[ietf-nntp] OVER message-id

[Francois Petillon]

Andrew - Supernews wrote:
>  Ken> If a server can fetch an entire article by msgid, is it that far
>  Ken> of a reach to get the overview data?
> is typical of that, because it _is_ a reach - a distributed server
> design (such as, for instance, Diablo) separates the article store
> (accessed by message-id) from all the per-group and overview
> information (accessed by group/article number). In such a system it is
> highly desirable to be able to store articles without knowing their
> assigned article numbers (and hence not being able to store the Xref).

The problem is not to know if it is desirable or not. The problem is to 
know if the data retreived are valuable. A spooler may store articles 
for different news servers using unsynchronized xref (it may be a usenet 
provider for different ISPs or a backoff spooler shared by different 
news servers) and will give inappropriate information. To manage "over 
M-ID", we need to retrieve the article on a spooler, selecting an 
existing newsgroup & the M-ID, oppening newsgroup overview and looking 
for the M-ID. Quite costy...

>>> For the same technical reasons, he suggests that:
>>> HDR Xref <message-id>
>>> HDR :lines <message-id>
>>> may be problematical.
>  Ken> Same as above, client authors should determine if its useful.

Same as above, requesting overview/header information by M-ID is quite 
harmful to Diablo/dreaderd. As far as I am concerned, I really dislike
requesting an article on a spooler just to extract header informations
(specially when the information may be false) but adding a reversed 
history on dreaderd will be as costy in I/Os...

   François