Properties of E-cash

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 ELECTRONIC CASH – 4 Properties

1. Monetary value:

  • It must be backed by either cash(currency), bank-authorized credit, or a bank-certified cashier’s check.
  • It must not be returned for insufficient funds when deposited.

2. Interoperability:

  • Exchangeable as payment for other e-cash, paper cash, goods or services, lines of credit, deposits in banking accounts, etc.
  • Multiple banks are required with an international clearinghouse.

3. Retrievability:

  • remote storage and retrieval ( from a mobile/personal communication device) would allow users to exchange e-cash from home/office / while traveling.
  • The cash could be stored on a remote computer’s memory, in smart cards, or in other easily transported standard or special-purpose devices.
  • It's preferable to store cash on a dedicated device that cannot be altered.

4. Security:

  • The device should have a personal interface to facilitate personal authentication using passwords or other means and a display so that users can view the card contents.
  • Eg: Montex card – A pocket-sized electronic wallet that can store e-cash.
  • E-cash should not be easy to copy or tamper with while being exchanged.
  • Prevent/detect duplication and double-spending.
  • Double spending: use your e-cash simultaneously to buy something in Japan, India, and England.



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