Like I said before - why do we have to mandate one or more methods. THe only
reason for mandating things is so that a client can be guaranteed that a service
will exist (I.e all IPP client can safely be built using print-job because it
MUSTbe there).
Since notifications are a) optional and b) not always going to work (because of
firewall issues, or other reasons - I might be at a site that doesnt have an
SMTP infrastructure - unlikely but possible) then a client can never make that
assumption. A client builder must always be prepared to deal with the fact that
their favorite notification method is not available. Therefore the mandating of
methods is useless.
I think what various people are really saying is 'these are the two no-brainer
methods(mail & INDP) that we need to get standardized and baked-off' - I agree
with them.
don at lexmark.com on 06/22/2000 01:16:34 PM
To: kugler at us.ibm.com
cc: ipp at pwg.org (bcc: Paul Moore/AUCO/US)
Subject: Re: IPP> TES: Mandatory IPP notification agreement
Just because there are cases where a machine can't get notifications does not
mean we should not standardize it. By making it mandatory, developers of
products must support it. It doesn't mean that everyone must use it. (BTW: I
am also in favor of making e-mail mandatory).
**********************************************
* Don Wright don at lexmark.com *
* 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) *
**********************************************
kugler%us.ibm.com at interlock.lexmark.com on 06/22/2000 04:13:36 PM
To: Don_Wright/Lex/Lexmark at LEXMARK
cc: (bcc: Don Wright/Lex/Lexmark)
Subject: Re: IPP> TES: Mandatory IPP notification agreement
Many firewalls allow you to connect many more machines to the Internet than
you have IP addresses for. The addresses behind the firewall may be
private, unregistered addresses, not globally routable, not globally
unique.
-Carl
don at lexmark.com on 06/22/2000 01:40:16 PM
To: Carl Kugler/Boulder/IBM at IBMUS
cc:
Subject: Re: IPP> TES: Mandatory IPP notification agreement
Firewalls are configurable.
Don
kugler%us.ibm.com at interlock.lexmark.com on 06/22/2000 03:33:16 PM
To: Don_Wright/Lex/Lexmark at LEXMARK
cc: ipp%pwg.org at interlock.lexmark.com (bcc: Don Wright/Lex/Lexmark)
Subject: Re: IPP> TES: Mandatory IPP notification agreement
Will go through OUTBOUND from a Printer INSIDE to a client OUTSIDE. But
what if the CLIENT is behind a firewall?
-Carl
don at lexmark.com on 06/22/2000 12:04:27 PM
To: Carl Kugler/Boulder/IBM at IBMUS
cc: ipp at pwg.org
Subject: Re: IPP> TES: Mandatory IPP notification agreement
In the matter of INDP and firewalls, INDP WILL go through a properly
configured
firewall. It won't go through one that blocks on whatever port we are
assigned.
Let's be accurate.
**********************************************
* Don Wright don at lexmark.com *
* 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) *
**********************************************
kugler%us.ibm.com at interlock.lexmark.com on 06/21/2000 06:08:52 PM
To: ipp%pwg.org at interlock.lexmark.com
cc: (bcc: Don Wright/Lex/Lexmark)
Subject: Re: IPP> TES: Mandatory IPP notification agreement
[Added subject line and this P.S.:]
henrik.holst at i... wrote:
>> Well it was my understanding that we didn't agree on a mandatory method.
> And the INDP method
> won't go through a firewall, so if you are searching for a mandatory
method
> I would say MAILTO.
I agree, INDP won't go through firewalls.
---------------------- Forwarded by Carl Kugler/Boulder/IBM on 06/21/2000
04:07 PM ---------------------------
From: Carl Kugler on 06/21/2000 03:39 PM
To: ipp at pwg.org
cc:
From: Carl Kugler/Boulder/IBM at IBMUS
Subject:
"Zehler, Peter" <Peter.Zehler at u...> wrote:
..
> My preference is that INDP be mandated. I feel that programmatic
> notification is critical to the development of robust IPP applications.
One
> of those applications would be QUALDOCS. In the definition of IPP, and
its
> associated notification mechanism, I am concerned primarily with client
> /server communications. End user notification, while useful, is not my
> primary objective. It is true that infrastructure will have to be
> configured to allow this traffic to pass. The same is true of outbound
IPP
> requests. I imagine that most of our printers will also implement mailto.
I
> have no objections to allowing both, but I think only one should be
> mandated.
>..
Actually, in many cases the infrastructure does not have to be configured
to allow outbound IPP requests. I've always been able to connect to IPP
Printers on the Internet with an IPP client here inside the IBM firewall.
(In fact, I remember connecting my client to your Printer a few years ago!)
We run a SOCKS Internet gateway here, and I can make a TCP connection to
any host:port on the Internet.
"McDonald, Ira" <imcdonald at s...> wrote:
..
> Lastly, Peter you jumped from port filtering by firewalls
> to MIME type filtering - but the latter requires that the
> firewall have an Application Layer Gateway (ALG) to figure
> out the protocol and THEN to find the MIME type inside the
> protocol envelope.
>> Personally, I agree with Henrik about selecting email as
> the IPP mandatory notification method.
>
Most firewalls allow insiders to make outbound connections (perhaps
indirectly), but prevent outsiders from making inbound connections. Very
few corporate firewall administrators would be willing to simply open a
port and allow anybody to make inbound connections to arbitrary addresses
inside the firewall. Here at IBM, making an inbound connection requires
full-blown authentication, encryption, one-time passwords, etc. (by
strictly enforced corporate policy). We use Aventail for this. Also, in
many cases, machines inside a firewall are simply not addressable from
outside, due to network address translation (NAT), IP Masquerading, Windows
connection sharing, etc. You'd need a really sophisticated
application-level gateway to deal with these issues.
-Carl