RFC 1026 (rfc1026) - Page 3 of 4
Addendum to RFC 987: (Mapping between X
Alternative Format: Original Text Document
RFC 1026 September 1987
To allow the mapping of null organisations to be represented in the
specification of Appendix F, the dmn-orname syntax is extended, so
that values may be given the symbol "@" (not a printable string
character). This corresponds to an omitted attribute. The new
definition is:
dmn-orname = dmn-part *( "." dmn-part )
dmn-part = attribute "$" value
attribute = standard-type
/ "~" dmn-printablestring
value = dmn-printablestring
/ "@"
dmn-printablestring
= *( dmn-char / dmn-pair )
dmn-char =
dmn-pair = "."
Appendix F - Format of address mapping tables
A new Appendix F is defined as follows:
There is a need to specify the association between the domain and
X.400 namespaces described in 4.2.1. This is defined as a table
syntax, but the syntax is defined in a manner which makes it suitable
for use with domain nameservices (such as the Internet Domain
nameservers or the UK NRS). The mapping is not symmetric, and so a
separate table is specified for each direction. If multiple matches
are possible, the longest possible match should be used.
Various restrictions are placed on the usage of dmn-orname:
1) Only C, ADMD, PRMD, O, and OU may be used.
2) There must be a strict ordering of all components, with the most
significant components on the RHS.
3) No components may be omitted from the hierarchy, although the
hierarchy may terminate at any level. If the mapping is to an
omitted component, the "@" syntax is used.
For domain -> X.400:
domain-syntax "#" dmn-orname "#"
Note that the trailing "#" is used for clarity, as the dmn-orname
syntax can lead to values with trailing blanks.
For example:
AC.UK#PRMD$DES.ADMD$BT.C$UK#
XEROX.COM#O$Xerox.ADMD$ATT.C$US#
Kille