Re: #1586: Re: ISSUE: treatment of POSTED in proto articles

In <[email protected]> Harald Tveit Alvestrand <[email protected]> writes:

>I have recorded this as issue #1586.

>>>> 3.4.1.  Proto-articles
>>>>
>>>>    A proto-article has the same format as a normal article except that
>>>>    the Injection-Info and Xref header fields MUST NOT be present; the
>>>>    Path header field MUST NOT contain a "POSTED" <diag-keyword>; and any
>>>>    of the following mandatory header fields MAY be omitted: Message-ID,
>>>>    Date, and Path.  In all other respects, a proto-article MUST be a
>>>>    valid Netnews article.  In particular, the header fields which may be
>>>>    omitted MUST NOT be present with invalid content.
>>>>
>>>> I am worried about that 'MUST NOT contain a "POSTED" <diag-keyword>'. It
>>>> would cause no interoperability problems and cause no significant harm,
>>>> and hence a "MUST" cannot be justified under RFC 2119. Nothing breaks if
>>>> two "POSTEDs appear in one Path.  Indeed, it could arise legitimately in
>>>> multiple injection "after the fact", and in other exotic gatewaying
>>>> situations.
>>>>
>>>> Yes, some s[pc]ammers will preload the Path so as to disguise the true
>>>> origin of an article (which is indeed why POSTED was invented), but that
>>>> is a matter to be taken up by the netkops rather than the protocols. And
>>>> I would prefer to preserve all evidence left over from previous Paths in
>>>> order to facilitate bebugging of broken gateways, etc.
>>>>
>>>> So, at the most, it ought to be a SHOULD, and I would be happy to omit
>>>> it altogether. Note that whatever change is made here, corresponding
>>>> changes would be needed in 3.4.2 and 3.5.2 Step 2.
>>>>       
>>
>>   
>>> This is also a protocol change and should therefore be a separate issue.
>>> I'm inclined to agree with you that MUST isn't justified here and SHOULD
>>> is more appropriate.  I think we already talked about this before,
>>> although I haven't gone back and looked.
>>>     
>>
>> OK, here it is. I note that you agree that MUST is too strong.

OK, I think at least s/MUST/SHOULD/ is necessary (no interoperability
implication), as Russ seems to agree.

So it is just a matter of whether to make it lower than SHOULD, on the
grounds given below. But, at this late stage I would settle for that
SHOULD if noone else speaks up. However, I really think it wrong to remove
evidence that might be helpful later, so I would encourage others to look
at this and comment here.

>> However, I think SHOULD (and perhaps even MAY) is too strong. The protocol
>> use to prevent loops is not affected by this change. But the Path is also
>> important for diagnosing the cause of loops (not necessarily
>> non-terminating ones) such as those caused by peculiar gatewaying, and for
>> spotting trollers who try to disguise the source of their articles.
>>
>> So seeing two 'POSTED's in a Path should immediately raise alarm bells
>> (even though it may occasionally turn out to have a benign explanation).
>> But if duplicate 'POSTED's are removed, then no alarm bells will be
>> heard. So leave them in, and let the Debuggers and the Netkops take care
>> of them.
>>
>> In either case, there would be consequential changes elsewhere, as noted.
>>
>>   


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