IPP Mail Archive: IPP> MOD - Issue 2: How can client force authentication, i.e., identi

IPP Mail Archive: IPP> MOD - Issue 2: How can client force authentication, i.e., identi

IPP> MOD - Issue 2: How can client force authentication, i.e., identi

Hastings, Tom N (hastings@cp10.es.xerox.com)
Tue, 23 Mar 1999 17:24:14 -0800

Here is the third issue from the Bake Off that has several possible
alternatives. This issue has also had a lot of email discussion since the
Bake Off. We list some additional alternatives to adding a new operation.
What do people think of the alternatives?

Tom

2) ISSUE: How can client force identified mode?

If an IPP Printer supports both authenticated and unauthenticated
access, there is no way for a client to force itself to be
authenticated, i.e., be in identified mode, since it is the server that
forces authentication by issuing a challenge to the client. It is
very useful for a client to be able to get into identified mode as soon
as possible. Today you have to wait to be challenged by the server,
which may never happen -- or happens at an unpredictable time. The
security conformance requires that the authentication for operations be
the same for all operations. So for authenticated Cancel-Job, the
Print-Job has to be authenticated as well. We would like to add another
operation that forces the server to generate a 401 authentication
challenge which the client would submit before submitting the print job
in the first place. Unless somebody has a different solution
(Microsoft)

Possible alternatives:

1.Add the operation as an OPTIONAL operation to IPP/1.0 and IPP/1.1
that forces the IPP object to issue a challenge to the client.

2.Use two URLs for the same IPP Printer object, one requires
authentication and the IPP server always issues a challenge and the
other never does. So the client that wants to be authenticated
submits requests to the URL that requires authentication. ISSUE: How
does the client discover which URL to use, since "uri-security-
supported" is about security, not authentication?

3.Use two IPP Printer objects that fan-in to the same device. One IPP
Printer object requires authentication and always issues the
challenge and the other never does. ISSUE: How does the client
discover which IPP Printer to use for authenticated access?

4.Request that the HTTP WG add some kind of header that allows the
client to request that the HTTP server issue a challenge. ISSUE: It
is unlikely that the HTTP group would do such a thing, since it is
not needed for the usual use of HTTP which is to access documents on
a server.