IPP> SLP - Comment on the SLP template (for Wed 1/12/00 telecon)

IPP> SLP - Comment on the SLP template (for Wed 1/12/00 telecon)

IPP> SLP - Comment on the SLP template (for Wed 1/12/00 telecon)

Hastings, Tom N hastings at cp10.es.xerox.com
Mon Jan 10 17:41:23 EST 2000

The SLP template looks good.

1. I have one typo:

        printer-uri-supported = STRING L
            # REQUIRED for all registrations by conforming SLP SAs
            # IPP 'printer-uri-supported'
            # The ORDERED list of URI supported by this printer,
            # correlated with 'uri-authentication-supported' values
            # and correlated with 'uri-security-supported' values.
            # Each list member is delimited by '>', for example:
            #   'lpr://foo.com> ipp://bar.com'>

The last line should have the ' last:

            #   'lpr://foo.com> ipp://bar.com>'

2. and one substantive comment:

I understand why we made the 'printer-location' an OPTIONAL attribute,
instead of a REQUIRED one:  because some forwarding server that queries an
IPP printer (that doesn't have the "printer-location" Printer Description
attribute filled in with the location of the Printer) will be unable to put
in a real location into the SLP directory.  So we need the 'unknown' value.
In SLP the only way to get the unknown value is to make the SLP attribute be

However, an SLP directory entry that doesn't say where the printer is
physically located isn't very useful in a directory.  After the user finds
the printer with SLP, if he/she can't then find where the output is coming
out, it wasn't worth finding the printer.  (We have such a directory at
Xerox with 1000s of printers on the entire internal network without the
physical location of the printers.  It is pretty useless for finding a
printer to use).  

Suggested solution:  Add a statement that it is strongly recommended that
this attribute be supported and filled in with a real value.

Here is the current text:

        printer-location = STRING O
            # IPP 'printer-location'
            # The physical location of this printer,
            # in the language in 'natural-language-configured'.
            # A free form description of this printer's physical
            # location, for example:
            #   '2nd floor, near the fire escape'
            # If this printer information is not known to the SLP SA,
            # then this attribute SHALL be set to 'unknown'.

Suggested additional sentence to be added to the end of the
'printer-location' attribute description:

            # However, it is STRONGLY RECOMMENDED that this attribute 
            # be supported and that it be filled in with a real value 
            # that will help people to determine the physical location 
            # of the printer in order to be able to pick up document output
            # after locating the printer on the network with SLP.

Tom Hastings

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