s-o-1036 June 1994
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6.7. Distribution
The Distribution header content specifies geographic or
organizational limits on an article's propagation:
Distribution-content = distribution *( dist-delim distribution )
dist-delim = ","
distribution = plain-component
A distribution is syntactically identical to a one-component
newsgroup name, and must satisfy the same rules and restric-
tions. In the absence of Distribution, the default distri-
bution is "world".
NOTE: This syntax has the disadvantage of contain-
ing no white space, making it impossible to con-
tinue a Distribution header across several lines.
Implementors of relayers and reading agents are
warned that it is intended that the successor to
this Draft will change the definition of dist
delimiter to:
dist-delim = "," [ space ]
and are urged to fix their software to handle
(i.e., ignore) white space following the commas.
A relayer MUST not pass an article to another relayer unless
configuration information specifies transmission to that
other relayer of BOTH (a) at least one of the article's
newsgroup(s), and (b) at least one of the article's distri-
bution(s). In effect, the only role of distributions is to
limit propagation, by preventing transmission of articles
that would have been transmitted had the decision been based
solely on newsgroups.
A posting agent might wish to present a menu of possible
distributions, or suggest a default, but normally SHOULD not
supply a default without giving the poster a chance to over-
ride it. A followup agent SHOULD initially supply the same
Distribution header as found in the precursor, although the
poster MAY alter this if appropriate.
Despite the syntactic similarity and some historical confu-
sion, distributions are NOT newsgroup names. The whole
point of putting a distribution on an article is that it is
DIFFERENT from the newsgroup(s). In general, a meaningful
distribution corresponds to some sort of region of propaga-
tion: a geographical area, an organization, or a cooperating
subnet.
NOTE: Distributions have historically suffered
from the completely uncontrolled nature of their
name space, the lack of feedback to posters on
INTERNET DRAFT to be NEWS sec. 6.7
incomplete propagation resulting from use of ran-
dom trash in Distribution headers, and confusion
with newsgroups (arising partly because many
regions and organizations DO have internal news-
groups with names resembling their internal dis-
tributions). This has resulted in much garbage in
Distribution headers, notably the pointless prac-
tice of automatically supplying the first compo-
nent of the newsgroup name as a distribution
(which is MOST unlikely to restrict propagation!).
Many sites have opted to maximize propagation of
such ill-formed articles by essentially ignoring
distributions. This unfortunately interferes with
legitimate uses. The situation is bad enough that
distributions must be considered largely useless
except within cooperating subnets that make an
organized effort to restrain propagation of their
internal distributions.
NOTE: The distributions "world" and "local" have
no standard magic meaning (except that the former
is the default distribution if none is given).
Some pieces of software do assign such meanings to
them.
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#Diff to first older
--- ../rfc1036/Distribution.out December 1987
+++ ../s-o-1036/Distribution.out June 1994
@@ -1,26 +1,83 @@
-2.2.7. Distribution
+6.7. Distribution
- This line is used to alter the distribution scope of the message.
- It is a comma separated list similar to the "Newsgroups" line. User
- subscriptions are still controlled by "Newsgroups", but the message
- is sent to all systems subscribing to the newsgroups on the
- "Distribution" line in addition to the "Newsgroups" line. For the
- message to be transmitted, the receiving site must normally receive
- one of the specified newsgroups AND must receive one of the
- specified distributions. Thus, a message concerning a car for sale
- in New Jersey might have headers including:
-
- Newsgroups: rec.auto,misc.forsale
- Distribution: nj,ny
-
- so that it would only go to persons subscribing to rec.auto or misc.
- for sale within New Jersey or New York. The intent of this header
- is to restrict the distribution of a newsgroup further, not to
- increase it. A local newsgroup, such as nj.crazy-eddie, will
- probably not be propagated by hosts outside New Jersey that do not
- show such a newsgroup as valid. A follow-up message should default
- to the same "Distribution" line as the original message, but the
- user can change it to a more limited one, or escalate the
- distribution if it was originally restricted and a more widely
- distributed reply is appropriate.
+The Distribution header content specifies geographic or
+organizational limits on an article's propagation:
+
+ Distribution-content = distribution *( dist-delim distribution )
+ dist-delim = ","
+ distribution = plain-component
+
+A distribution is syntactically identical to a one-component
+newsgroup name, and must satisfy the same rules and restric-
+tions. In the absence of Distribution, the default distri-
+bution is "world".
+
+ NOTE: This syntax has the disadvantage of contain-
+ ing no white space, making it impossible to con-
+ tinue a Distribution header across several lines.
+ Implementors of relayers and reading agents are
+ warned that it is intended that the successor to
+ this Draft will change the definition of dist
+ delimiter to:
+
+ dist-delim = "," [ space ]
+
+ and are urged to fix their software to handle
+ (i.e., ignore) white space following the commas.
+
+A relayer MUST not pass an article to another relayer unless
+configuration information specifies transmission to that
+other relayer of BOTH (a) at least one of the article's
+newsgroup(s), and (b) at least one of the article's distri-
+bution(s). In effect, the only role of distributions is to
+limit propagation, by preventing transmission of articles
+that would have been transmitted had the decision been based
+solely on newsgroups.
+
+A posting agent might wish to present a menu of possible
+distributions, or suggest a default, but normally SHOULD not
+supply a default without giving the poster a chance to over-
+ride it. A followup agent SHOULD initially supply the same
+Distribution header as found in the precursor, although the
+poster MAY alter this if appropriate.
+
+Despite the syntactic similarity and some historical confu-
+sion, distributions are NOT newsgroup names. The whole
+point of putting a distribution on an article is that it is
+DIFFERENT from the newsgroup(s). In general, a meaningful
+distribution corresponds to some sort of region of propaga-
+tion: a geographical area, an organization, or a cooperating
+subnet.
+
+ NOTE: Distributions have historically suffered
+ from the completely uncontrolled nature of their
+ name space, the lack of feedback to posters on
+
+INTERNET DRAFT to be NEWS sec. 6.7
+
+
+ incomplete propagation resulting from use of ran-
+ dom trash in Distribution headers, and confusion
+ with newsgroups (arising partly because many
+ regions and organizations DO have internal news-
+ groups with names resembling their internal dis-
+ tributions). This has resulted in much garbage in
+ Distribution headers, notably the pointless prac-
+ tice of automatically supplying the first compo-
+ nent of the newsgroup name as a distribution
+ (which is MOST unlikely to restrict propagation!).
+ Many sites have opted to maximize propagation of
+ such ill-formed articles by essentially ignoring
+ distributions. This unfortunately interferes with
+ legitimate uses. The situation is bad enough that
+ distributions must be considered largely useless
+ except within cooperating subnets that make an
+ organized effort to restrain propagation of their
+ internal distributions.
+
+ NOTE: The distributions "world" and "local" have
+ no standard magic meaning (except that the former
+ is the default distribution if none is given).
+ Some pieces of software do assign such meanings to
+ them.