RE: WIMS> RE: CIM object requirement for WS-Management

From: nchen@okidata.com
Date: Fri May 16 2008 - 09:58:57 EDT

  • Next message: William A Wagner: "RE: WIMS> RE: CIM object requirement for WS-Management"

    Hi Bill,

    Thanks for sharing your observations.

    Based on your and Rick's rationales, it's important for every imaging
    device vendor to have a CIM converter between a SNMP agent and WS-Man to
    ease SNMP to WS-Management migration path.

    Since Rick is building such a CIM proxy/server just for this purpose, I
    think we should consider to make it available to all PWG members. We
    should call members to either contribute their engineering resource or
    provide monitary help for hiring appropriate resources to help build the
    required software components. This will greatly benefit all PWG members
    down the road. Let's make it happen!

    -Nancy

    "William A Wagner" <wamwagner@comcast.net>
    05/15/2008 05:41 PM

    To
    <Richard_Landau@Dell.com>, <nchen@okidata.com>
    cc
    <wims@pwg.org>
    Subject
    RE: WIMS> RE: CIM object requirement for WS-Management

    Thank you, Rick, for that complete statement which pretty much states
    the
    basis for the WIMS/CIM activity. I would make a few more observations:

    - Even if/when WS-Man becomes more popularly used, SNMP is not
    going away for a long time and there will be a prolonged period of
    supporting both management protocols. By basing the CIM Print management
    elements on well established and implemented MIB objects, the CIM Printer
    effort :

    o Allows early support of printer management via WS-Man by using
    software
    or network appliance SNMP to WS-Man converters, so that printers that just
    support SNMP can still be monitored via WS-Man.

    o Allows use of a common management information base in the printer that
    the two management protocols can both draw upon.

    - Although this approach allows monitoring via WS-Man pretty much
    to the same degree as with the standard Printer MIB sets, at this point it
    does not address the additional features of modern printers that are not
    covered in the traditional MIBs.

    o This deficiency will be alleviated somewhat by the current activity to
    render the Imaging System Counter MIB objects in CIM format

    o Hopefully, there will be additional PWG work to recast service and job
    elements in IPP and in other MIBs into CIM format

    o We envision an effort to eventually enrich the CIM imaging libraries
    with additional MFD oriented elements

    Of course, this all takes work in selecting and defining management
    elements, in formatting the information appropriately, and in going
    through
    the standardization steps. Rick and Ira have beaten something of a path to
    follow and have offered to provide guidance to those who would continue
    this
    effort. The objective would be to provide adequate standard management
    capability for imaging devices via WS-Man, avoiding the Balkanizing that
    has
    occurred with the plethora of private MIBs. In the last analysis, this
    would save significant effort both for manufacturers and management
    providers, and ultimately would benefit the customers as well (perhaps
    encouraging more use of imaging systems).

    Bill Wagner

    From: owner-wims@pwg.org [mailto:owner-wims@pwg.org] On Behalf Of
    Richard_Landau@Dell.com
    Sent: Thursday, May 15, 2008 1:55 PM
    To: nchen@okidata.com
    Cc: wims@pwg.org
    Subject: WIMS> RE: CIM object requirement for WS-Management

    Nancy, I'm sorry that I wasn't clearer about the structure and future of
    web
    service management in the printer space. Thank you for the question.
    Clarification follows, I hope. I think this deserves a real answer, not
    just yes-no. And I think a lot of people need to hear the answer. I hope
    you don't mind my sending this reply to a broader audience.

    - WS-Management is not restricted to transferring CIM-based objects. The
    WS-Man protocol can be used with any sort of objects. In this sense, it
    is
    like SNMP without MIBs. WS-Man includes Get, Put, Enumerate (and so
    forth)
    just as SNMP includes Get, Set, GetNext (and so forth).

    - A protocol is not sufficient to manage a device. You still have to
    define
    the management data objects that are to be manipulated by the protocol
    operations. For SNMP, one defines MIBs, lots of them, to specify the
    syntax
    and semantics of the data to be manipulated. For WS-Man, the only public,
    standard definitions so far are CIM objects.

    - DMTF (dmtf.org) publishes the WS-Man protocol standard as its document
    DSP0226. It also publishes the WS-Man CIM Binding spec, which describes
    how
    CIM objects are to be named and manipulated using WS-Man, as DSP0227. And
    the XML representation of CIM objects for use by web services is described
    in DSP0230. The entire CIM schema is also published by DMTF and updated
    three times per year.

    - PWG has just invested considerable effort in defining the CIM classes
    for
    a Printer device to match the model of the Printer MIB and the Semantic
    Model. The CIM schema v2.19 now contains about fifteen classes and a
    hundred properties that very closely parallel the Printer MIB. So,
    theoretically, it would now be possible to manage a printer using a modern
    web service, WS-Management.

    - As a proof of the mapping from SNMP to CIM schema, I am building a
    prototype of a proxy provider for a CIM server. This will take SNMP data
    from a network printer and re-publish it in a CIM Object Manager ("CIMOM,"
    such as WMI on Windows) using these new printer-related classes.

    - If someone wants to invent another mapping of the industry-standard
    printer management data to some other data model, he/she is free to do
    that.
    However, the result won't be any smaller or simpler than the one that was
    in
    the Printer MIB -- and is now in the CIM schema. Sure, it's possible, but
    why bother? We already invested the man-year or two necessary to define
    that data in a published standard. Any sensible implementer will simply
    use
    what is available.

    - Many of us are convinced that web services will become popular
    management
    protocols, and over time will become the dominant protocols. If something
    is not manageable by a web service protocol, at some point in the future,
    on
    some set of corporate networks, it simply won't be manageable at all.

    - Overhead? Sure, everything has overhead. The SNMP agent in a printer
    has
    overhead, and manufacturers complained about that expense when it was
    first
    implemented. The HTTP web service in a printer has overhead, and
    manufacturers complained when it was first implemented. So, too, the
    WS-Man
    service management agent in a future printer will have overhead, and we
    will
    complain about that. But if we want a device to be manageable in
    corporate
    and educational networks, we have no choice. Customers insist on
    out-of-band management as a feature of all network devices.

    - I will point out that, as of late this year, every new business desktop
    and laptop computer system will have a complete, WS-Man-based,
    out-of-band,
    management agent, using (dozens of) CIM classes to transfer data. Look
    for
    "DASH" in the feature list. The major vendors will be using chips
    developed
    by a number of companies, including all the major NIC and management
    controller companies, in any new system that requires remote management.
    The overhead for this agent is small, and largely in silicon.

    So, to answer your question, No, WS-Management is not *required* to use
    CIM
    objects, but it *can* use CIM objects. And CIM objects represent a very
    rich and growing set of management objects for computer systems and
    peripherals. If one wants to include web service management in a device,
    the WS-Management and CIM schema standards are already available.

    rick

    ----------------------
    Richard_Landau(at)dell(dot)com, Stds & System Mgt Architecture, CTO Office
    +1-512-728-9023, One Dell Way, RR5-3, MS RR5-09, Round Rock, TX 78682

    _____

    From: nchen@okidata.com [mailto:nchen@okidata.com]
    Sent: Thursday, May 15, 2008 09:49
    To: Landau, Richard
    Subject: CIM object requirement for WS-Management

    Hi Rick,

    I remember at the beginning of WIMS-CIM alignment project, you mentioned
    that in the future WS-Managet will only accept CIM objects.

    Is this still true? I don't see this compliance statement in WS-Management
    spec, neither the claim at DMTF CIM web site. Would you please verify this
    remains true? If so, do a device wishing to be managed by WS-Management
    need
    to embedded their management data in CIM objects within the device? I see
    a
    lot of overhead in this.

    -Nancy
    ------------------------------------------------
    Nancy Chen
    Principal Engineer
    Solutions and Technology
    Oki Data
    2000 Biships Gate Blvd.
    Mt. Laurel, NJ 08054
    Phone: (856) 222-7006
    Emal: nchen@okidata.com



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