This paper describes TAPI, an offline scheme intended for general Internet-based micropayments. TAPI, which extends and combines
concepts from the KeyNote Microchecks and OTPCoins architectures, encodes risk management rules in bank-issued users’ credentials which are in turn used to acquire
small-valued payment tokens. The scheme has very low transaction overhead and can be tuned to use different risk strategies
for different environments and clients.
Keywords Micropayments - trust management - wireless networks - access control