Hi,
Thanks Ted Tronson, Ron Bergman, Carl-Uno Manros, and others.
To clarify: All IPP operations (present and future) will still have
HTTP-level support for 'redirect'. Tom and I are merely proposing
to discard (before the RFC) what we think is a duplicate 'redirect'
mechanism at the IPP-level.
If we ever bind IPP over another transport/session protocol in
the future, we'll probably want to add to the IPP Model an
in-band 'redirect-uri' and 'redirect-job-id' pair of operation
response attributes.
Cheers,
- Ira McDonald
High North Inc
-----Original Message-----
From: Ted Tronson [mailto:TTRONSON at novell.com]
Sent: Thursday, July 18, 2002 12:08 PM
To: ipp at pwg.org
Subject: IPP> Re: FW: Last Call comment to remove redirect URL and
status code fromIPPGET
I see no reason to have the redirection URL. In the past in might have
been a good idea, but in our present implementation I don't think it
would be needed.
Ted Tronson
Sr. Software Engineer
iPrint Engineering
801-861-3338
Novell, Inc., the leading provider of Net services software
www.novell.com
>>> "Hastings, Tom N" <hastings at cp10.es.xerox.com> 07/18/02 09:23AM
>>>Harry, Carl, Hugo, and Ted,
Do any of you want to keep the redirection URL attribute and status
code in
IPPGET, or can we delete it from IPPGET? Ira and I were guessing that
maybe
the idea of redirection may have come from the Novell idea of using a
separate Notification Server for a number of Printers. On the other
hand,
maybe with IPPGET where the Notification Recipient is going the
Get-Notifications operation that maybe each Printer would be more
likely to
do the notification, rather than handing the responsibility off to a
separate Notification Server.
Please see the reasons that Ira and I gave in our Last Call comment on
IPPGET for deleting this application layer redirection from IPPGET.
If you need redirection, you can always use the HTTP redirection.
Thanks,
Tom and Ira
-----Original Message-----
From: Carl [mailto:carl at manros.com]
Sent: Wednesday, July 17, 2002 23:15
To: Hastings, Tom N
Cc: Ira McDonald; Carl-Uno Manros
Subject: RE: Last Call comment to remove redirect URL and status code
from IPPGET
Tom,
Can you still remember who wanted this in there in the first place?
IBM
perhaps? Or Novell?
Would be good to find that out before we delete it, but otherwise I am
for
the simplification.
Carl-Uno
Carl-Uno Manros
10701 S Eastern Ave #1117
Henderson, NV 89052, USA
Tel +1-702-617-9414
Fax +1-702-617-9417
Mob +1-310-251-7103
Email carl at manros.com
> -----Original Message-----
> From: Hastings, Tom N [mailto:hastings at cp10.es.xerox.com]
> Sent: Wednesday, July 17, 2002 6:21 PM
> To: ipp at pwg.org> Cc: Carl
> Subject: Last Call comment to remove redirect URL and status code
from
> IPPGET
>>> Ira McDonald and I were talking about the IPPGET which has a
> "redirect-uri"
> operation attribute that MAY be returned in a Get-Notifications
response
> when the 'redirection-other-site' status code returned. Here is
> all of the
> text in the document that deals with redirection:
>> 5.2 Get-Notifications Response
>> redirection-other-site: The Printer does not handle this operation
and
> requests the Notification Recipient to perform the operation
> again with the
> uri specified by the "redirect-uri" Operation Attribute in the
response.
> See section 10.2.
>> 5.2.3 redirect-uri (uri)
>> The value of this attribute is the uri that the Notification
> Recipient MUST
> use for a subsequent Get-Notifications operation. The Printer MAY
support
> this attribute. This attribute MUST be returned in the Operation
> Attributes
> Group if and only if the Printer returns the
> 'redirection-other-site' status
> code (see section 10.2).
>> 10.2 redirection-other-site (0x0300)
>> This status code means that the Printer doesn't perform that
> Get-Notifications operation and that the "redirect-uri" operation
> attribute
> (see section 5.2.3) in the response contains the uri that the
Notification
> Recipient MUST use for performing the Get-Notifications operation.
If the
> client issues subsequent Get-Notifications operations, it MUST
> use the value
> of the "redirect-uri" operation attribute returned by the Printer as
the
> target of the operation.
>> 12.1 Printer Conformance
>> 8. MUST support the "redirection-other-site" status code defined
10.2,
> if it redirects Get-Notifications operations;
>> Presumably a client MUST support the 'redirection-other-side'
> status code if
> it ever is returned by a Printer in a Get-Notifications response,
though
> section 12.2 Client Conformance doesn't mention this.
>>> We suggest that we delete all of the above text from the IPPGET spec,
so
> that there is no redirect status code and no "redirect-uri"
operation
> attribute for the following reasons:
>> 1. The HTTP Layer already has redirect for all operations, not just
> Get-Notifications. Introducing a competing redirection mechanism
into the
> application layer seems a mistake. What happens if they both occur?
>> 2. Redirection has a number of problems for Get-Notifications, in
> that if a
> Printer is using a Notification Server to return events, along with
other
> Printers, then getting job attributes from the Job object on a job
event
> means that the job-ids for each of the Printers have to be allocated
in a
> non-conflicting way for each of the Printers. Or alternatively,
> the Printer
> needs to return not only a "redirect-uri", but also possibly a
new-job-id,
> if the job id has changed.
>> 3. If we ever wanted to put IPP semantics on another transport, we
can
> decide then whether to introduce the redirection concept into IPP
> application layer for all operations (and fix the problems listed
> above) or
> use the transport's redirect mechanism.
>> 4. Removing this redirect mechanism makes it simpler for a client
using
> Get-Notifications, since the client won't have to deal with it. And
since
> IPPGET is proposed to be the REQUIRED notification method,
simplifying
> IPPGET for clients is a good idea.
>> Comments?
>> Tom
>> -----Original Message-----
> From: Carl [mailto:carl at manros.com]
> Sent: Saturday, July 13, 2002 13:37
> To: ipp at pwg.org> Subject: IPP> ADM - IPP Working Group Last Call for "(IPP): Event
> Notifications and Subscriptions" and "(IPP): The 'ippget'Delivery
Method
> for Event Notifications " by July 31, 2002
>>> All,
>> This is a working group Last Call for the "Internet Printing
> Protocol (IPP):
> Event Notifications and Subscriptions" and the "Internet Printing
Protocol
> (IPP): The 'ippget'Delivery Method for Event Notifications".
> Versions of these documents have been forwarded to the Internet
> Draft directory as <draft-ietf-ipp-not-spec-09.txt> and
> <draft-ietf-ipp-notify-get-07.txt>.
>> PDF and Word versions of the drafts are also posted at the ietf-ipp
web
> site:
>>ftp://ftp.pwg.org/pub/pwg/ipp/>> The Last Call notice follows:
>> This is a formal request for final comments within the IETF IPP
> Working Group for two documents. "Internet Printing Protocol (IPP):
> Event Notifications and Subscriptions" and the "Internet Printing
Protocol
> (IPP): The 'ippget' Delivery Method for Event Notifications", which
have
> earlier been forwarded to the IESG for consideration as Standards
Track
> RFCs. These are IPP Working Group products, which have been
thoroughly
> discussed since mid 1998. The latest revisions are the result of
feedback
> from our Area Director Ned Freed and Working Group discussions
earlier
> this year. The most significant change is that the 'ippget'
> delivery method
> is now mandated for all implementations of the IPP Event
Notifications,
> while additional delivery methods can be used as an option.
>> The purpose of a working group Last Call is in the style of "speak
now or
> forever hold your peace" in case there are fundamental objections,
which
> have not gotten previous or adequate discussion, or minor errors
> which need
> correction.
>> Last Calls are for a minimum of 2 weeks. The period for the Working
Group
> comments will close on July 31, 2002(US Pacific time reference).
>> The relevant documents are:
>> Title : Internet Printing Protocol (IPP): IPP Event
> Notifications and Subscriptions
> Author(s) : R. Herriot, T. Hastings
> Filename : draft-ietf-ipp-not-spec-09.txt
> Pages : 101
> Date : 03-Jul-02
>> This document describes an OPTIONAL extension to the Internet
> Printing Protocol/1.1: Model and Semantics (RFC 2911, RFC 2910).
> This extension allows a client to subscribe to printing related
> Events. Subscriptions are modeled as Subscription Objects. The
> Subscription Object specifies that when one of the specified Events
> occurs, the Printer sends an asynchronous Event Notification to the
> specified Notification Recipient via the specified Push or Pull
> Delivery Method (i.e., protocol).
> A client associates Subscription Objects with a particular Job by
> performing the Create-Job-Subscriptions operation or by submitting a
> Job with subscription information. A client associates Subscription
> Objects with the Printer by performing a
Create-Printer-Subscriptions
> operation. Four other operations are defined for Subscription
> Objects: Get-Subscriptions-Attributes, Get-Subscriptions, Renew-
> Subscription, and Cancel-Subscription.
>> A URL for this Internet-Draft is:
>http://www.ietf.org/internet-drafts/draft-ietf-ipp-not-spec-09.txt>> -----
>> Title : Internet Printing Protocol (IPP): The
'ippget'
> Delivery Method for Event Notifications
> Author(s) : R. Herriot, T. Hastings
> Filename : draft-ietf-ipp-notify-get-07.txt
> Pages : 37
> Date : 03-Jul-02
>> This document describes an extension to the Internet Printing
> Protocol/1.1: Model and Semantics (RFC 2911, RFC 2910). This
> document specifies the 'ippget' Delivery Method for use with the
> 'Internet Printing Protocol (IPP): Event Notifications and
> Subscriptions' specification. When IPP Notification [ipp-ntfy] is
> supported, the Delivery Method defined in this document is the
> REQUIRED Delivery Method for clients and Printers to support. They
> MAY support additional Delivery Methods.
> The 'ippget' Delivery Method is a Pull Delivery Method. When an
> Event occurs, the Printer saves the Event Notification for a period
> of time called the Event Life. The Notification Recipient fetches
> (pulls) Event Notifications using the Get-Notifications operation.
> If the Notification Recipient has selected the Event Wait Mode
option
> to wait for additional Event Notifications, the Printer continues to
> return Event Notifications to the Notification Recipient as Get-
> Notification responses as Events occur using the connection
> originated by the Notification Recipient.
> Either the Notification Recipient or the Printer can terminate Event
> Wait Mode without closing the connection.
>> A URL for this Internet-Draft is:
>http://www.ietf.org/internet-drafts/draft-ietf-ipp-notify-get-07.txt
>> Sincerely,
>> Carl-Uno Manros
> Chair of the IETF IPP WG
>> 10701 S Eastern Ave #1117
> Henderson, NV 89052, USA
> Tel +1-702-617-9414
> Fax +1-702-617-9417
> Mob +1-310-251-7103
> Email carl at manros.com>>