<p>Value based tokens are generated for inclusion on a data carrier which may be applied to a media such as a coupon, bank note etc. The tokens are generated by a core system which communicates with application specific wrappers. The wrappers supply token parameters to the core that are specific to the application and the core generates the tokens, and stores them for later authentication. The core then encodes the tokens onto a data carrier under the control of the wrapper and distributes the tokens under the control of the wrapper. When a token is presented for validation, for example by a customer in a shop, the encoded data carrier is scanned and the token retrieved. It is passed back to the core by the wrapper for validation of its identification number and other parameters.</p>
