Lesson 18 Electronic Payment Systems. Overview. Data Transaction Systems Securing the Transaction Real World Examples. Data Transaction Systems. Stored Account Systems Modeled after existing electronic payment systems such as credit/debit card transactions
Instantaneous (no approval needed)
Potentially Anonymous (traceability hard)
Supports low-value payment
Secret key from one can be used for many
Secret key extraction makes counterfeit money indistinguishable for E-Cash
SVPS must strike balance between privacy and tracking illicit activitySVPS Pros/Cons
Cents = count + digital signature
$ = count + digital signature
5$ = count + digital signature
Token value is sum of all
Basic unit = 1 cent
Token cntr = 10000
Token value = $100.00
The Little Yellow Lock = Warm Fuzzy
3. Invoice Sent
5. Send Payment Info
6a. Strip Order
6b. Digitally Sign
4a. Select Cybercash Pay
button in browser
4b. Select Credit card from
4c. Encrypt payment
info with CyberCash Public Key
4d. Digitally Sign Payment
BANKCYBERCASH IN ACTION
1.The customer opens an account with a
2. An issuing authority, like a bank, issues a
digital certificate authenticating a customer.
3. Other third-party merchants also receive
their digital certificate when they open their
4. The customer places an order.
5. Customer verifies the merchant’s digital
6. Customer sends encrypted purchase details.
7. When the merchant receives the order, the
customer’s own digital certificate is checked
for authenticity as well.
8. The merchant then returns its own certificate, order details, customer payment information, and the bank’s digital certificate back to the bank to be used to authenticate the transaction.
9. The bank will then verify the merchant certificate
and order information.
10. The bank will digitally sign and return an
authorization back to the merchant.
11. When these transactions are finished, the order is
9. Bank digitally
signs & sends auth
BANKSET IN ACTION
4. Place Order
5. Merchant Certificate Sent
6. Send encrypted purchase details w/ Certificate
2. Buyer Opens Acct
3. Buyer receives
7. Sends order to Bank w/
customer payment info &
10. ORDER COMPLETE
8. Bank verifies merchant
certificate and order info