SDP Mail Archive: SDP> Charter eyeglasses

SDP> Charter eyeglasses

Harry Lewis (harryl@us.ibm.com)
Wed, 15 Apr 1998 18:24:26 -0400

We were having a "host-to-Device" discussion within IPP which, in Portl=
and, got
split off to become a separate, Server-to-Device, PWG group. Now, we ha=
ve to
debate which elements of printing belong to which protocol and which gr=
oup and
run the risk of channeling our discussion to one group while overlookin=
g the
other. The idea of splitting is supported by the notion that SDP like f=
unctions
are not in the IPP charter and that the concept of a "unified" protocol=
is
nonsense.

Re-reading, and presenting excerpts from the charter with capitalizatio=
n for
emphasis, I see that the charter, itself, may contribute some of the co=
nfusion
and frustration expressed in Portland...

Group-A... Universal protocol, grow IPP to encompass SDP requirements.

"There is currently NO UNIVERSAL STANDARD FOR PRINTING. Several protoco=
ls are
in use, but each has limited applicability and none can be considered t=
he
prevalent one. This means that printer vendors have to implement and su=
pport a
number of different protocols and protocol variants. There is a need to=
define
a protocol which can cover the most common situations for printing on t=
he
Internet."

"The further goal is to define a new application level Internet Printin=
g
Protocol for the following core functions:

- for a user to find out about a PRINTER's CAPABILITIES
- for a user to submit print jobs TO A PRINTER
- for a user to find out the STATUS OF A PRINTER or a print job
- for a user to cancel a previously submitted job"

"The Internet Print Protocol is a client-server type protocol which
should allow the server side to be either a separate print server or
a PRINTER WITH EMBEDDED NETWORKING capabilities. The focus of this
effort is optimized for PRINTERS, but might be applied to other
OUTPUT DEVICES. These are outside the scope of this working group."

Group-B... IPP to server only, Totally separate SDP discussion.

"There is currently no universal standard for printing. Several protoco=
ls are
in use, but each has limited applicability and none can be considered t=
he
prevalent one. This means that printer vendors have to implement and su=
pport a
number of different protocols and protocol variants. There is a need to=
define
a protocol which can cover the most common situations for printing on t=
he
INTERNET."

"The further goal is to define a new APPLICATION LEVEL INTERNET PRINTIN=
G
Protocol for the following core functions:

- for a user to find out about a printer's capabilities
- for a user to submit print jobs to a printer
- for a user to find out the status of a printer or a print job
- for a user to cancel a previously submitted job"

"The Internet Print Protocol is a CLIENT-SERVER type protocol which
should allow the server side to be either a separate print server or
a printer with embedded networking capabilities. The focus of this
effort is optimized for printers, but might be applied to other output
devices. These are outside the scope of this working group."

Granted... ALL THE WORDS are there - I'm not trying to imply that
these are the ONLY words that people read and interpret. But, at least
I see how my interpretation of the charter must differ greatly with
some others and how the resulting mismatch in expectations is fueling
many of our current disagreements.

Harry Lewis - IBM Printing Systems
=