RE: MFD> Scan Service Sectionr 10

From: William A Wagner (wamwagner@comcast.net)
Date: Mon Feb 02 2009 - 22:45:25 EST

  • Next message: Ira McDonald: "Re: MFD> Scan Service Sectionr 10"

    Ira,

    I am sorry, I am not following you at all.

    I made no suggestion that the state tables be deleted. Indeed, insofar as
    the state of the Service affects the response to interfaces/operation
    requests, I agree that the states and the actions effecting transitions be
    clearly stated.

    I made no objection to maintaining that StartupScanService goes to the
    System to initiate a Scan Service instantiation; I do maintain that, if that
    is the path, it should be identified as such and System should be defined in
    the document.

    Since Down is in the Offline phase, I find it confusing that a Service in
    the Down state would accept SOAP requests.

    There currently are no references to ISO 10175. To the extent that
    information in that document is applicable, I have no problem to referring
    to it. I do have a problem in assuming the reader has full familiarity with
    contents of that document to the extent that terms do not need to be defined
    in the Scan Service document, indeed not even by reference.

    Including a DeleteService (directed to a system) is nice for a symmetrical
    model, but it is not in the current ScanService document, nor would I expect
    a DeleteService request to be an operation in a typical implementation. It
    is not clear that much would be gained by explicitly adding it to the
    ScanService document, although it might be useful for other services,
    particularly if you have a system where there may be multiple instantiations
    of a given service. I would leave that for general discussion.

    Finally, my comments on the Scan Service Theory of Operation were intended
    to address areas that I found confusing and areas that appeared inconsistent
    with other parts of the document. I took such issues to be a result of not
    updating the chapter as the rest of the document matured. It was not my
    intent to change or embellish the model.

    I see the "General MFD Service" document as a less rigorous overview,
    dealing with general concepts applicable to models of multiple Services and
    with how the various Services fit within a Multifunction Device. Certainly,
    some of these issues will come up when we discuss my first draft (which I
    had better get cracking on).

    Thanks,

    Bill Wagner

    -----Original Message-----
    From: Ira McDonald [mailto:blueroofmusic@gmail.com]
    Sent: Monday, February 02, 2009 5:32 PM
    To: William A Wagner; Ira McDonald
    Cc: mfd@pwg.org
    Subject: Re: MFD> Scan Service Sectionr 10

    Hi Bill,

    I hope you're not suggesting we delete the state
    tables?

    We could certainly *bend* the operations (e.g., to let
    StartupScanService be an operation received by a
    ScanService in Initial / Down state).

    But in the real world of WSDL bindings, that won't work!

    A service can only receive an incoming WSDL (SOAP)
    request when it's ALREADY instantiated, addressable,
    and at least Down.

    I believe that our MFD Model should have a first-class
    System object that receives StartupService (with a param
    for what type of service) and DeleteService (to really
    remove a Down service instance).

    I do NOT see the problem with references to ISO 10175
    Part 1 (Printing Ops) and Part 3 (Admin Ops). This is the
    underpinning of most all IPP attributes and operations and
    therefore of the PWG Semantic Model v1.0 itself.

    Cheers,
    - Ira

    Ira McDonald (Musician / Software Architect)
    Chair - Linux Foundation Open Printing WG
    Blue Roof Music/High North Inc
    email: blueroofmusic@gmail.com
    winter:
      579 Park Place Saline, MI 48176
      734-944-0094
    summer:
      PO Box 221 Grand Marais, MI 49839
      906-494-2434

    On Mon, Feb 2, 2009 at 1:31 PM, William A Wagner <wamwagner@comcast.net>
    wrote:
    > Ira,
    >
    > Sorry, I am not following you. What I was attempting, in what little way I
    > can, is to have the Scan Service document at least consistent within
    itself.
    > If my attempt has been unsuccessful, I will most willingly drop the
    > suggested changes.
    >
    > I agree that it is good to also have the document consistent with related
    > documents; but one cannot assume that readers are all familiar with the
    > various other documents that you reference, at least not to the extent
    that
    > terms and concepts in those documents are common knowledge and need not be
    > defined (at least by reference.. but that can get cumbersome)
    >
    > The term "System" as a formal object is not defined in the Scan Service
    > document. The word system is appears to be used in a general sense,
    although
    > perhaps this is just my interpretation. Indeed, I wonder if these uses of
    > the word, although they may be derived from other definitive
    specifications,
    > make sense.
    >
    > 1831 Pending - the job has been accepted by the system and is
    > awaiting system resources before it can start processing
    >
    > 2276 Aborted - The Document has been aborted by the system, ...
    >
    > Neither does the Scan Service document use the term Startup Event (except
    > cryptically in the State table) although it does use Startup() in the
    State
    > Diagram and define StartupScanService as an (optional) operation. (How is
    > the service "created" if there is no Startup operation?)
    >
    > I find your explanation that "Startup *event* (not operation) arrives at
    the
    > Service object in Initial phase / Unknown state..." confusing considering
    > your statement that it is the "StartupScanService operation... sent to a
    > System (NOT a ScanService) that creates a new instance of a ScanService in
    > the Initial phase..." If StartupScanService creates a service, how can the
    > Startup *event* arrive at the Service...unless of course the Startup event
    > is a secondary result of the Startup operation, occurring after the
    > operation has already created the service. Or perhaps the Startup event is
    > completely independent from the Startup operation?
    >
    > But I really question whether all this is germane. I think it is important
    > for the specification define the external interfaces and how the service
    (or
    > system) responds to them. I think it desirable that the specification not
    be
    > self inconsistent or unnecessarily confusing. I think that attempts to
    > define the internal implementation beyond what is necessary to
    characterize
    > black-box behaiour are unnecessary, will usually be ignored, and may cause
    > the document to be ignored. This of course is just my opinion.
    >
    > Thanks,
    >
    > Bill Wagner
    >
    >
    >
    > -----Original Message-----
    > From: Ira McDonald [mailto:blueroofmusic@gmail.com]
    > Sent: Monday, February 02, 2009 10:51 AM
    > To: William A Wagner; Ira McDonald
    > Cc: mfd@pwg.org
    > Subject: Re: MFD> Scan Service Sectionr 10
    >
    > Hi Bill,
    >
    > The System object is defined in WIMS and also in SM/2.0 schema
    > and has been for years.
    >
    > Miracle happens is bad design - so MFD services that are created
    > AFTER the device is installed MUST be based on operations that
    > are targeted to the System object (same semantics as a Server
    > object in ISO 10175-Part3).
    >
    > My Note (1) says that Startup *event* (not operation) arrives at the
    > Service object in Initial phase / Unknown state, which exactly follows
    > the state transition tables and notes in ISO 10175-Part3.
    >
    > The alternative is to break with DPA and show that a Service object
    > comes into existence in the Initial phase / Down state (and receives
    > the Startup event). But that transition from Unknown to Down is the
    > one (in DPA) that does the one-time initialization of data structures.
    >
    > Cheers,
    > - Ira
    >
    > Ira McDonald (Musician / Software Architect)
    > Chair - Linux Foundation Open Printing WG
    > Blue Roof Music/High North Inc
    > email: blueroofmusic@gmail.com
    > winter:
    > 579 Park Place Saline, MI 48176
    > 734-944-0094
    > summer:
    > PO Box 221 Grand Marais, MI 49839
    > 906-494-2434
    >
    >
    >
    > On Mon, Feb 2, 2009 at 12:39 AM, William A Wagner <wamwagner@comcast.net>
    > wrote:
    >> Ira,
    >>
    >> 1. Yes, you had made the point before that StartupScanService was sent to
    > a
    >> (undefined?) system, not to the service that is being started. However,
    > the
    >> detailed state diagram (Fig 27) indicates that "Startup" takes the
    service
    >> from Down to Idle. There is no indication of what takes service from
    > Unknown
    >> to Down. From a practical state, I questioned the Unknown to Down state
    >> transition prior to going to Idle. To address StartupScanService,
    perhaps
    >> line 5 should read: "On creation by a StartupScanService request, the
    Scan
    >> Service enters its Initial phase..."? Would acceptable wording on Line 7
    >> be: "After successful initialization, the Scan enters the Online
    > state..."
    >>
    >> Pete's 22 Jan version includes RestartScanService so I expect that that
    >> should be mentioned.
    >>
    >> 2. I understand your distinction, but the detailed state diagram shows
    > that
    >> pause() and C.Critial effect the transition to Stopped. How about if we
    > keep
    >> it simple here in the text and just say "...either a Critical event is
    >> generated" and avoid getting into the specific notation of the detailed
    >> state discussion?
    >>
    >> Thanks,
    >>
    >> Bill Wagner
    >>
    >> -----Original Message-----
    >> From: owner-mfd@pwg.org [mailto:owner-mfd@pwg.org] On Behalf Of Ira
    > McDonald
    >> Sent: Sunday, February 01, 2009 10:28 PM
    >> To: William A Wagner; Ira McDonald
    >> Cc: mfd@pwg.org
    >> Subject: Re: MFD> Scan Service Sectionr 10
    >>
    >> Hi Bill and Pete.
    >>
    >> Bill - I like all of your new text.
    >>
    >> However, there are two serious problems in existing text:
    >>
    >> (1) Second paragraph at line line 5 of page 2 is just wrong
    >>
    >> It is a StartupScanService operation (spelled that way) sent
    >> to a System (NOT a ScanService) that creates a new instance
    >> of a ScanService in the Initial phase, causes self-test, and finally
    >> transition to Online phase / Idle state. The ScanService itself
    >> does NOT perform a start-up operation (line 7). It is handling
    >> the single E.startup *event* sent to it by the System (while in
    >> in the Initial phase / Unknown state).
    >>
    >> If we keep it, a RestartScanService operation could be sent
    >> to a ScanService (to recover from a Shutdown to Offline
    >> phase / Down state). See the notes on lines 1628 to 1639
    >> on pages 66 and 67 of lcrc-mfdscanmodel10-20090119.pdf
    >>
    >>
    >> (2) Recurring problem of reading the terms in state tables
    >>
    >> The notation key in the Scan Service spec for the state table
    >> is at line 1618 page 66 in lcrc-mfdscanmodel10-20090119.pdf
    >>
    >> For example at line 12 in page 2 of your draft, we see:
    >>
    >> "...either a C.Critical event is generated"
    >>
    >> The expression "C.Critical" means a *passive* Condition (C)
    >> (i.e., a ScanService.StateReasons value) is TRUE that a Critical
    >> alert is now pending. While, the expression "~C.Critical" means
    >> that any NOT (~) Critical Condition is now pending.
    >>
    >> The expression "E.Critical" means that an *active* Event (E)
    >> that is Critical has just occurred. Conversely "~E.Critical" means
    >> that any non-Critical (i.e., warning) event has just occurred.
    >>
    >> So "C.Critical event" is confused.
    >>
    >> Cheers,
    >> - Ira
    >>
    >> Ira McDonald (Musician / Software Architect)
    >> Chair - Linux Foundation Open Printing WG
    >> Blue Roof Music/High North Inc
    >> email: blueroofmusic@gmail.com
    >> winter:
    >> 579 Park Place Saline, MI 48176
    >> 734-944-0094
    >> summer:
    >> PO Box 221 Grand Marais, MI 49839
    >> 906-494-2434
    >>
    >>
    >>
    >> On Fri, Jan 30, 2009 at 4:26 PM, William A Wagner <wamwagner@comcast.net>
    >> wrote:
    >>> Considering the decisions at yesterday's conference call with respect to
    >>> "submitting a job", I modified the proposed rework of Section 10 of the
    >> Scan
    >>> Service document. This rework (only in markup) is posted as
    >>> ftp://ftp.pwg.org/pub/pwg/mfd/white/ScanServiceTheoryOfOp-revB.pdf.
    >>>
    >>>
    >>>
    >>> Thanks,
    >>>
    >>>
    >>>
    >>> Bill Wagner
    >>>
    >>>
    >>>
    >>> From: owner-mfd@pwg.org [mailto:owner-mfd@pwg.org] On Behalf Of Zehler,
    >>> Peter
    >>> Sent: Thursday, January 29, 2009 1:38 PM
    >>> To: mfd@pwg.org
    >>> Subject: MFD> Update to Agenda for MFD Teleconference, Thursday 1/29
    3:00
    >>> EDT
    >>>
    >>>
    >>>
    >>>
    >>>
    >>> There will be an MFD conference call at 3:00 PM EDT (12:00 PM PDT) this
    >>> Thursday. The meeting is held in accord with the PWG Intellectual
    >> Property
    >>> Policy.
    >>>
    >>>
    >>>
    >>> Note the NEW Teleconference number and access code are now used.
    >>>
    >>> Please contact me if you do not have the new number and pass code.
    >>>
    >>>
    >>>
    >>> Agenda:
    >>>
    >>> 1. Identify Minute Taker
    >>>
    >>> 2. Approval of minutes from last teleconference
    >>>
    >>>
    >> <ftp://ftp.pwg.org/pub/pwg/mfd/minutes/pwg-mfd-minutes-20090115.pdf>
    >>>
    >>> 3. Agenda bashing
    >>>
    >>> 4. Discuss syntax of JobPhoneNumber on line 2182 of Scan specification
    >>>
    >>> 5. Discuss open ended REQUIREMENT governed by a third party (End User)
    >>> policy on line 2788-2790 of Scan specification
    >>>
    >>> 6. Discuss Bill's comments on in Resource Service
    >>>
    >>>
    >>>
    >>
    >
    <ftp://ftp.pwg.org/pub/pwg/mfd/white/nancy-Proposed-Resolution-for-Bill-W-co
    >> mments-for-Resource-Service-20090127.pdf>
    >>>
    >>> b) Discussion of Testing State, transition in and out, and method
    > of
    >>> transition Part of both Resource and Scan Service discussion)
    >>>
    >>> 7. Discussion on Scan Service State and proposed change to section 10 of
    >> the
    >>> specification
    >>>
    >>> a) Chose between the existing text, proposed text or arrive at
    some
    >>> other consensus.
    >>>
    >>> Existing text is section 10
    >>> <ftp://ftp.pwg.org/pub/pwg/mfd/wd/lcrc-mfdscanmodel10-20090122.pdf>
    >>>
    >>> Proposed change is available at
    >>> <ftp://ftp.pwg.org/pub/pwg/mfd/white/ScanServiceTheoryOfOp.pdf>
    >>>
    >>> 8. Discuss any comments on the Resource Service interim draft.
    Objective
    >> is
    >>> to move to the Last Call version for review at the Face to Face.
    >>>
    >>>
    >> <ftp://ftp.pwg.org/pub/pwg/mfd/wd/wd-mfdresourcemodel10-20090115.pdf>
    >>>
    >>> 9. Next steps
    >>>
    >>>
    >>>
    >>> Click Here to Join Live Meeting
    >>>
    >>
    >
    <https://www.livemeeting.com/cc/xerox/join?id=PWG_MFD&role=attend&pw=PQ%25%3
    >> EFj5sN>
    >>>
    >>>
    >>>
    >>>
    >>>
    >>>
    >>>
    >>>
    >>>
    >>>
    >>>
    >>>
    >>> Peter Zehler
    >>>
    >>> Xerox Research Center Webster
    >>> Email: Peter.Zehler@Xerox.com
    >>> Voice: (585) 265-8755
    >>> FAX: (585) 265-7441
    >>> US Mail: Peter Zehler
    >>> Xerox Corp.
    >>> 800 Phillips Rd.
    >>> M/S 128-25E
    >>> Webster NY, 14580-9701
    >>>
    >>>
    >>
    >>
    >
    >



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