IETF has announced the publication of an Informational RFC on Requirements and Design for Voucher Trading System (VTS). Several Internet Drafts and RFCs on a Generic Voucher Language 'XML Voucher' and 'Voucher Trading System (VTS)' have been released through the activities of the IETF Internet Open Trading Protocol Working Group. The VTS requirements document calls for implementation of the Voucher Trading System based upon a Voucher Trading Protocol (VTP), VTS Application Programming Interface (VTS-API), and an XML-based Generic Voucher Language (GVL). These specifications are being designed to interoperate with the Internet Open Trading Protocol (IOTP) and with the Electronic Commerce Modeling Language (ECML) specification, as well as with the XML Recommendation and XML-Signature. The Voucher Trading System addresses the need to credit loyalty points and collect digital coupons or gift certificates, which are "common functions in purchasing and trading transactions. These activities are generalized using the concept of a voucher, which is a digital representation of the right to claim goods or services."

Bibliographic Information

• Requirements and Design for Voucher Trading System (VTS). By Ko Fujimura (NTT Corporation) and Donald E. Eastlake 3rd (Motorola). IETF Network Working Group. Request for Comments: #3506. Category: Informational. March 2003. 15 pages. "Crediting loyalty points and collecting digital coupons or gift certificates are common functions in purchasing and trading transactions. These activities can be generalized using the concept of a 'voucher', which is a digital representation of the right to claim goods or services. This document presents a Voucher Trading System (VTS) that circulates vouchers securely and its terminology; it lists design principles and requirements for VTS and the Generic Voucher Language (GVL), with which diverse types of vouchers can be described... To achieve consistency with other related standards shown below, the syntax of the language must be based on XML... The language specification should be consistent with the following specifications: (1) Internet Open Trading Protocol v1.0; (2) XML-Signature; (3) Extensible Markup Language (XML) Recommendation; (4) ECML Version 2."

• XML Voucher: Generic Voucher Language. By Ko Fujimura and Masayuki Terada (NTT Corporation, Yokosuka-shi, Kanagawa, Japan). With contributions by Donald Eastlake 3rd, Ian Grigg, Renato Iannella, and Yoshiaki Nakajima. IETF Trade Working Group, Internet-Draft. Reference: 'draft-ietf-trade-voucher-lang-05.txt'. February 2003, expires August 2003. 19 pages. "This document specifies rules for defining voucher properties in XML syntax. A voucher is a logical entity that represents a right to claim goods or services. A voucher can be used to transfer a wide-range of electronic-values, including coupons, tickets, loyalty points, and gift certificates, which are often necessary to process in the course of payment and/or delivery transactions... The motivation and background of the specification are described in Requirements and Design for Voucher Trading System (VTS)... A voucher is generated by the issuer, traded among users, and finally collected by the collector using VTS... This document defines the syntax and semantics of Voucher Component, which defines voucher meaning and processing rules in XML syntax. A Voucher Component defines the properties that must be satisfied to allow the voucher to be processed by VTS or other trading systems, e.g., wallet or merchant system. VTS definitions and models are also defined in "Requirements and Design for Voucher Trading System (VTS)."

• Voucher Trading System Application Programming Interface (VTS-API). By Ko Fujimura and Masayuki Terada (NTT Corporation, Yokosuka-shi, Kanagawa, Japan). IETF Trade Working Group, Internet-Draft. Reference: 'draft-ietf-trade-voucher-vtsapi-05.txt'. February 2003, expires August 2003. 26 pages. "This document specifies the Voucher Trading System Application Programming Interface (VTS-API). The VTS-API allows a wallet or other application to issue, transfer, and redeem vouchers in a uniform manner independent of the VTS implementation. The VTS is a system to securely transfer vouchers, e.g., coupons, tickets, loyalty points, and gift certificates; this process is often necessary in the course of payment and/or delivery transactions... The VTS-API allows a caller application to issue, transfer, and redeem vouchers in a uniform manner independent of the VTS implementation. Several attempts have been made at providing a generic payment API. Java Commerce Client and Generic Payment Service Framework, for example, introduce a modular wallet architecture that permits diverse types of payment modules to be added as plug-ins and supports both check-like/cash-like payment models. This document is inspired by these approaches but the scope of this document is limited to the VTS model, in which cash-like payment model is assumed and vouchers are directly or indirectly transferred between sender (transferor) and receiver (transferee) via the VTS. This document is not intended to support API for SET, e-check or other payment schemes that do not fit the VTS model. Unlike the APIs provided in JCC and GPSF, which are designed to transfer only monetary values, this API enables the transfer of a wide-range of values through the use of XML-based Generic Voucher Language. The monetary meaning of the voucher is interpreted by the upper application layer using the information described in the language. This approach makes it possible to provide a simpler API in the voucher-transfer layer and enhances runtime efficiency. The API specification in this document is described in the Java language syntax. Bindings for other programming languages may be completed in a future version of this document or separate related specifications..."

Voucher Conceptual Model

Key concepts (adapted from the March 2003 RFC): A voucher is a digital representation of the right to claim goods or services. To clarify the difference between vouchers and electronic money/digital certificates, we introduce a formal definition of vouchers in this document. Let I be a voucher issuer, H be a voucher holder, P be the issuer's promise to the voucher holder. A voucher is defined as the 3-tuple of <I, P, H>. A Examples of an issuer's promise include awarding and redemption of loyalty points, purchase discount based upon use of a membership card, price reduction based upon a coupon, free accesss to an online resource for a period of time, an exchange ticket or delivery note, or reservation for a particular seat at an event on a certain date. An issuer's promise P does not need to be described in terms of a natural language as long as the contents of the vouchers are specified. For example, a set of attribute name and value pairs described in XML can be employed to define the contents. There are four types of participants in the voucher trading model: issuer, holder, collector, and VTS provider. (1) An Issuer Creates and issues a voucher and guarantees the contents of the voucher. (2) A Holder (or user) owns the vouchers; a holder transfers and redeems the voucher to other users or collector. (3) A Collector (or examiner) collects or examines the voucher and implements its promise. In general, the collector is compensated by goods or services rendered. (4) A VTS Provider provides a VTS and guarantees that a particular voucher is not assigned to multiple holders or used multiple times unless permitted for that voucher type. The IETF IOTP model includes merchant, deliverer, consumer and other participants. They take various roles in the settlement because a merchant, for example, can be considered as an issuer, or holder depending on whether the merchant creates the voucher her/himself or purchases it from a wholesaler or manufacturer. A merchant can also be a collector if the shop collects gift certificate or coupons.