IPP Mail Archive: Re: IPP> PRO - Use of special port for IPP

Re: IPP> PRO - Use of special port for IPP

Jay Martin (jkm@underscore.com)
Fri, 26 Sep 1997 21:11:34 -0400

Why can't we have it both ways? That is, assume the standard default
port 80 can be used, but also specify a "standard alternative port"?

...jay

Carl-Uno Manros wrote:
>
> At 12:28 PM 9/23/97 PDT, papowell@astart.com wrote:
> >> SECURITY
> >
> >
> >> There are reserved port numbers for TLS & SSL on HTTP (port
> >> 443)
> >
> >> TLS is backwards compatible with SSL3. Actually TLS is
> >> SSL3.1 The TLS I-D describes how to support SSL3
> >> interoperability.
> >
> >> The group then discussed wording choices for stating the
> >> security protocol requirements (SSL3, TLS, etc.) There were
> >> four wording alternatives explored:
> >
> >> 1) IPP Client/Servers must implement TLS with SSL3
> >> compatibility
> >> 2) IPP Client/Servers shall be interoperable with a TLS
> >> communicant
> >> 3) IPP Client/Servers must be TLS compliant.
> >> 4) #2 above plus "with SSL3 backward compatibility"
> >
> >> Decision: #1 with some section talking about a transition to
> >> TLS.
> >
> >I will note carefully that this closely follows the model of having
> >different ports for different protocols. Note that TSL/SSL actually are
> >HTTP over TSL and HTTP over SSL. We are similarly doing IPP over HTTP.
> >
> >Should this be the same port or a different port?
> >
> >Patrick
> >
>
> Patrick,
>
> Our decision not to pursue a separate port for IPP in the standard was that
> there seems to be as many reasons for as against using a separate port.
> E.g. Netscape has suggested using a separate port, Microsoft has suggested
> using the standard HTTP port, so even among those heavyweights there is no
> agreement.
>
> If it turns out that a particular domain or vendor wants to use a special
> port different from the normal HTTP port, it can be included in the Printer
> URIs for those IPP printers. And as you notice from the notes above, in
> cases where we want to run IPP over a secure connection such as TLS, the
> security protocol dictates which port to use, so to define a special port
> for IPP makes no sense for such scenarios.
>
> Regards,
>
> Carl-Uno
> Carl-Uno Manros
> Principal Engineer - Advanced Printing Standards - Xerox Corporation
> 701 S. Aviation Blvd., El Segundo, CA, M/S: ESAE-231
> Phone +1-310-333 8273, Fax +1-310-333 5514
> Email: manros@cp10.es.xerox.com