Four authentication modes of apg8205 – ACS APG8205 OTP Generator User Manual
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APG8205 – User Manual
Version 1.00
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3.0. Four Authentication Modes of APG8205
APG8205 has four authentication modes, respectively the Identify, Respond, Sign and Advanced 
Sign modes. During real transaction, cardholder selects the mode to be executed, which is usually 
instructed by the authentication form on the Internet. (e.g., ‘Insert your payment card and select the 
Identify mode on your personal card reader to log on your bank account’). 
● Identify mode - This mode can be used where one-time passwords are required. No
challenge, amount, or currency data is needed when using the APG8205. It may be used to 
generate the one-time password for e-banking login. 
● Sign mode - This mode provides a cardholder authentication function. It requires the
cardholder to input a challenge value (a set of decimal number of up to eight digits, usually 
provided by the Online authentication form), and, depending on the configuration of the card 
in use, the transaction amount and/or currency. It allows issuers to have the option to sign a 
challenge value for services that involve amount and currency, like in an e-commerce 
application. 
● Respond mode - This mode can be used to implement challenge-response authentication.
This mode functions in exactly the same way as Sign mode, but it doesn’t require the input of 
currency and amount values. It allows issuers to have the option to sign a challenge value for 
services that do not involve amount and currency. For example, logging in an online banking 
account. 
● Advanced Sign mode - This mode connects the CAP token more closely with a specific
transaction and can be used for signing a particular payment. It requires the cardholder to 
input the transaction data (e.g., the account number of person you are paying) into the card 
reader, which may be supplied to the cardholder on the Internet authentication form, or by the 
cardholder on the submitted form. The purpose of this mode is to obtain explicit cardholder 
approval of the transaction data. 
