A Secure, Cheap, Scalable and Exportable/importable Method for Internet Electronic Payments

We propose cryptographic protocols for electronic payment transactions over the Internet. Three essential requirements are met. (1) Security: this consists of entity authentication of each party involved, message integrity protection, strong non-repudiation on payment order and high degree of fault tolerance. (2) Economy: a payment transaction will be completed with the involvement of the conventional parties, i.e., the client, the merchant and the nancial institution; the method does not employ any other specialised services, such as public-key certifying or Kerberos-like authen-tication. (3) International compatibility: no decryption algorithm will be used for secret retrieval; no non-exportable/non-importable cryptographic technology will be applied; thus, the method will be acceptable by the governments of various nations and can be scaled up to run in numerous nancial institutions. The method uses one-way hashed values of passwords which are centrally stored in nancial institutions. Being unable to nd the clear passwords allows nancial institutions to qualify as authentication agents.