BS 7521:1992

This standard BS 7521:1992 Specification for electronic messaging enabling the application of BS ISO/IEC 10021 in the United Kingdom is classified in these ICS categories:

• 35.240.20 IT applications in office work

1.1 This British Standard specifies the United Kingdom requirements for those matters that BS ISO/IEC 10021 leaves open for national decision, namely:

1. whether UK Private Management Domain (PRMD) names are to be nationally unique, or unique only within the scope of an Administration Management Domain (see 5.1);
2. whether UK Organization names are to be nationally unique, or unique only within the scope of a Management Domain (see 6.1);
3. whether UK ADMDs are to be required to form a National Message Transfer Backbone, i.e. should they be interconnected (see 10.1);
4. whether the users of PRMDs registered with more than one UK ADMD will have to have multiple alias O/R addresses, each relative to one of those ADMDs, or whether ADMDs will be required to recognize the reserved value of the single space (“ ”) to identify the union of all UK ADMDs [see 4.2.3 b)];
5. whether equivalence rules are to be imposed regarding those O/R address Standard Attributes represented as Teletex Strings and their Printable String equivalents (see clause 8);
6. whether the Private Domain Identifier is identical with the Private Domain name (see 5.2.3).

It thereby enables the application of BS ISO/IEC 10021 in the United Kingdom.

NOTE 1 In some cases, the need for a national decision is explicitly identified by BS ISO/IEC 10021, while in others, e.g. the use of the country-name standard attribute, the need is implicit.

NOTE 2 The background to the national decisions is described in Appendix B.

1.2 This British Standard also specifies the procedures to be followed by BS ISO/IEC 10021 Management Domains subordinate to the UK Name Registration Authority (see BS 7453-1).

NOTE The titles of the publications referred to in this standard are listed on the inside back cover.

Specifies how UK Administrative Management Domains (UK ADMDs) and UK Private Management Domains are named; how UK ADMDs connect to form the UK Message Transfer Backbone; and the resolution of other matters left open for national decision in BS ISO/IEC 10021.