American Express plans embedding of the chip programmed on the Proton technology in the cards. "The electronic purse" will be used, according to representatives of the company, is exclusive in the sphere of small payments: for payment of journey in public transport, shopping in vending machines, phone calls, etc.
In cards with the unprotected memory there are no restrictions on reading or data recording. Sometimes they are called cards with fully accessible memory; work with them (in sense of logical structure of data) reminds work with the binary file. It is possible to structure randomly the card at the logical level, considering her memory as a set of bytes which can be copied in random access memory or to update special teams.
As a rule, the cryptographic means providing enciphering of information and development of the "digital" signature are built in such cards. Traditionally in cards the cryptographic algorithm of DES is applied to these purposes. Besides, in a card there are means of maintaining key system.
- it is inaccessible. This mode does not allow to read or write down information. Information is available only internal programs of mothers of a card. Usually this mode is set for the records containing cryptographic keys.
Results of the Belgian project give rather clear idea of the market of "electronic money". First, it it is considerable already, than the market of small payments in general: it is not necessary to speak about replacement of cash also so far. Secondly, the turnover of means of "electronic purses" is very small in comparison, say, with traditional debit cards. And, at last, thirdly, the small subset of the market of small payments into which electronic money fits most harmoniously, purchases in vending machines appears.
- Reliability of use. After entering on a smart card of all data of the owner communication with a database happens immediately upon presentation of the card that is very important for the cities in which there are no modern telecommunication means.