U-PAI: A Universal Payment Application Interface

The progress of electronic commerce has been stymied by the lack of widely accepted network payment mechanisms. A number of proposals have been put forward, and each one o ers a slightly di erent protocol and set of features. Yet none has achieved the critical mass to become an accepted standard. We believe that there will continue to be a variety of payment mechanisms, so in this paper we propose U-PAI, a universal payment application interface that will enable a programmer to write for one interface, and then interact with any payment mechanism. Each payment mechanism can support the universal API directly, or a proxy or wrapper can be built to translate U-PAI calls to the appropriate native calls supported by the payment mechanisms. In this paper we illustrate how two such proxies could be built. We also provide, in the appendix, a full CORBA speci cation of U-PAI.