| 摘要 |
<p>The invention is concerned with systems for transferring value between electronic purses, usually in the form of IC or 'Smart' cards, via the intermediary of an interface device. In order to control the flow of value between purses a hierarchical class structure is proposed. This is achieved by assigning to each purse a class which controls the conditions under which value may be transferred to an from (mainly from) a purse. Thus each purse stores in memory a representation of its own class, together with a list of those classes to which the purse can transfer value.</p> |
