Consumers have a low level of anonymity if they want to
spend coins directly after withdrawing them from the bank.
They can achieve a high level of anonymity through the
AP agent without revealing their private information and
are more secure in relation to the bank because certification
comes from the AP agent, who is not involved in the
payment process. There is little research available on RBAC
for electronic cash schemes. We first canvas RBAC for
payment schemes in this paper. With RBAC, the conflicts of
different roles can be reduced and the complexities of the
scheme can be decreased. The duty separation constraints
of roles, role hierarchies, and scenarios of end-users are
discussed in details.
The authors would like to thank the reviewers for their
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Hua Wang received the PhD degree in compu-
ter science from The University of Southern
Queensland in 2003. He is a lecturer at the
University of Southern Queensland, Australia.
He has been active in the areas of information
systems manag ement, distributed database
management systems, access control, software
engineering, and electronic commerce. He has
participated in rese arch projects o n mobile
electronic systems, Web services, and role-
based access control for electronic service systems. He has published
more than 30 research papers in refereed international journals and
conference proceedings. Dr. Wang is a technical PC member of APWeb
’05 and ACSC 2005.
WANG ET AL.: A FLEXIBLE PAYMENT SCHEME AND ITS ROLE-BASED ACCESS CONTROL 435