From: J.B.Moreno (planb@newsreaders.com)
Date: Thu Feb 05 2004 - 00:25:43 CST
On 2/4/04 8:43 AM, Charles Lindsey at <chl@clerew.man.ac.uk> wrote:
> Russ Allbery <rra@stanford.edu> writes:
>> No, if we're using injection-date for the staleness check, it may not ever
>> be overwritten or modified, for the same reason that we require the server
>> not modify the Date header. Doing anything else breaks Usenet's loop
>> detection algorithm and potentially allows reinjection of stale messages.
>
> No, I don't think it is as simple as that. We need to analyze the reasons
> why double injection occurs. My belief is that the commonest cause will be
> because there is confusion or disagreement as to who is doing the actual
> injection (and especially so since INN has implemented "IHAVE for anybody"
> which either injects or relays according to how well it trusts the
> client).
That's a certainly a contributing cause, but fundamentally it's irrelevant
-- the problem is accepting stale messages. The only way to see how fresh
an article is is to have a header that contains a timestamp, replacing that
timestamp with a newer one, for whatever reason, can result in double
injection.
I don't agree with the need to replace Date, I think having it as the
injection time acceptable. But if it is replaced, then it's replacement will
need to have the same constraints on modifying it, i.e. don't do that. You
can accept or reject, but if you change timestamp you're just asking for
double injection problems.
-- J.B. Moreno