numbers and the serial numbers of the individual transactions, the merchant transaction registration centre used by the merchant's bank can later check whether transactions have been submitted more than once. The payment amounts are credited to the merchant after he has submitted the individual transactions and the total data records to the merchant registration centre.
The card transaction registration centre then charges the value of the transactions conducted by the card holders to the settlement accounts of the banks that issued the cards. At the same time, payments made are deducted from the shadow account of the individual GeldKarte used. Since payments are not cleared individually, but only in the form of totals, it is not possible for the banks to "pry" into customer transactions. The diagram below shows more detail on the technical procedure used when payments are made with the GeldKarte.
Unloading the GeldKarte
Account-linked GeldKarte cards can be unloaded at loading terminals operated by the issuing bank. They can be unloaded at any time within three months of their date of expiry. Upon instruction from the loading centre, the credit on the card is cancelled and transferred back into the card account from the purse settlement account. No PIN is required for this, since the credit stored on the card is credited directly to the holder's current account. As is the case when a card is loaded from a current account, the terminal has a purely intermediary role when cards are unloaded online, acting as a connection between the account-linked card and the loading centre.
Technical equipment in bank branches
To participate in the GeldKarte system, banks must have the following hardware:
- Loading terminal:
The loading terminal can be installed either in the service area or the self-service area of the bank. Self-service machines installed at acceptance points are also operated by the bank. Most loading terminals also have an unloading function. At these terminals, only GeldKarte cards issued by the bank concerned can be unloaded. The credit must be transferred back to the holder's current account. Only the full amount of credit stored on the card can be unloaded. - Special function terminal:
These machines have the same functions as a loading terminal, but also offer additional services, e.g. card-loading against cash payment, or card problem solving (only operated by members of the bank’s staff). - Pocket card reader:
Compact and easy-to-use devices which can bei issued to clients. They show the current balance on the card as well as the last three loading transactions, and the last 15 payments. For an example, have a look in our GeldKarte- Shop! - Connection with the loading centre:
The loading terminals and special function terminals can be connected to a loading centre either with or without the support of a network operator. The technology used includes, for example, Datex-P and ISDN.