Over deze norm
This document specifies a recommended procedure for the development of specifications for applications of digital postage marks (DPMs) - i.e. applications linked to the use of digital printing and image data capture technologies in the postal industry, most particularly for the evidencing of postage accounting and/or payment. It is not intended to prescribe or to recommend any particular architecture or design for such applications, only to specify the process through which such an architecture or design should be developed. The process described is based on a cyclic model, involving business planning; systems analysis; security analysis and detailed DPM design. The defined process is a recommended one only and DPM applications designers are not obligated to follow it. However, its use is intended to ensure both that all relevant aspects are taken into account in the design process and that the resulting specifications have a degree of commonality of structure which make them comparable with similar specifications produced by other parties. It is hoped that this will make them more easily intelligible, and less open to ambiguity, for implementers. It is assumed that users of the standard are familiar with normal processes involved in the design of computerbased applications and the standard therefore limits itself to aspects which are specific to DPM applications design. In particular, the document covers only requirements and considerations relating to applications that use digital postage marks, on individual postal items, as a means of communicating data (messages). The clause on design covers only the design of the digital postage marks themselves. It does not cover other aspects of design, including the possible use of other messages, transported by other means (e.g. statements of mailing), to provide for the communication of additional data, even though these might be just as important. The standard assumes, but does not require, that it is desired to implement digital postage marks which conform to UPU standards S27, S28 and S25 (see Bibliography) and provides a guide to the use of these standards. However, many of the guidelines, recommendations and checklists would apply equally to the design of DPM applications using digital postage marks based on symbologies other than those supported by S28, or requiring data which cannot be accommodated within S25-defined data constructs.