Delivery time expiration

[Scot L. Harris]

On Tue, 2006-02-14 at 09:40 +1030, Tim wrote:
> Tim:
> >> But how much real mail gets stuffed up?  I've seen many different
> >> anti-spam techniques that cause more problems than they solve,
> >> leaving some hapless author in a position that they don't know
> >> what went wrong, nor have any way to sort out a solution.
> 
> Mike Klinke:
> > "Stuffed Up"?  Does this mean "not delivered"?  If so, it's easy for 
> > a mail admin to see whether a message is continuously hitting the 
> > greylisting block mechanism.
> 
> Yes.  But what about where there is no mail "admin"?  What happens when
> John Doe e-mails someone, and it comes back to him.  He posts again, and
> it comes back to him.  The ISP's mail servers are out of his control.
> Many ISPs have next to useless support staff.
> 
> Does this person manage to get his mail through, or does he give up?
> 

If the email is important would the person sending the email phone the
other person to find out what the problem is?  Then that person can be
put on the whitelist.  In my experience that has not been needed.  Most
legit MTAs are well behaved and play by the RFCs.  

> > In nearly two years of running greylisting I've not had a problem with
> > failed deliveries so far and some of my normal correspondents do use
> > rotating mail servers for their outgoing mail.
> 
> This does beg the obvious question:  Do you get to find out about it if
> someone can't post?
> 

If it was important wouldn't the sender phone?

> > However, if "stuffed up" simply means "delayed" then yes ALL mail 
> > gets delayed ( unless added to a whitelist ), some more than others 
> > depending on the mail server's retry cycle.
> 
> I don't mind e-mail being non-instant, but when you have cases of some
> messages taking hours, if not somewhere around a day, to get delivered,
> I dislike that sort of delay.  It can make e-mail useless for some
> circumstances.

Those circumstances are rare.  The perceived need for instantaneous
email and the actual need for it are two very different things.