IPP Mail Archive: Re: IPP> notification methods

IPP Mail Archive: Re: IPP> notification methods

Re: IPP> notification methods

From: kugler@us.ibm.com
Date: Fri Aug 04 2000 - 15:09:41 EDT

  • Next message: kugler@us.ibm.com: "Re: IPP> notification methods"

    Jay-

    I'm using the word "server" in its classic TCP/IP sense. From
    Internetworking with Tcp/ip, Volume 1, by Comer, Douglas E:

         The term SERVER applies to any program that offers a service that can
    be reached over the network.
    Servers accept requests that arrive over the network, perform their
    service, and return the result to the requester...

         A server starts execution before interaction begins and (usually)
    continues to accept requests and send responses without ever terminating. A
    client is any program that makes a request and awaits a response...

         A server waits for requests at a well-known port that has been
    reserved for the service it offers. A client allocates an arbitrary,
    unused, nonreserved port for its communication...

         Servers are usually more difficult to build than clients because, even
    though they can be implemented with application level programs, servers
    must enforce all the access and protection policies of the computer system
    on which they run, and they must protect themselves against all possible
    errors.

    The INDP "user agent" (possibly part of an IPP "client" application) is
    actually a HTTP/TCP/IP server.

         -Carl

    Jay Martin <jkm@underscore.com> on 08/04/2000 12:15:16 PM

    Please respond to jkm@underscore.com

    To: Carl Kugler/Boulder/IBM@IBMUS
    cc: ipp@pwg.org
    Subject: Re: IPP> notification methods

    Carl,

    Would it be possible for you to *briefly* explain to the list
    why INDP requires "a server per user"? Some of us are a bit
    confused by this. Perhaps the definition of "server" varies
    amongst some of us. Thanks,

         ...jay

    kugler@us.ibm.com wrote:
    >
    > There is a huge PRACTICAL difference between mailto vs. indp: indp
    > requires a server per user, mailto only requires a client. There is a
    > great difference in cost, complexity, resource consumption, and security
    > considerations between running a client on the Internet and deploying a
    > server on the Internet. Most Internet servers are used by many users, so
    > the cost is affordable. A server per user just won't scale to the
    > Internet.
    >
    > -Carl
    >
    > --- In ipp@egroups.com, don@l... wrote:
    > > The real difference between the use of mailto versus INDP is that
    mailto
    > is for
    > > a receipient who does not have an IPP/INDP enabled client or does not
    > have it
    > > running at the time the notification is to be received.
    > >
    > > **********************************************
    > > * Don Wright don@l... *
    > > * Chair, Printer Working Group *
    > > * Chair, IEEE MSC *
    > > * *
    > > * Director, Strategic & Technical Alliances *
    > > * Lexmark International *
    > > * 740 New Circle Rd *
    > > * Lexington, Ky 40550 *
    > > * 859-232-4808 (phone) 859-232-6740 (fax) *
    > > * (Former area code until 10/1 was 606) *
    > > **********************************************
    > >
    > >
    > >
    > > harryl%us.ibm.com@i... on 07/26/2000 10:54:23 AM
    > >
    > > To: Don_Wright/Lex/Lexmark@LEXMARK
    > > cc: ipp%pwg.org@i...,
    > > pmoore%peerless.com@i... (bcc: Don Wright/Lex/Lexmark)
    > > Subject: Re: IPP> notification methods
    > >
    > >
    > >
    > >
    > >
    > >
    > > I accept that INDP may "work" in the Internet if properly configured.
    > But,
    > > in this case, you wouldn't necessarily need to mandate mailto for human
    > > readable. So either association (mail/human - indp/machine OR
    > mail/inter
    > > - indp/intra) is equally flawed.
    > >
    > > Then... the only thing certain is that mailto is NOT intended for
    machine
    > > readable. Why don't we just state that?
    > >
    > > Peter Z. has a suggestion for helping to determine what is supported.
    > > > a notification... sent out at INDP registration... (that) allows a...
    > > > recipient to determine if the infrastructure supports INDP...
    > >
    > > Harry Lewis
    > > IBM Printing Systems
    > >
    > >
    > >
    > >
    > > don@l...
    > > Sent by: owner-ipp@p...
    > > 07/26/2000 05:01 AM
    > >
    > >
    > > To: Harry Lewis/Boulder/IBM@IBMUS
    > > cc: pmoore@p..., ipp@p...
    > > Subject: Re: IPP> notification methods
    > >
    > >
    > > I fail to see the reason to ASSUME that every implementation of IPP
    > > NOTIFICATION
    > > will occur behind a firewall that is NOT configured to allow INDP
    > > notifications
    > > to pass through it. Any attempt to associate "mailto" or "indp"
    > > EXCLUSIVELY
    > > with either INTERnets or INTRAnets is flawed. If we would have used
    this
    > > argument for IPP in the beginning we would have made statements like:
    > >
    > > 1. If a device is configured to print across the Internet it IS OUT OF
    > > LUCK.
    > > 2. If a device is configured to print in the context of an Intranet it
    > > MUST
    > > support IPP.
    > >
    > > Let's separate the issue of the INTERNET vs INTRANET context of these
    > > delivery
    > > services. When a customer decides they want these services, they will
    > > configure
    > > their firewalls (if present) to make it happen.
    > >
    > > **********************************************
    > > * Don Wright don@l... *
    > > * Chair, Printer Working Group *
    > > * Chair, IEEE MSC *
    > > * *
    > > * Director, Strategic & Technical Alliances *
    > > * Lexmark International *
    > > * 740 New Circle Rd *
    > > * Lexington, Ky 40550 *
    > > * 859-232-4808 (phone) 859-232-6740 (fax) *
    > > * (Former area code until 10/1 was 606) *
    > > **********************************************
    > >
    > >
    > >
    > >
    > >
    > >
    > > harryl%us.ibm.com@i... on 07/26/2000 01:00:41 AM
    > >
    > > To: pmoore%peerless.com@i...
    > > cc: ipp%pwg.org@i... (bcc: Don Wright/Lex/Lexmark)
    > > Subject: Re: IPP> notification methods
    > >
    > >
    > >
    > >
    > >
    > >
    > > I feel a more accurate way of looking at it is:
    > >
    > > 1. If a device is configured to provide event notification across the
    > > Internet it MUST support mailto
    > > 2. If a device is configured to provide event notification in the
    context
    > > of an Intranet it SHOULD support INDP
    > >
    > > We could live with the proposal to bind human/mail vs. machine/indp.
    > > However, this ignores the fact that INDP also handles human readable.
    > >
    > > Harry Lewis
    > > IBM Printing Systems
    > >
    > >
    > >
    > >
    > > pmoore@p...
    > > Sent by: owner-ipp@p...
    > > 07/20/2000 09:31 AM
    > >
    > >
    > > To: ipp@p...
    > > cc:
    > > Subject: IPP> notification methods
    > >
    > >
    > > Following the SF meeting I would like to formally propose the
    following.
    > >
    > > 1. If a device wants to expose human readable events then it MUST
    support
    > > the
    > > mailto method
    > >
    > > 2. If a device wants to expose machine readable events then it MUST
    > > support the
    > > INDP method
    > >
    > > But we do not UNCONDITIONALLY require either.
    > >
    > > (Now dons flame-proof clothing and awaits flaming)



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