ietf-nntp Section 11.5 - NEWNEWS

[Paul Overell]

In article <20001121154022.F79388 at demon.net>, Clive D.W. Feather
<clive at demon.net> writes
>Paul Overell said:
>> Because in 1986 (the date of RFC977) the basis of civil time was (and
>> still is) UTC.
>
>Where ? Because in the United Kingdom the basis of civil time was and is
>GMT. Allow me to point you at:
><http://www.hmso.gov.uk/si/si1997/97298201.htm>
>(The Summer Time Order 1997), the Interpretation Act 1978, and the
>Definition of Time Act 1880 (the latter two don't appear to be on the Web).
>
>The Coordinated Universal Time Bill never got through Parliament.
>

Got me :)


However, even in the UK (despite the law) all normal time sources
(speaking clock, radio pips, TV, Big Ben etc) are in UTC not GMT.

I am arguing that as the authors of RFC977 did not discuss timescales in
specifying NEWNEWS and NEWGROUPS they were, therefore, assuming that the
time and date were in the normal, everyday, common or garden timescale.
This is UTC, not GMT.  Their use of the token "GMT" was as a timezone
not as a timescale.

Therefore for compatibility with RFC977 (and the real world) the
NEWNEWS, NEWGROUPS and DATE command should all use UTC.


>>> If we give a quantity, the client knows how much slack to allow when doing
>>> the DATE/NEWNEWS thing. I think that's a good idea.
>> 
>> I fully agree that recommending that clients use some slack with NEWNEWS
>> and NEWGROUPS is a good idea - that's just good defensive programming.  
>> 
>> I'm far less happy about specifying an explicit tolerance on a server's
>> clock.  If the server has the same inaccuracy as the client slack then
>> we are right at the edge of losing articles in NEWNEWS.
>
>But if my client allows 3 minutes and the server is out by 5 minutes I'm in
>trouble anyway. What is a sensible aount of slack ? We should say. 
>

Turnpike uses 10 min slack if the client has not synchronized its clock
with a time server, and 2 min slack if it has.


Regards
-- 
Paul Overell                                             T U R N P I K E