IPP Mail Archive: IPP> ADM - Minutes from PWG IPP Phone Conference - 980107

IPP> ADM - Minutes from PWG IPP Phone Conference - 980107

Carl-Uno Manros (cmanros@cp10.es.xerox.com)
Wed, 7 Jan 1998 17:06:46 PST

Minutes from PWG IPP Phone Conference - 980107

Attending: Carl-Uno Manros
Steve Zilles
Scott Isaacson
Roger deBry
Bob Herriot
Randy Turner
Ron Bergman
Harry Lewis
Tom Hastings
Peter Zehler
Xavier Riley
Ira Mcdonald

Main agenda points were to discuss the two remaining IPP issues and to talk
about plans for submission to the IESG and the upcoming meeting in Maui.

The first issue discussed was whether IPP clients SHOULD or SHALL implement
TLS. The decision was to go for SHOULD at this stage, considering the
non-availability of TLS software at this stage. This can be upgraded to a
SHALL when we move to Draft Standard, at which time everybody should have a
better view of foot print, performance degradation, and costs for
implementing TLS more widely.

The second issue was to discuss how a user (or IPP client) finds out about
the availability of TLS on a particular printer. Several proposals had been
discussed on the DL, with no clear winner. It was clear that we need to do
something about this in our specification as the TLS negotiation does not
allow negotiation to not use TLS. Alternatives about letting this be a
matter for the Directory and/or the IPP server were discussed. The agreed
solution was to resolve the issue by:

1) Removing the printer-tls-uri attribute and instead extend the
printer-uri to become a multi-valued attribute and call it
printer-uris-supported. This value should be accessible over the Directory
as well as stored in the Printer object, so that it can be retrieved with a
Get Printer Attributes operation.
Printer-uri in its current single value form will still be used as an
operational attribute in some of the operations.

2) As we may not be able to reliably determine from the URI sheme if it
supports TLS security or not, it was decided to also define a multi-valued
"meta-attribute" that would match the entries in the previous attribute,
describing whether security was offered by the matching uri in the
"printer-uris-supported" attribute. This makes IPP independent of future
changes in the use of schemes and port numbers for security. As for the
previous attribute, it should appear both in directory entries as well as
in the Printer object. Vales for the attribute are in the form of keywords,
with the following three values initially: NONE, TLS, SSL3.

Having resolved the TLS problem with the solution just described, it was
decided that Randy's proposal for redirection within IPP does not
neccesarily have to be included in IPP Version 1.0, so this will be left
for further discussion beyond the current set of specifications. It should
be on the PWG IPP agenda for Maui.

Tom Hastings brought up a smaller issue related to media orientation in
combination with finishing. It was decided to add another value for
orientation to be called "reversed-landscape" and to make some further
clarifications in the text. Tom will write up the proposed amended text for
this.

Some further minor suggestions about atribute name changes and value
reallocation were discussed and accepted for the final draft of the Model
document. The editors should also check that all references are fully
up-to-date and accurate.

In the light of succesful resolution of these last issues, it was decided
that the editors will all have their final drafts ready and submitted to
the IETF secretariat by January 9th. Carl-Uno will notify the IESG that we
are ready for their review as soon as all documents are ready. We will have
new versions of the Model, Protocol and Rationale documents, the other two
documents for Requirements and LPD Mapping are already in their final state.

Finally, some discussion of the IPP agenda for Maui was held. The latest
status is that Don Wright would like to start off the Wednesday meeting
with some general PWG discussions which are not limited to IPP. This might
take up to two hours. The rest of the day will be used to start discussing
some of the future extensions to IPP. Some of the extension discussions
might be carried over to Thursday, with the rest of the day to discuss
interoperability and testing. The exact split on Thursday will depend on
how many people actually show up for the interoperability and testing
subject. Carl-Uno will issue a more detailed agenda for Maui.

---

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