IPP Mail Archive: Re: IPP> NOT - Agreements to the IPP Notification Model

Re: IPP> NOT - Agreements to the IPP Notification Model

Hugo Parra (HPARRA@novell.com)
Fri, 20 Aug 1999 11:40:02 -0600

Tom wrote:

> 13. Defined the "subscription-id" attribute for use =
with
> Per-Job subscriptions as being the index of the 1setOf collection, =
starting
> at '1'. Then a Notification Recipient can have a unique identification =
for
> each subscription whether it be Per-Job or Per-Printer, for use in =
catching
> duplicate or skipped notifications using the "request-id".=20
=09
If "request-id"s enable recipients to identify duplicate, skipped, and =
out-of-order notifications associated with the same subscription, and =
"subscription-id"s identify notification threads associated with the same =
subscription, shouldn't printers try harder to make subscription ids =
unique not just across its own subscriptions, but in the network? I'm not =
suggesting that printers listen on the wire to try to come up with unique =
subscription ids, but simply generate them randomly (at least the first =
one).

If all printers start their subscription ids at '1', recipients are much =
more likely to get notifications from different printers with matching =
request ids (consider the scenario where a print server hosts several =
hundred printers: they all come up and down at about the same time and may =
experience similar usage patterns). Recipients will be forced to examine =
the notification's printer-uri's each time to unequivocally determine the =
subscription associated with the notification.

-Hugo