6.5. Other Payment Services on the Internet
Besides SET, there are other payment protocols being discussed, implemented, and tested. Among these, we briefly discuss the following: electronic checking, digital cash, and W3C's common markup for micropayment per-fee-links.
An electronic check is similar to a paper check but safer. As in SET, a customer needs a e-wallet to store information on the browser about the checking account. When the customer is ready to make a payment, an encrypted message is sent to the merchant's site. This message is encrypted with the merchant's public key and has the account number of the checking account encrypted with the customer's bank public key for added protection. The merchant verifies that the information in the electronic check (i.e., the amount) is correct and sends the electronic check to the bank to obtain funds. The e-wallet at the customer side keeps a log of all checks issued, similar to a checkbook register in the physical world.
| Year | Merchant | PG | Merchant | PG |
|---|---|---|---|---|
| (no ECC) | (no ECC) | (ECC) | (ECC) | |
| 1 | 8 | 8 | 3 | 3 |
| 2 | 7 | 7 | 3 | 3 |
| 3 | 6 | 4 | 2 | 2 |
| 4 | 5 | 4 | 2 | 1 |
| 5 | 4 | 3 | 1 | 1 |
Digital cash, or e-cash, is aimed at transactions that deal with small amounts of money, such as in providing access to publications or real-time information (e.g., stock quotes). In digital cash systems, users can store e-cash in their e-wallets. E-cash is generated by a bank and digitally stamped by it. The amount of e-cash is withdrawn from the customer account and sent to the customer e-wallet to be stored. To make a payment with e-cash, customers send the the right amount of e-cash to the merchant software, which sends it to the bank for verification and redemption [1].
The World Wide Web Consortium (W3C) has specified, as part of its electronic commerce activities, a system for micropayments [10]. The idea is that one may have to pay a fee to traverse certain links. W3C's specification has produced an extensible way to embed in a Web page all the information needed to initialize a micropayment. At the browser side, multiple e-wallets and payment systems may coexist and interact with the per-fee link handler.