Patent attributes
A portable terminal (10) for encrypting information is described. The terminal (10) generates a new key for each transaction, where the new key is generated using one or more properties of the terminal (10). The one or more properties are variable and may include the history of usage of the terminal, and/or the date and time settings. The terminal (10) may generate a unique challenge in addition to the new key so that a unique challenge can be issued for each transaction. A method of encrypting information in a portable terminal, a method of communicating encrypted information between a portable terminal and a self-service terminal, and a transaction system comprising a self-service terminal (52) and a portable terminal (10) are also described.
