Independent Submission                                        P. Fleming
Request for Comments: 7612                                   Independent
Obsoletes: 3712                                              I. McDonald
Category: Informational                                       High North
ISSN: 2070-1721                                                June 2015

             Lightweight Directory Access Protocol (LDAP):
                      Schema for Printer Services

Abstract

   This document defines a schema, object classes, and attributes, for
   Printers and print services, for use with directories that support
   the Lightweight Directory Access Protocol (RFC 4510).  This document
   is based on the Printer attributes listed in Appendix E of "Internet
   Printing Protocol/1.1: Model and Semantics" (RFC 2911).  Additional
   Printer attributes are based on definitions in "Printer MIB v2" (RFC
   3805), "PWG Command Set Format for IEEE 1284 Device ID v1.0" (PWG
   5107.2), "IPP Job and Printer Extensions - Set 3 (JPS3)" (PWG
   5100.13), and "IPP Everywhere" (PWG 5100.14).

   This memo is an Independent Submission to the RFC Editor by the
   Internet Printing Protocol (IPP) Working Group of the IEEE-ISTO
   Printer Working Group (PWG), as part of their PWG "IPP Everywhere"
   (PWG 5100.14) project for secure mobile printing with vendor-neutral
   Client software.

   This document obsoletes RFC 3712.

Status of This Memo

   This document is not an Internet Standards Track specification; it is
   published for informational purposes.

   This is a contribution to the RFC Series, independently of any other
   RFC stream.  The RFC Editor has chosen to publish this document at
   its discretion and makes no statement about its value for
   implementation or deployment.  Documents approved for publication by
   the RFC Editor are not a candidate for any level of Internet
   Standard; see Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc7612.

Copyright Notice

   Copyright (c) 2015 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.

Table of Contents

   1. Introduction ....................................................4
      1.1. Relationship to SLP Printer Service ........................4
      1.2. Source of LDAP Printer Attributes ..........................4
      1.3. Source of LDAP Printer Schema OIDs .........................5
           1.3.1. IBM Assignments for RFC 3712 ........................5
           1.3.2. IEEE-ISTO PWG Assignments ...........................5
      1.4. Rationale for Design Choices ...............................5
           1.4.1. Rationale for Using DirectoryString Syntax ..........5
           1.4.2. Rationale for Using caseIgnoreMatch .................6
           1.4.3. Rationale for Using caseIgnoreSubstringsMatch .......7
   2. Conventions Used in This Document ...............................8
      2.1. Requirements Language ......................................8
      2.2. LDAP Schema Descriptions ...................................8
      2.3. Abbreviations ..............................................8
   3. Definition of Object Classes ....................................9
      3.1. slpServicePrinter .........................................10
      3.2. printerAbstract ...........................................10
      3.3. printerService ............................................11
      3.4. printerServiceAuxClass ....................................12
      3.5. printerIPP ................................................12
      3.6. printerLPR ................................................12
   4. Definition of Attribute Types ..................................13
      4.1. printer-uri ...............................................15
      4.2. printer-xri-supported .....................................16
      4.3. printer-name ..............................................18
      4.4. printer-natural-language-configured .......................19
      4.5. printer-location ..........................................19
      4.6. printer-info ..............................................20
      4.7. printer-more-info .........................................21
      4.8. printer-make-and-model ....................................21
      4.9. printer-ipp-versions-supported ............................22
      4.10. printer-multiple-document-jobs-supported .................23
      4.11. printer-charset-configured ...............................23
      4.12. printer-charset-supported ................................24
      4.13. printer-generated-natural-language-supported .............24
      4.14. printer-document-format-supported ........................25
      4.15. printer-color-supported ..................................25
      4.16. printer-compression-supported ............................26
      4.17. printer-pages-per-minute .................................26
      4.18. printer-pages-per-minute-color ...........................27
      4.19. printer-finishings-supported .............................27
      4.20. printer-number-up-supported ..............................28
      4.21. printer-sides-supported ..................................28
      4.22. printer-media-supported ..................................29
      4.23. printer-media-local-supported ............................30
      4.24. printer-resolution-supported .............................30
      4.25. printer-print-quality-supported ..........................31
      4.26. printer-job-priority-supported ...........................32
      4.27. printer-copies-supported .................................32
      4.28. printer-job-k-octets-supported ...........................33
      4.29. printer-current-operator .................................33
      4.30. printer-service-person ...................................34
      4.31. printer-delivery-orientation-supported ...................34
      4.32. printer-stacking-order-supported .........................35
      4.33. printer-output-features-supported ........................36
      4.34. printer-aliases ..........................................37
      4.35. printer-device-id ........................................37
      4.36. printer-device-service-count .............................38
      4.37. printer-uuid .............................................38
      4.38. printer-charge-info ......................................39
      4.39. printer-charge-info-uri ..................................39
      4.40. printer-geo-location .....................................40
      4.41. printer-ipp-features-supported ...........................41
   5. Definition of Syntaxes .........................................42
   6. Definition of Matching Rules ...................................42
   7. IANA Considerations ............................................42
      7.1. Registration of Attribute Types ...........................43
      7.2. Object Classes and Attribute Types from RFC 3712 ..........44
   8. Internationalization Considerations ............................45
   9. Security Considerations ........................................45
   10. References ....................................................46
      10.1. Normative References .....................................46
      10.2. Informative References ...................................50
   Appendix A. Changes since RFC 3712 ................................52
   Acknowledgments ...................................................54
   Authors' Addresses ................................................54

1.  Introduction

   This document defines several object classes to provide Lightweight
   Directory Access Protocol (LDAP) [RFC4510] applications with flexible
   options in defining Printer information using an LDAP schema.
   Classes are provided for defining directory entries with common
   Printer information as well as for extending existing directory
   entries with Service Location Protocol Version 2 (SLPv2) [RFC2608],
   Internet Printing Protocol/1.1 (IPP/1.1) [RFC2911], and lineprinter
   (LPR) [RFC1179] protocol-specific information.

   This memo is an Independent Submission to the RFC Editor by the
   Internet Printing Protocol Working Group of the IEEE-ISTO Printer
   Working Group, as part of their Printer Working Group (PWG) "IPP
   Everywhere" (PWG 5100.14) project for secure mobile printing with
   vendor-neutral Client software.

1.1.  Relationship to SLP Printer Service

   The schema defined in this document is technically aligned with the
   stable IANA-registered 'service:printer:' v2.0 template [SLPPRT20],
   for compatibility with already-deployed SLPv2 [RFC2608] service
   advertising and discovery infrastructure.  The attribute syntaxes are
   technically aligned with the 'service:printer:' v2.0 template;
   therefore, simpler types are sometimes used (for example,
   'DirectoryString' [RFC4517] rather than 'labeledURI' [RFC2079] for
   the 'printer-uri' attribute).

1.2.  Source of LDAP Printer Attributes

   The schema defined in this document is based on:

   o  all of the Printer attributes listed in Appendix E ("Generic
      Directory Schema") of "Internet Printing Protocol/1.1: Model and
      Semantics" [RFC2911] that are defined in Section 4.4 ("Printer
      Description Attributes") of [RFC2911]

   o  selected Printer attributes defined in "Printer MIB v2" [RFC3805],
      "PWG Command Set for IEEE 1284 Device ID v1.0" [PWG5107.2], "IPP
      Job and Printer Extensions - Set 3 (JPS3)" [PWG5100.13], and "IPP
      Everywhere" [PWG5100.14]

   See the table of Printer attributes and source documents in Section 4
   ("Definition of Attribute Types") of this document.

1.3.  Source of LDAP Printer Schema OIDs

1.3.1.  IBM Assignments for RFC 3712

   In March 2000, IBM permanently assigned ASN.1 OIDs to all of the
   object classes and attribute types that were defined in the original
   LDAP Printer Schema [RFC3712] (see Section 7.2).

1.3.2.  IEEE-ISTO PWG Assignments

   In October 2011, IBM permanently delegated the base ASN.1 OID
   "1.3.18.0.2.24.46" to the IEEE-ISTO PWG for use in any PWG project.
   In October 2011, the IEEE-ISTO PWG permanently assigned subordinate
   ASN.1 OIDs for all of the new attribute types defined in this updated
   LDAP Printer Schema (see Section 7.1).

1.4.  Rationale for Design Choices

1.4.1.  Rationale for Using DirectoryString Syntax

   The attribute syntax 'DirectoryString' (UTF-8 [STD63]) defined in
   [RFC4517] is specified for several groups of string attributes that
   are defined in this document:

   1) URI

      - printer-uri, printer-xri-supported, printer-more-info,
        printer-charge-info-uri, printer-uuid

        The UTF-8 encoding is compatible with deployment of (UTF-8
        based) Internationalized Resource Identifiers (IRIs) [RFC3987].

   2) Description

      - printer-name, printer-location, printer-info,
        printer-make-and-model

        The UTF-8 encoding supports descriptions in any language,
        conformant with the IETF Policy on Character Sets and Languages
        [BCP18].

        Note: The printer-natural-language-configured attribute contains
        a language tag [BCP47] for these description attributes (for
        example, to support text-to-speech conversions).

   3) Keyword

      - printer-compression-supported, printer-finishings-supported,
        printer-media-supported, printer-media-local-supported,
        printer-print-quality-supported

        The UTF-8 encoding is compatible with the current IPP/1.1
        [RFC2911] definition of the equivalent attributes, most of which
        have the IPP/1.1 union syntax 'keyword' or 'name'.  The keyword
        attributes defined in this document are extensible by site-
        specific or vendor-specific 'names' that behave like new
        'keywords'.

        Note: In IPP/1.1, each value is strongly typed over-the-wire as
        either 'keyword' or 'name'.  This union selector is not
        preserved in the definitions of these equivalent LDAP
        attributes.

1.4.2.  Rationale for Using caseIgnoreMatch

   The EQUALITY matching rule 'caseIgnoreMatch' defined in [RFC4517] is
   specified for several groups of string attributes that are defined in
   this document:

   1) URI

      These URI attributes specify EQUALITY matching with
      'caseIgnoreMatch' (rather than with 'caseExactMatch') in order to
      conform to the spirit of [STD66], which requires case-insensitive
      matching on the host part of a URI versus case-sensitive matching
      on the remainder of a URI.

      These URI attributes follow existing practice of supporting
      case-insensitive equality matching for host names in the
      associatedDomain attribute defined in [RFC4524].

      Either equality matching rule choice would be a compromise:

      a) case-sensitive whole URI matching can lead to false negative
         matches and has been shown to be fragile (given deployed client
         applications that 'pretty up' host names displayed and
         transferred in URI);

      b) case-insensitive whole URI matching can lead to false positive
         matches, although it is a dangerous practice to publish URI
         that differ only by case (for example, in the path elements).

   2) Description

      Case-insensitive equality matching is more user-friendly for
      description attributes.

   3) Keyword

      Case-insensitive equality matching is more user-friendly for
      keyword attributes.

   4) IEEE 1284 Device ID

      Case-insensitive equality matching is mandatory for IEEE 1284
      Device ID attributes.

1.4.3.  Rationale for Using caseIgnoreSubstringsMatch

   The SUBSTR matching rule 'caseIgnoreSubstringsMatch' defined in
   [RFC4517] is specified for several groups of string attributes that
   are defined in this document:

   1) URI

      These URI attributes follow existing practice of supporting
      case-insensitive equality matching for host names in the
      associatedDomain attribute defined in [RFC4524].

   2) Description

      Support for case-insensitive substring matching is more
      user-friendly for description attributes.

   3) Keyword

      Support for case-insensitive substring matching is more
      user-friendly for keyword attributes.

   4) IEEE 1284 Device ID

      Support for case-insensitive substring matching is mandatory for
      IEEE 1284 Device ID attributes.

2.  Conventions Used in This Document

2.1.  Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

2.2.  LDAP Schema Descriptions

   Schema definitions are provided using LDAP [RFC4510] description
   formats.  Definitions provided here are formatted (line wrapped) for
   readability.

2.3.  Abbreviations

   This document makes use of the following abbreviations (given with
   their expanded forms and references for further reading):

   IANA   - Internet Assigned Numbers Authority
            <http://www.iana.org>

   IEEE   - Institute of Electrical and Electronics Engineers
            <http://www.ieee.org>

   IPP    - Internet Printing Protocol [RFC2911] [PWG5100.12]
            <http://www.pwg.org/ipp/>

   ISTO   - IEEE Industry Standards and Technology Organization
            <http://www.ieee-isto.org/>

   PWG    - IEEE-ISTO Printer Working Group
            <http://www.pwg.org>

   RFC    - Request for Comments
            <http://www.rfc-editor.org>

   TLS    - Transport Layer Security [RFC5246]

   URI    - Uniform Resource Identifier [STD66]

   URL    - Uniform Resource Locator [STD66]

   UTF-8  - Unicode Transformation Format - 8-bit [STD63]

3.  Definition of Object Classes

   We define the following LDAP object classes for use with both generic
   Printer-related information and services specific to SLPv2 [RFC2608],
   IPP/1.1 [RFC2911], and LPR [RFC1179].

      slpServicePrinter - auxiliary class for SLP-registered Printers
      printerAbstract - abstract class for all Printer classes
      printerService - structural class for Printers
      printerServiceAuxClass - auxiliary class for Printers
      printerIPP - auxiliary class for IPP Printers
      printerLPR - auxiliary class for LPR Printers

   The following are some examples of how applications could choose to
   use these classes when creating directory entries:

   1) Use printerService for directory entries containing common Printer
      information.

   2) Use both printerService and slpServicePrinter for directory
      entries containing common Printer information for SLP-registered
      Printers.

   3) Use printerService, printerLPR, and printerIPP for directory
      entries containing common Printer information for Printers that
      support both LPR and IPP.

   4) Use printerServiceAuxClass and object classes not defined by this
      document for directory entries containing common Printer
      information.  In this example, printerServiceAuxClass is used for
      extending other structural classes defining Printer information
      with common Printer information defined in this document.

   Refer to Section 4 for the definition of attribute types referenced
   by these object classes.  We use attribute names instead of OIDs in
   object class definitions for clarity.  Some attribute names described
   in [RFC2911] have been prefixed with 'printer-' as recommended in
   [RFC2926] and [SLPPRT20].

3.1.  slpServicePrinter

   ( 1.3.18.0.2.6.254
   NAME  'slpServicePrinter'
   DESC  'Service Location Protocol (SLP) information.'
   AUXILIARY
   SUP   slpService
   )

   This auxiliary class defines information specific to the Service
   Location Protocol (SLPv2) [RFC2608].  It MAY be used to create new,
   or extend existing, directory entries with SLP 'service:printer'
   abstract service type information as defined in [SLPPRT20].  This
   object class is derived from 'slpService', the parent class for all
   SLP services, defined in [RFC2926].

3.2.  printerAbstract

   ( 1.3.18.0.2.6.258
   NAME  'printerAbstract'
   DESC  'Printer-related information.'
   ABSTRACT
   SUP   top
   MAY   ( printer-name $
           printer-natural-language-configured $
           printer-location $
           printer-info $
           printer-more-info $
           printer-make-and-model $
           printer-multiple-document-jobs-supported $
           printer-charset-configured $
           printer-charset-supported $
           printer-generated-natural-language-supported $
           printer-document-format-supported $
           printer-color-supported $
           printer-compression-supported $
           printer-pages-per-minute $
           printer-pages-per-minute-color $
           printer-finishings-supported $
           printer-number-up-supported $
           printer-sides-supported $
           printer-media-supported $
           printer-media-local-supported $
           printer-resolution-supported $
           printer-print-quality-supported $
           printer-job-priority-supported $
           printer-copies-supported $
           printer-job-k-octets-supported $
           printer-current-operator $
           printer-service-person $
           printer-delivery-orientation-supported $
           printer-stacking-order-supported $
           printer-output-features-supported $
           printer-device-id $
           printer-device-service-count $
           printer-uuid $
           printer-charge-info $
           printer-charge-info-uri $
           printer-geo-location )
   )

   This abstract class defines Printer information.  It is a base class
   for deriving other Printer-related classes, such as, but not limited
   to, classes defined in this document.  It defines a common set of
   Printer attributes that are not specific to any one type of service,
   protocol, or operating system.

3.3.  printerService

   ( 1.3.18.0.2.6.255
   NAME  'printerService'
   DESC  'Printer information.'
   STRUCTURAL
   SUP   printerAbstract
   MAY   ( printer-uri $
           printer-xri-supported )
   )

   This structural class defines Printer information.  It is derived
   from class printerAbstract and thus inherits common Printer
   attributes.  This class can be used with or without auxiliary classes
   to define Printer information.  Auxiliary classes can be used to
   extend the common Printer information with information specific to
   the protocol, service, or operating system.

   Note: When extending other structural classes with auxiliary classes,
   printerService SHOULD NOT be used.

3.4.  printerServiceAuxClass

   ( 1.3.18.0.2.6.257
   NAME  'printerServiceAuxClass'
   DESC  'Printer information.'
   AUXILIARY
   SUP   printerAbstract
   MAY   ( printer-uri $
           printer-xri-supported )
   )

   This auxiliary class defines Printer information.  It is derived from
   class printerAbstract and thus inherits common Printer attributes.

3.5.  printerIPP

   ( 1.3.18.0.2.6.256
   NAME  'printerIPP'
   DESC  'Internet Printing Protocol (IPP) information.'
   AUXILIARY
   SUP   top
   MAY   ( printer-ipp-versions-supported $
           printer-ipp-features-supported $
           printer-multiple-document-jobs-supported )
   )

   This auxiliary class defines Internet Printing Protocol (IPP/1.1)
   [RFC2911] information.  It is used to extend structural classes with
   IPP-specific Printer information.

   Note: See "Internet Printing Protocol/1.1: IPP URL Scheme" [RFC3510]
   and "Internet Printing Protocol (IPP) over HTTPS Transport Binding
   and the 'ipps' URI Scheme" [RFC7472] for conforming URI for IPP
   Printers.

3.6.  printerLPR

   ( 1.3.18.0.2.6.253
   NAME  'printerLPR'
   DESC  'LPR information.'
   AUXILIARY
   SUP   top
   MUST  ( printer-name )
   MAY   ( printer-aliases )
   )

   This auxiliary class defines LPR [RFC1179] information.  It is used
   to identify directory entries that support LPR.

4.  Definition of Attribute Types

   The following attribute types are referenced by the object classes
   defined in Section 3.

   The following attribute types reference syntax OIDs defined in
   Section 3 of [RFC4517] (see Section 5 ("Definition of Syntaxes")
   below).

   The following attribute types reference matching rule names (instead
   of OIDs) for clarity (see Section 6 below).  For optional attributes,
   if the Printer information is not known, the attribute value
   SHOULD NOT be set.  In the following definitions, referenced matching
   rules are defined in Section 4 of [RFC4517] and discussed in
   Section 6 ("Definition of Matching Rules") later in this document.

   Note: For compatibility with existing implementations of [RFC3712]
   and underlying string length limits in [RFC2707], [RFC2911],
   [RFC3805], [PWG5107.2], [PWG5100.13], and [PWG5100.14],
   implementations of the attributes defined in this document SHOULD NOT
   exceed those underlying string length limits (to avoid truncation and
   false matches).

   Note: For interoperability and consistent text display, values of
   attributes defined in this document (a) SHOULD be normalized as
   recommended in "Unicode Format for Network Interchange" [RFC5198];
   (b) SHOULD NOT contain DEL or any C0 or C1 control characters except
   for HT, CR, and LF; (c) SHOULD only contain CR and LF characters
   together (not as singletons); and (d) SHOULD NOT contain HT, CR, or
   LF characters in names, e.g., printer-name and printer-aliases.

   Note: Some of the following attributes are described as 'List of xxx'
   (using a comma as the member delimiter).  Some other attributes are
   described as 'One of xxx' (single-valued).  In all cases, any
   attribute can have multiple values represented as multiple instances,
   except where explicitly restricted in syntax to be single-valued.

   Note: Values of the string attributes printer-xri-supported and
   printer-resolution-supported use different field delimiters ('<' and
   '>', respectively).  These two field delimiters are different for
   compatibility with the corresponding attributes in the IANA-
   registered SLP 'service:printer:' v2.0 template [SLPPRT20], which was
   defined before the original LDAP Printer Schema [RFC3712] was
   written.

   The following table is a summary of the attribute names defined by
   this document and their corresponding source document names as
   defined in [RFC2911], [RFC3805], [PWG5107.2], or [PWG5100.13].  Some
   source attribute names have been prefixed with 'printer-' as
   recommended in [RFC2926], to address the flat namespace for LDAP
   identifiers.

   LDAP and SLP Printer Schema     Source Document and Attribute Name
   ------------------------------  -------------------------------------
   ***                             IPP/1.1 and Semantics Model [RFC2911]
   printer-uri
   printer-xri-supported
                                   [printer-uri-supported]
                                   [uri-authentication-supported]
                                   [uri-security-supported]
   printer-name                    printer-name
   printer-natural-language-configured
                                   natural-language-configured
   printer-location                printer-location
   printer-info                    printer-info
   printer-more-info               printer-more-info
   printer-make-and-model          printer-make-and-model
   printer-ipp-versions-supported  ipp-versions-supported
   printer-multiple-document-jobs-supported
                                   multiple-document-jobs-supported
   printer-charset-configured      charset-configured
   printer-charset-supported       charset-supported
   printer-generated-natural-language-supported
                                   generated-natural-language-supported
   printer-document-format-supported
                                   document-format-supported
   printer-color-supported         color-supported
   printer-compression-supported   compression-supported
   printer-pages-per-minute        pages-per-minute
   printer-pages-per-minute-color  pages-per-minute-color
   printer-finishings-supported    finishings-supported
   printer-number-up-supported     number-up-supported
   printer-sides-supported         sides-supported
   printer-media-supported         media-supported
   printer-media-local-supported   [site names from IPP media-supported]
   printer-resolution-supported    printer-resolution-supported
   printer-print-quality-supported print-quality-supported
   printer-job-priority-supported  job-priority-supported
   printer-copies-supported        copies-supported
   printer-job-k-octets-supported  job-k-octets-supported
   ***                             Printer MIB v2 [RFC3805]
   printer-current-operator        prtGeneralCurrentOperator
   printer-service-person          prtGeneralServicePerson
   printer-delivery-orientation-supported
                                   prtOutputPageDeliveryOrientation
   printer-stacking-order-supported
                                   prtOutputStackingOrder
   printer-output-features-supported
                                   [prtOutputBursting]
                                   [prtOutputDecollating]
                                   [prtOutputPageCollated]
                                   [prtOutputOffsetStacking]
   printer-aliases                 prtGeneralPrinterName

   ***                             Cmd Set 1284 Device ID [PWG5107.2]
   printer-device-id               printer-device-id

   ***                             IPP Job/Printer Ext Set3 [PWG5100.13]
   printer-device-service-count    device-service-count
   printer-uuid                    printer-uuid
   printer-charge-info             printer-charge-info
   printer-charge-info-uri         printer-charge-info-uri
   printer-geo-location            printer-geo-location
   printer-ipp-features-supported  ipp-features-supported

4.1.  printer-uri

   ( 1.3.18.0.2.4.1140
   NAME 'printer-uri'
   DESC 'A URI supported by this Printer.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   SINGLE-VALUE
   )

   If the printer-xri-supported LDAP attribute is implemented, then this
   printer-uri value MUST be listed in printer-xri-supported.

   See [STD66] for details of URI syntax.

   Note: For compatibility with IPP/1.1 [RFC2911], values of this
   attribute SHOULD NOT exceed 1023 octets in length.

   Note: LDAP application clients SHOULD NOT attempt to use malformed
   URI values read from this attribute.  LDAP administrative clients
   SHOULD NOT write malformed URI values into this attribute.

   Note: See "Internet Printing Protocol/1.1: IPP URL Scheme" [RFC3510]
   and "Internet Printing Protocol (IPP) over HTTPS Transport Binding
   and the 'ipps' URI Scheme" [RFC7472] for conforming URI for IPP
   Printers.

   Note: For SLP-registered Printers, the LDAP printer-uri attribute
   SHOULD be set to the value of the SLP-registered URL of the Printer,
   for interworking with SLPv2 [RFC2608] service discovery.

   Note: See Sections 1.4.1, 1.4.2, and 1.4.3 for rationale for design
   choices.

4.2.  printer-xri-supported

   ( 1.3.18.0.2.4.1107
   NAME 'printer-xri-supported'
   DESC 'An XRI (extended resource identifier) supported by
         this Printer.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   )

   Each value of this attribute MUST consist of a URI (uniform resource
   identifier) followed by (optional) authentication and security
   fields.

   Each XRI field MUST be delimited by '<', with optional trailing
   whitespace.  For example:

      'uri=ipp://example.com/ipp< auth=digest< sec=tls<'
      'uri=ipps://example.com/ipp< auth=digest< sec=tls<'
      'uri=lpr://example.com/lpr< auth=none< sec=none<'
      'uri=mailto:printer@example.com< auth=none< sec=none<'

   Note: See the note in Section 4 about the different field delimiters
   used in the printer-xri-supported and printer-resolution-supported
   attributes ('<' and '>', respectively), chosen for compatibility with
   the IANA-registered SLP 'service:printer:' v2.0 template [SLPPRT20].

   Note: Multiple values for this attribute are represented as multiple
   instances of this attribute.

   See [STD66] for details of URI syntax.

   Note: For compatibility with IPP/1.1 [RFC2911], values of this
   attribute SHOULD NOT exceed 1023 octets in length.

   Note: LDAP application clients SHOULD NOT attempt to use malformed
   URI values read from this attribute.  LDAP administrative clients
   SHOULD NOT write malformed URI values into this attribute.

   Note: This attribute is based on the IPP/1.1 [RFC2911] attributes
   'printer-uri-supported', 'uri-authentication-supported', and
   'uri-security-supported' (called the 'Three Musketeers' because they
   are parallel, ordered attributes).  This attribute unfolds those
   IPP/1.1 attributes and thus avoids the ordering (and same number of
   values) constraints of the IPP/1.1 separate attributes.

   Defined keywords for fields include:

      'uri' (IPP 'printer-uri-supported')
      'auth' (IPP 'uri-authentication-supported')
      'sec' (IPP 'uri-security-supported')

   A missing 'auth' field SHOULD be interpreted to mean 'none'.  Per
   IPP/1.1 [RFC2911], "IPP Job and Printer Extensions - Set 3 (JPS3)"
   [PWG5100.13], and the IANA IPP registry [IANAIPP], defined values of
   the 'auth' field include:

      'none' (no authentication for this URI)
      'requesting-user-name' (from operation request)
      'basic' (HTTP/1.1 Basic [RFC2617] and [RFC7235])
      'digest' (HTTP/1.1 Digest [RFC2617] and [RFC7235])
      'certificate' (X.509 Certificate [RFC5280] and [RFC6818])
      'negotiate' (HTTP/1.1 Negotiate [RFC4559])

   The 'certificate' value refers to the IPP Client certificate
   extracted from the TLS session.

   A missing 'sec' field SHOULD be interpreted to mean 'none'.  Per
   IPP/1.1 [RFC2911] and the IANA IPP registry [IANAIPP], defined values
   of the 'sec' field include:

      'none' (no security for this URI)
      'ssl3' (Netscape's Secure Socket Layer protocol (SSL3))
      'tls' (IETF TLS, [RFC5246])

   Note: The syntax and delimiter for this attribute are aligned with
   the equivalent attribute in the 'service:printer:' v2.0 template
   [SLPPRT20].  Whitespace is permitted after (but not before) the
   delimiter '<'.

   Note: See "Internet Printing Protocol/1.1: IPP URL Scheme" [RFC3510]
   and "Internet Printing Protocol (IPP) over HTTPS Transport Binding
   and the 'ipps' URI Scheme" [RFC7472] for conforming URI for IPP
   Printers.

   Note: See Sections 1.4.1, 1.4.2, and 1.4.3 for rationale for design
   choices.

4.3.  printer-name

   ( 1.3.18.0.2.4.1135
   NAME 'printer-name'
   DESC 'The site-specific administrative name of this Printer.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   SINGLE-VALUE
   )

   Values of this attribute SHOULD be specified in the language
   specified in printer-natural-language-configured (for example, to
   support text-to-speech conversions), although the Printer's name MAY
   be specified in any language.

   Note: For compatibility with IPP/1.1 [RFC2911], values of this
   attribute SHOULD NOT exceed 255 octets in length.

   Note: This name can be the last part of the Printer's URI, or it can
   be completely unrelated.  This name can contain characters that are
   not allowed in a conventional URI (see [STD66]).

   Note: For interoperability, values of this attribute (a) SHOULD be
   normalized as recommended in "Unicode Format for Network Interchange"
   [RFC5198]; and (b) SHOULD NOT contain DEL or any C0 or C1 control
   characters.

4.4.  printer-natural-language-configured

   ( 1.3.18.0.2.4.1119
   NAME 'printer-natural-language-configured'
   DESC 'The configured natural language for LDAP attributes of
         syntax DirectoryString (UTF-8) in this directory entry.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   SINGLE-VALUE
   )

   Also, a possible natural language for IPP protocol string attributes
   set by operator, system administrator, or manufacturer.  Also, the
   (declared) natural language of the printer-name, printer-location,
   printer-info, and printer-make-and-model attributes of this Printer.

   Values of language tags MUST conform to "Tags for Identifying
   Languages" [BCP47].  For example:

      'en-us' (English as spoken in the US)
      'fr-fr' (French as spoken in France)

   Note: For compatibility with IPP/1.1 [RFC2911], values of this
   attribute SHOULD NOT exceed 63 octets in length.

   Note: For compatibility with IPP/1.1 [RFC2911], language tags in this
   attribute SHOULD be lowercase normalized.

4.5.  printer-location

   ( 1.3.18.0.2.4.1136
   NAME 'printer-location'
   DESC 'The physical location of this Printer.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   SINGLE-VALUE
   )

   For example:

      'Room 123A'
      'Second floor of building XYZ'

   Note: For compatibility with IPP/1.1 [RFC2911], values of this
   attribute SHOULD NOT exceed 127 octets in length.

   Note: For interoperability and consistent text display, values of
   this attribute (a) SHOULD be normalized as recommended in "Unicode
   Format for Network Interchange" [RFC5198]; (b) SHOULD NOT contain DEL
   or any C0 or C1 control characters except for HT, CR, and LF; and
   (c) SHOULD only contain CR and LF characters together (not as
   singletons).

4.6.  printer-info

   ( 1.3.18.0.2.4.1139
   NAME 'printer-info'
   DESC 'Descriptive information about this Printer.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   SINGLE-VALUE
   )

   For example:

      'This Printer can be used for printing color transparencies for
       HR presentations'

      'Out of courtesy for others, please print only small (1-5 page)
       jobs at this Printer'

      'This Printer is going away on July 1, 1997; please find a new
       Printer'

   Note: For compatibility with IPP/1.1 [RFC2911], values of this
   attribute SHOULD NOT exceed 127 octets in length.

   Note: For interoperability and consistent text display, values of
   this attribute (a) SHOULD be normalized as recommended in "Unicode
   Format for Network Interchange" [RFC5198]; (b) SHOULD NOT contain DEL
   or any C0 or C1 control characters except for HT, CR, and LF; and
   (c) SHOULD only contain CR and LF characters together (not as
   singletons).

4.7.  printer-more-info

   ( 1.3.18.0.2.4.1134
   NAME 'printer-more-info'
   DESC 'A URI for more information about this specific Printer.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   SINGLE-VALUE
   )

   For example, this could be an HTTP URI referencing an HTML page
   accessible to a Web Browser.  The information obtained from this URI
   is intended for end user consumption.

   See [STD66] for details of URI syntax.

   Note: For compatibility with IPP/1.1 [RFC2911], values of this
   attribute SHOULD NOT exceed 1023 octets in length.

   Note: LDAP application clients SHOULD NOT attempt to use malformed
   URI values read from this attribute.  LDAP administrative clients
   SHOULD NOT write malformed URI values into this attribute.

   Note: See Sections 1.4.1, 1.4.2, and 1.4.3 for rationale for design
   choices.

4.8.  printer-make-and-model

   ( 1.3.18.0.2.4.1138
   NAME 'printer-make-and-model'
   DESC 'Make and model of this Printer.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   SINGLE-VALUE
   )

   Note: For compatibility with IPP/1.1 [RFC2911], values of this
   attribute SHOULD NOT exceed 127 octets in length.

   Note: The Printer manufacturer MAY initially populate this attribute.

   Note: For interoperability and consistent text display, values of
   this attribute (a) SHOULD be normalized as recommended in "Unicode
   Format for Network Interchange" [RFC5198]; (b) SHOULD NOT contain DEL
   or any C0 or C1 control characters except for HT, CR, and LF; and
   (c) SHOULD only contain CR and LF characters together (not as
   singletons).

4.9.  printer-ipp-versions-supported

   ( 1.3.18.0.2.4.1133
   NAME 'printer-ipp-versions-supported'
   DESC 'Comma-delimited list of IPP versions supported by
         this Printer.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   )

   For example:

      '1.1,2.0'

   Note: Length overflow in values of this attribute MUST be handled by
   multiple instances of this attribute, i.e., individual
   comma-delimited list members MUST NOT be truncated.

   The IPP protocol version(s) MUST include major and minor versions,
   i.e., the exact version numbers for which this Printer implementation
   meets the IPP version-specific conformance requirements as registered
   in the IANA IPP registry [IANAIPP].

   IANA-registered versions of IPP currently are:

      '1.0' (IPP/1.0 [RFC2566], OBSOLETE)
      '1.1' (IPP/1.1 [RFC2911])
      '2.0' (IPP/2.0 [PWG5100.12])
      '2.1' (IPP/2.1 [PWG5100.12])
      '2.2' (IPP/2.2 [PWG5100.12])

4.10.  printer-multiple-document-jobs-supported

   ( 1.3.18.0.2.4.1132
   NAME 'printer-multiple-document-jobs-supported'
   DESC 'Indicates whether or not this Printer supports more than one
         document per job.'
   EQUALITY booleanMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.7
   SINGLE-VALUE
   )

4.11.  printer-charset-configured

   ( 1.3.18.0.2.4.1109
   NAME 'printer-charset-configured'
   DESC 'The configured charset for IPP protocol values of error
         and status messages generated by this Printer.'
   EQUALITY caseIgnoreMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   SINGLE-VALUE
   )

   Also, a possible charset for IPP protocol string attributes set by
   operator, system administrator, or manufacturer.  For example:

      'utf-8' (ISO 10646/Unicode in UTF-8 transform [STD63])
      'iso-8859-1' (ISO Latin1)

   Values of charset tags SHOULD be defined in the IANA registry of
   Character Sets [IANACHAR] (see also [BCP19]), and the '(preferred
   MIME name)' SHOULD be used as the charset tag in this attribute.

   Note: For compatibility with IPP/1.1 [RFC2911], values of this
   attribute SHOULD NOT exceed 63 octets in length.

   Note: For compatibility with IPP/1.1 [RFC2911], charset tags in this
   attribute SHOULD be lowercase normalized.

4.12.  printer-charset-supported

   ( 1.3.18.0.2.4.1131
   NAME 'printer-charset-supported'
   DESC 'One of the charsets supported for IPP protocol values of
         IPP string attributes that correspond to attributes of
         syntax DirectoryString (UTF-8) for this directory entry.'
   EQUALITY caseIgnoreMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   )

   For example:

      'utf-8' (ISO 10646/Unicode in UTF-8 transform [STD63])
      'iso-8859-1' (ISO Latin1)

   Note: Multiple values for this attribute are represented as multiple
   instances of this attribute.

   Values of charset tags SHOULD be defined in the IANA registry of
   Character Sets [IANACHAR] (see also [BCP19]), and the '(preferred
   MIME name)' SHOULD be used as the charset tag in this attribute.

   Note: For compatibility with IPP/1.1 [RFC2911], values of this
   attribute SHOULD NOT exceed 63 octets in length.

   Note: For compatibility with IPP/1.1 [RFC2911], charset tags in this
   attribute SHOULD be lowercase normalized.

4.13.  printer-generated-natural-language-supported

   ( 1.3.18.0.2.4.1137
   NAME 'printer-generated-natural-language-supported'
   DESC 'One of the natural languages supported for LDAP attributes of
         syntax DirectoryString (UTF-8) in this directory entry.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   )

   Values of language tags SHOULD conform to "Tags for Identifying
   Languages" [BCP47].  For example:

      'en-us' (English as spoken in the US)
      'fr-ca' (French as spoken in Canada)

   Note: Multiple values for this attribute are represented as multiple
   instances of this attribute.

   Note: For compatibility with IPP/1.1 [RFC2911], values of this
   attribute SHOULD NOT exceed 63 octets in length.

   Note: For compatibility with IPP/1.1 [RFC2911], language tags in this
   attribute SHOULD be lowercase normalized.

4.14.  printer-document-format-supported

   ( 1.3.18.0.2.4.1130
   NAME 'printer-document-format-supported'
   DESC 'One of the source document formats that can be interpreted
         and printed by this Printer.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   )

   Values of document formats SHOULD be MIME media types defined in the
   IANA registry of MIME Media Types [IANAMIME] (see also [BCP13]).

   For example:

      'application/postscript' (Adobe PostScript)
      'text/plain' (plain text)

   Note: Multiple values for this attribute are represented as multiple
   instances of this attribute.

   Note: For compatibility with IPP/1.1 [RFC2911], values of this
   attribute SHOULD NOT exceed 255 octets in length.

4.15.  printer-color-supported

   ( 1.3.18.0.2.4.1129
   NAME 'printer-color-supported'
   DESC 'Indicates whether or not this Printer is capable of any type of
         color printing at all, including highlight color.'
   EQUALITY booleanMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.7
   SINGLE-VALUE
   )

4.16.  printer-compression-supported

   ( 1.3.18.0.2.4.1128
   NAME 'printer-compression-supported'
   DESC 'Comma-delimited list of compression algorithms supported by
         this Printer.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   )

   For example:

      'none'
      'deflate,gzip'

   Note: Length overflow in values of this attribute MUST be handled by
   multiple instances of this attribute, i.e., individual
   comma-delimited list members MUST NOT be truncated.

   Note: For compatibility with IPP/1.1 [RFC2911], values of this
   attribute SHOULD NOT exceed 255 octets in length.

   Values defined in IPP/1.1 [RFC2911] and recorded in the IANA IPP
   registry [IANAIPP] include:

      'none' (no compression is used)
      'deflate' (public domain ZIP described in [RFC1951])
      'gzip' (GNU ZIP described in [RFC1952])
      'compress' (UNIX compression described in [RFC1977])

4.17.  printer-pages-per-minute

   ( 1.3.18.0.2.4.1127
   NAME 'printer-pages-per-minute'
   DESC 'The nominal number of pages per minute that can be output by
         this Printer.'
   EQUALITY integerMatch
   ORDERING integerOrderingMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.27
   SINGLE-VALUE
   )

   This attribute is informative, not a service guarantee.  Typically,
   it is the value used in marketing literature to describe this Printer
   -- for example, the value for a simplex or black-and-white print
   mode.

4.18.  printer-pages-per-minute-color

   ( 1.3.18.0.2.4.1126
   NAME 'printer-pages-per-minute-color'
   DESC 'The nominal number of color pages per minute that can be
         output by this Printer.'
   EQUALITY integerMatch
   ORDERING integerOrderingMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.27
   SINGLE-VALUE
   )

   This attribute is informative, not a service guarantee.  Typically,
   it is the value used in marketing literature to describe this
   Printer.

4.19.  printer-finishings-supported

   ( 1.3.18.0.2.4.1125
   NAME 'printer-finishings-supported'
   DESC 'Comma-delimited list of finishing operations supported by
         this Printer.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   )

   For example:

      'staple'
      'staple,punch,bind'

   Note: Length overflow in values of this attribute MUST be handled by
   multiple instances of this attribute, i.e., individual
   comma-delimited list members MUST NOT be truncated.

   Note: For compatibility with IPP/1.1 [RFC2911], values of this
   attribute SHOULD NOT exceed 255 octets in length.

   Values defined in IPP/1.1 [RFC2911] and recorded in the IANA IPP
   registry [IANAIPP] include:

      'none', 'staple', 'punch', 'cover', 'bind', 'saddle-stitch',
      'edge-stitch', 'staple-top-left', 'staple-bottom-left',
      'staple-top-right', 'staple-bottom-right', 'edge-stitch-left',
      'edge-stitch-top', 'edge-stitch-right', 'edge-stitch-bottom',
      'staple-dual-left', 'staple-dual-top', 'staple-dual-right',
      'staple-dual-bottom'.

   Note: Implementations MAY support other values.

4.20.  printer-number-up-supported

   ( 1.3.18.0.2.4.1124
   NAME 'printer-number-up-supported'
   DESC 'Maximum number of print-stream pages that can be imposed upon
         a single side of an instance of a selected medium by this
         Printer.'
   EQUALITY integerMatch
   ORDERING integerOrderingMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.27
   SINGLE-VALUE
   )

   For example:

      '1'
      '4'

   Note: Values of this attribute differ from the corresponding IPP
   attribute, in that only the maximum number-up is mapped from the
   corresponding IPP attribute 'number-up-supported' defined in
   [RFC2911].

4.21.  printer-sides-supported

   ( 1.3.18.0.2.4.1123
   NAME 'printer-sides-supported'
   DESC 'Comma-delimited list of impression sides (one or two) and the
         two-sided impression rotations supported by this Printer.'
   EQUALITY caseIgnoreMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   )

   For example:

      'one-sided'
      'one-sided,two-sided-short-edge'

   Note: Length overflow in values of this attribute MUST be handled by
   multiple instances of this attribute, i.e., individual
   comma-delimited list members MUST NOT be truncated.

   Note: For compatibility with IPP/1.1 [RFC2911], values of this
   attribute SHOULD NOT exceed 255 octets in length.

   Values defined in IPP/1.1 [RFC2911] and recorded in the IANA IPP
   registry [IANAIPP] are:

      'one-sided'
      'two-sided-long-edge'
      'two-sided-short-edge'

4.22.  printer-media-supported

   ( 1.3.18.0.2.4.1122
   NAME 'printer-media-supported'
   DESC 'One of the names/sizes/types/colors of the media supported by
         this Printer.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   )

   Values SHOULD conform to "PWG Media Standardized Names 2.0 (MSN2)"
   [PWG5101.1].

   Note: For compatibility with IPP/1.1 [RFC2911], values of this
   attribute SHOULD NOT exceed 255 octets in length.

   Values of standardized media size names defined in [PWG5101.1] and
   recorded in the IANA IPP registry [IANAIPP] include:

      'na_letter_8.5x11in'
      'iso_a4_210x297mm'

   Values of standardized media types defined in [PWG5101.1] and
   recorded in the IANA IPP registry [IANAIPP] include:

      'envelope'
      'stationery'

   Values of standardized media colors defined in [PWG5101.1] and
   recorded in the IANA IPP registry [IANAIPP] include:

      'white'
      'blue'

   Note: Multiple values for this attribute are represented as multiple
   instances of this attribute.

4.23.  printer-media-local-supported

   ( 1.3.18.0.2.4.1117
   NAME 'printer-media-local-supported'
   DESC 'One of the site-specific media supported by this Printer.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   )

   Values SHOULD conform to "PWG Media Standardized Names 2.0 (MSN2)"
   [PWG5101.1].

   For example:

      'custom_purchasing-form_8.5x11in' (site-specific name)

   Note: Multiple values for this attribute are represented as multiple
   instances of this attribute.

   Note: For compatibility with IPP/1.1 [RFC2911], values of this
   attribute SHOULD NOT exceed 255 octets in length.

4.24.  printer-resolution-supported

   ( 1.3.18.0.2.4.1121
   NAME 'printer-resolution-supported'
   DESC 'One of the resolutions supported for printing documents by
         this Printer.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   )

   Each resolution value MUST be a string containing three fields:

   1) Cross-feed direction resolution (positive integer);

   2) Feed direction resolution (positive integer);

   3) Unit -- 'dpi' (dots per inch) or 'dpcm' (dots per centimeter).

   Each resolution field MUST be delimited by '>', with optional
   trailing whitespace.  For example:

      '300> 300> dpi>'
      '600> 600> dpi>'
   Note: See the note in Section 4 about the different field delimiters
   used in the printer-xri-supported and printer-resolution-supported
   attributes ('<' and '>', respectively), chosen for compatibility with
   the IANA-registered SLP 'service:printer:' v2.0 template [SLPPRT20].

   Note: Multiple values for this attribute are represented as multiple
   instances of this attribute.

   Note: This attribute is based on 'printer-resolution-supported'
   defined in IPP/1.1 [RFC2911] with a complex encoding derived from
   'prtMarkerAddressabilityFeedDir', 'prtMarkerAddressabilityXFeedDir',
   and 'prtMarkerAddressabilityUnit' defined in "Printer MIB v2"
   [RFC3805] (which have integer encodings).

   Note: The syntax and delimiter for this attribute are aligned with
   the equivalent attribute in the 'service:printer:' v2.0 template
   [SLPPRT20].  Whitespace is permitted after (but not before) the
   delimiter '>'.

4.25.  printer-print-quality-supported

   ( 1.3.18.0.2.4.1120
   NAME 'printer-print-quality-supported'
   DESC 'Comma-delimited list of print qualities supported
         for printing documents on this Printer.'
   EQUALITY caseIgnoreMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   )

   For example:

      'unknown'
      'draft,normal,high'

   Note: Length overflow in values of this attribute MUST be handled by
   multiple instances of this attribute, i.e., individual
   comma-delimited list members MUST NOT be truncated.

   Values defined in IPP/1.1 [RFC2911] and recorded in the IANA IPP
   registry [IANAIPP] include:

      'draft'
      'normal'
      'high'

   Note: The value 'unknown' MUST only be reported if the corresponding
   IPP attribute is not present, i.e., the value 'unknown' is an
   artifact of this LDAP mapping.

4.26.  printer-job-priority-supported

   ( 1.3.18.0.2.4.1110
   NAME 'printer-job-priority-supported'
   DESC 'Indicates the number of job priority levels supported by
         this Printer.'
   EQUALITY integerMatch
   ORDERING integerOrderingMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.27
   SINGLE-VALUE
   )

   An IPP/1.1 [RFC2911] conformant Printer, which supports job priority,
   always supports a full range of priorities from '1' to '100' (to
   ensure consistent behavior); therefore, this attribute describes the
   'granularity' of priority supported.  Values of this attribute are
   from '1' to '100'.

4.27.  printer-copies-supported

   ( 1.3.18.0.2.4.1118
   NAME 'printer-copies-supported'
   DESC 'The maximum number of copies of a document that can be printed
         as a single job on this Printer.'
   EQUALITY integerMatch
   ORDERING integerOrderingMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.27
   SINGLE-VALUE
   )

   A positive value indicates the maximum supported copies.  A value of
   '0' indicates no maximum limit.  A value of '-1' indicates 'unknown'.

   Note: The syntax and values for this attribute are aligned with the
   equivalent attribute in the 'service:printer:' v2.0 template
   [SLPPRT20].

4.28.  printer-job-k-octets-supported

   ( 1.3.18.0.2.4.1111
   NAME 'printer-job-k-octets-supported'
   DESC 'The maximum size of an incoming print job that this Printer
         will accept, in kilobytes (1,024 octets).'
   EQUALITY integerMatch
   ORDERING integerOrderingMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.27
   SINGLE-VALUE
   )

   A positive value indicates the maximum supported job size.  A value
   of '0' indicates no maximum limit.  A value of '-1' indicates
   'unknown'.

   Note: The syntax and values for this attribute are aligned with the
   equivalent attribute in the 'service:printer:' v2.0 template
   [SLPPRT20].

4.29.  printer-current-operator

   ( 1.3.18.0.2.4.1112
   NAME 'printer-current-operator'
   DESC 'The identity of the current human operator responsible for
         operating this Printer.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   SINGLE-VALUE
   )

   The value of this attribute SHOULD include information that would
   enable other humans to reach the operator, such as a telephone
   number.

   Note: For interoperability and consistent text display, values of
   this attribute (a) SHOULD be normalized as recommended in "Unicode
   Format for Network Interchange" [RFC5198]; (b) SHOULD NOT contain DEL
   or any C0 or C1 control characters except for HT, CR, and LF; and
   (c) SHOULD only contain CR and LF characters together (not as
   singletons).

4.30.  printer-service-person

   ( 1.3.18.0.2.4.1113
   NAME 'printer-service-person'
   DESC 'The identity of the current human service person responsible
         for servicing this Printer.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   SINGLE-VALUE
   )

   The value of this attribute SHOULD include information that would
   enable other humans to reach the service person, such as a telephone
   number.

   Note: For interoperability and consistent text display, values of
   this attribute (a) SHOULD be normalized as recommended in "Unicode
   Format for Network Interchange" [RFC5198]; (b) SHOULD NOT contain DEL
   or any C0 or C1 control characters except for HT, CR, and LF; and
   (c) SHOULD only contain CR and LF characters together (not as
   singletons).

4.31.  printer-delivery-orientation-supported

   ( 1.3.18.0.2.4.1114
   NAME 'printer-delivery-orientation-supported'
   DESC 'Comma-delimited list of delivery orientations of pages as they
         are printed and ejected supported by this Printer.'
   EQUALITY caseIgnoreMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   )

   For example:

      'unknown'
      'face-up,face-down'

   Values defined in "Printer MIB v2" [RFC3805] for
   prtOutputPageDeliveryOrientation are:

      'face-up'
      'face-down'

   Note: The value 'unknown' MUST only be reported if the corresponding
   Printer MIB attribute is not present, i.e., the value 'unknown' is an
   artifact of this LDAP mapping.

   Note: The syntax and values for this attribute are aligned with the
   equivalent attribute in the 'service:printer:' v2.0 template
   [SLPPRT20].

4.32.  printer-stacking-order-supported

   ( 1.3.18.0.2.4.1115
   NAME 'printer-stacking-order-supported'
   DESC 'Comma-delimited list of stacking orders of pages as they are
         printed and ejected supported by this Printer.'
   EQUALITY caseIgnoreMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   )

   For example:

      'unknown'
      'first-to-last'
      'first-to-last,last-to-first'

   Values defined in "Printer MIB v2" [RFC3805] for
   prtOutputStackingOrder are:

      'first-to-last'
      'last-to-first'

   Note: The value 'unknown' MUST only be reported if the corresponding
   Printer MIB attribute is not present, i.e., the value 'unknown' is an
   artifact of this LDAP mapping.

   Note: The syntax and values for this attribute are aligned with the
   equivalent attribute in the 'service:printer:' v2.0 template
   [SLPPRT20].

4.33.  printer-output-features-supported

   ( 1.3.18.0.2.4.1116
   NAME 'printer-output-features-supported'
   DESC 'Comma-delimited list of output features supported by
         this Printer.'
   EQUALITY caseIgnoreMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   )

   For example:

      'unknown'
      'bursting,decollating'
      'offset-stacking'

   Note: Length overflow in values of this attribute MUST be handled by
   multiple instances of this attribute, i.e., individual
   comma-delimited list members MUST NOT be truncated.

   Values defined in "Printer MIB v2" [RFC3805] for prtOutputBursting,
   prtOutputDecollating, prtOutputPageCollated, and
   prtOutputOffsetStacking are:

      'bursting'
      'decollating'
      'page-collating'
      'offset-stacking'

   Note: The value 'unknown' MUST only be reported if the corresponding
   Printer MIB attributes are not present, i.e., the value 'unknown' is
   an artifact of this LDAP mapping.

   Note: The syntax and values for this attribute are aligned with the
   equivalent attribute in the 'service:printer:' v2.0 template
   [SLPPRT20].

   Note: Implementations MAY support other values.

4.34.  printer-aliases

   ( 1.3.18.0.2.4.1108
   NAME 'printer-aliases'
   DESC 'One of the site-specific administrative names of this Printer
         in addition to the value specified for printer-name.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   )

   Values of this attribute SHOULD be specified in the language
   specified in printer-natural-language-configured (for example, to
   support text-to-speech conversions), although the Printer's alias MAY
   be specified in any language.

   Note: Multiple values for this attribute are represented as multiple
   instances of this attribute.

   Note: For compatibility with IPP/1.1 [RFC2911], values of this
   attribute SHOULD NOT exceed 255 octets in length.

   Note: For interoperability, values of this attribute (a) SHOULD be
   normalized as recommended in "Unicode Format for Network Interchange"
   [RFC5198]; and (b) SHOULD NOT contain DEL or any C0 or C1 control
   characters.

4.35.  printer-device-id

   ( 1.3.18.0.2.24.46.1.101
   NAME 'printer-device-id'
   DESC 'The IEEE 1284 Device ID for this Printer.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   SINGLE-VALUE
   )

   Values of this attribute SHOULD conform to "PWG Command Set Format
   for IEEE 1284 Device ID v1.0" [PWG5107.2].

   Note: For compatibility with [PWG5100.14] and [PWG5107.2], values of
   this attribute SHOULD NOT exceed 1023 octets in length.

4.36.  printer-device-service-count

   ( 1.3.18.0.2.24.46.1.102
   NAME 'printer-device-service-count'
   DESC 'The number of Printer (print service) instances configured on
         this Imaging Device (host system).'
   EQUALITY integerMatch
   ORDERING integerOrderingMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.27
   SINGLE-VALUE
   )

   A positive value indicates the number of Printer (print service)
   instances.  A value of '-1' indicates 'unknown'.  A value of '0' is
   not meaningful (because this attribute must be reported by some
   Printer instance).

   Note: The syntax and values for this attribute are aligned with the
   equivalent 'device-service-count' attribute defined in [PWG5100.13].

4.37.  printer-uuid

   ( 1.3.18.0.2.24.46.1.104
   NAME 'printer-uuid'
   DESC 'A URN specifying the UUID of this Printer (print service)
         instance on this Imaging Device (host system).'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   SINGLE-VALUE
   )

   For example:

      'urn:uuid:f81d4fae-7dec-11d0-a765-00a0c91e6bf6'

   Values of this attribute MUST conform to the Universally Unique
   Identifier (UUID) URN namespace [RFC4122].

   Note: For compatibility with [PWG5100.13] and [RFC4122], values of
   this attribute SHOULD NOT exceed 45 octets in length.

   Note: LDAP application clients SHOULD NOT attempt to use malformed
   URN values read from this attribute.  LDAP administrative clients
   SHOULD NOT write malformed URN values into this attribute.

   Note: The syntax and values for this attribute are aligned with the
   equivalent 'printer-uuid' attribute defined in [PWG5100.13].

4.38.  printer-charge-info

   ( 1.3.18.0.2.24.46.1.105
   NAME 'printer-charge-info'
   DESC 'Descriptive information about paid printing services for this
         Printer.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   SINGLE-VALUE
   )

   For example:

      'This Printer can be used for paid printing at 2 cents/page.'

   Note: For compatibility with [PWG5100.13], values of this attribute
   SHOULD NOT exceed 1023 octets in length.

   Note: For interoperability and consistent text display, values of
   this attribute (a) SHOULD be normalized as recommended in "Unicode
   Format for Network Interchange" [RFC5198]; (b) SHOULD NOT contain any
   C0 or C1 control characters except for HT, CR, and LF; and (c) SHOULD
   only contain CR and LF characters together (not as singletons).

   Note: The syntax and values for this attribute are aligned with the
   equivalent 'printer-charge-info' attribute defined in [PWG5100.13].

4.39.  printer-charge-info-uri

   ( 1.3.18.0.2.24.46.1.106
   NAME 'printer-charge-info-uri'
   DESC 'A URI for a human-readable Web page for paid printing services
         for this Printer.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   SINGLE-VALUE
   )

   For example:

      'http://example.com/charges'

   See [STD66] for details of URI syntax.

   Note: For compatibility with IPP/1.1 [RFC2911] and [PWG5100.13],
   values of this attribute SHOULD NOT exceed 1023 octets in length.

   Note: LDAP application clients SHOULD NOT attempt to use malformed
   URI values read from this attribute.  LDAP administrative clients
   SHOULD NOT write malformed URI values into this attribute.

   Note: The syntax and values for this attribute are aligned with the
   equivalent 'printer-charge-info-uri' attribute defined in
   [PWG5100.13].

4.40.  printer-geo-location

   ( 1.3.18.0.2.24.46.1.107
   NAME 'printer-geo-location'
   DESC 'A geo: URI specifying the geographic location of this Printer.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   SINGLE-VALUE
   )

   For example:

      'geo:13.4125,103.8667'

   Values of this attribute MUST conform to the 'geo' URI scheme
   [RFC5870].

   Note: For compatibility with IPP/1.1 [RFC2911] and [PWG5100.13],
   values of this attribute SHOULD NOT exceed 1023 octets in length.

   Note: LDAP application clients SHOULD NOT attempt to use malformed
   URI values read from this attribute.  LDAP administrative clients
   SHOULD NOT write malformed URI values into this attribute.

   Note: The syntax and values for this attribute are aligned with the
   equivalent 'printer-geo-location' attribute defined in [PWG5100.13].

4.41.  printer-ipp-features-supported

   ( 1.3.18.0.2.24.46.1.108
   NAME 'printer-ipp-features-supported'
   DESC 'Comma-delimited list of IPP protocol features that
         this Printer supports.'
   EQUALITY caseIgnoreMatch
   SUBSTR caseIgnoreSubstringsMatch
   SYNTAX  1.3.6.1.4.1.1466.115.121.1.15
   )

   For example:

      'none'
      'unknown'
      'proof-print'
      'ipp-everywhere,proof-print,job-save'

   Note: Length overflow in values of this attribute MUST be handled by
   multiple instances of this attribute, i.e., individual
   comma-delimited list members MUST NOT be truncated.

   Values of this attribute SHOULD specify only IANA-registered keywords
   for the 'ipp-features-supported' attribute defined in [PWG5100.13] or
   other Standards Track IETF or IEEE-ISTO PWG specifications if this
   Printer implementation meets all of the IPP feature-specific
   conformance requirements.

   IANA-registered values include:

      'none' (No extension features are supported)
      'document-object' (Document object defined in [PWG5100.5])
      'job-save' (Job save defined in [PWG5100.11])
      'ipp-everywhere' ("IPP Everywhere" defined in [PWG5100.14])
      'page-overrides' (Page overrides defined in [PWG5100.6])
      'proof-print' (Proof print defined in [PWG5100.11])
      'subscription-object' (Subscription object defined in [RFC3995])

   Note: The value 'unknown' MUST only be reported if the corresponding
   IPP Printer attribute is not present, i.e., the value 'unknown' is an
   artifact of this LDAP mapping.

   Note: The syntax and values for this attribute are aligned with the
   equivalent 'ipp-features-supported' attribute defined in
   [PWG5100.13].

5.  Definition of Syntaxes

   No new attribute syntaxes are defined by this document.

   The attribute types defined in Section 4 of this document reference
   syntax OIDs defined in Section 3 of [RFC4517], which are summarized
   below:

   Syntax OID                      Syntax Description
   ------------------------------  -------------------------------
   1.3.6.1.4.1.1466.115.121.1.7    Boolean
   1.3.6.1.4.1.1466.115.121.1.15   DirectoryString (UTF-8 [STD63])
   1.3.6.1.4.1.1466.115.121.1.27   Integer

6.  Definition of Matching Rules

   No new matching rules are defined by this document.

   The attribute types defined in Section 4 of this document reference
   matching rules defined in Section 4 of [RFC4517], which are
   summarized below:

   Matching Rule OID               Matching Rule Name          Usage
   -----------------------------   ------------------          --------
   2.5.13.13                       booleanMatch                EQUALITY
   2.5.13.2                        caseIgnoreMatch             EQUALITY
   2.5.13.14                       integerMatch                EQUALITY
   2.5.13.15                       integerOrderingMatch        ORDERING
   2.5.13.4                        caseIgnoreSubstringsMatch   SUBSTR

7.  IANA Considerations

   This document does not define any new syntaxes or matching rules.

   This document defines a few new attribute types that have been
   registered by IANA per this document (see Section 7.1 below).

   All of the object classes and most of the attribute types described
   in this document were registered by IANA when RFC 3712 was published
   (see Section 7.2 below).

7.1.  Registration of Attribute Types

   The following Attribute Type OIDs have been assigned by the IEEE-ISTO
   PWG (see Section 1.3.2) and have been registered by IANA.

   Subject:  Request for Object Identifier Descriptor Registration

   Descriptor (short name):  see table below

   Object Identifier:  see table below

   Person & email address to contact for further information:  see below

   Usage:  attribute type

   Specification:  RFC 7612 (this document)

   Author/Change Controller:

      Ira McDonald
      High North Inc.
      221 Ridge Ave.
      Grand Marais, MI  49839
      United States
      Phone: +1 906-494-2434
      EMail: blueroofmusic@gmail.com

   Comments:

   Attribute Type                                OID
   ------------------------------------          ----------------------
   printer-device-id                             1.3.18.0.2.24.46.1.101
   printer-device-service-count                  1.3.18.0.2.24.46.1.102
   printer-uuid                                  1.3.18.0.2.24.46.1.104
   printer-charge-info                           1.3.18.0.2.24.46.1.105
   printer-charge-info-uri                       1.3.18.0.2.24.46.1.106
   printer-geo-location                          1.3.18.0.2.24.46.1.107
   printer-ipp-features-supported                1.3.18.0.2.24.46.1.108

7.2.  Object Classes and Attribute Types from RFC 3712

   This section is strictly informative.  None of the LDAP OIDs listed
   in this section have been re-registered by IANA.

   The following Object Class OIDs were assigned by IBM (see
   Section 1.3.1) and were already registered by IANA when RFC 3712 was
   published.

   Object Class                                  OID
   ------------------------------------          ----------------
   slpServicePrinter                             1.3.18.0.2.6.254
   printerAbstract                               1.3.18.0.2.6.258
   printerService                                1.3.18.0.2.6.255
   printerServiceAuxClass                        1.3.18.0.2.6.257
   printerIPP                                    1.3.18.0.2.6.256
   printerLPR                                    1.3.18.0.2.6.253

   The following Attribute Type OIDs were assigned by IBM (see
   Section 1.3.1) and were already registered by IANA when RFC 3712 was
   published.

   Attribute Type                                OID
   ------------------------------------          -----------------
   printer-uri                                   1.3.18.0.2.4.1140
   printer-xri-supported                         1.3.18.0.2.4.1107
   printer-name                                  1.3.18.0.2.4.1135
   printer-natural-language-configured           1.3.18.0.2.4.1119
   printer-location                              1.3.18.0.2.4.1136
   printer-info                                  1.3.18.0.2.4.1139
   printer-more-info                             1.3.18.0.2.4.1134
   printer-make-and-model                        1.3.18.0.2.4.1138
   printer-ipp-versions-supported                1.3.18.0.2.4.1133
   printer-multiple-document-jobs-supported      1.3.18.0.2.4.1132
   printer-charset-configured                    1.3.18.0.2.4.1109
   printer-charset-supported                     1.3.18.0.2.4.1131
   printer-generated-natural-language-supported  1.3.18.0.2.4.1137
   printer-document-format-supported             1.3.18.0.2.4.1130
   printer-color-supported                       1.3.18.0.2.4.1129
   printer-compression-supported                 1.3.18.0.2.4.1128
   printer-pages-per-minute                      1.3.18.0.2.4.1127
   printer-pages-per-minute-color                1.3.18.0.2.4.1126
   printer-finishings-supported                  1.3.18.0.2.4.1125
   printer-number-up-supported                   1.3.18.0.2.4.1124
   printer-sides-supported                       1.3.18.0.2.4.1123
   printer-media-supported                       1.3.18.0.2.4.1122
   printer-media-local-supported                 1.3.18.0.2.4.1117
   printer-resolution-supported                  1.3.18.0.2.4.1121
   printer-print-quality-supported               1.3.18.0.2.4.1120
   printer-job-priority-supported                1.3.18.0.2.4.1110
   printer-copies-supported                      1.3.18.0.2.4.1118
   printer-job-k-octets-supported                1.3.18.0.2.4.1111
   printer-current-operator                      1.3.18.0.2.4.1112
   printer-service-person                        1.3.18.0.2.4.1113
   printer-delivery-orientation-supported        1.3.18.0.2.4.1114
   printer-stacking-order-supported              1.3.18.0.2.4.1115
   printer-output-features-supported             1.3.18.0.2.4.1116
   printer-aliases                               1.3.18.0.2.4.1108

8.  Internationalization Considerations

   All text string attributes defined in this document of syntax
   'DirectoryString' [RFC4517] have values that are encoded in UTF-8
   [STD63], as required by [RFC4517].

   A language tag [BCP47] for all of the text string attributes defined
   in this document is contained in the
   printer-natural-language-configured attribute.

   Therefore, all object classes defined in this document conform to the
   IETF Policy on Character Sets and Languages [BCP18].

   Note: For interoperability and consistent text display, values of
   attributes defined in this document (a) SHOULD be normalized as
   recommended in "Unicode Format for Network Interchange" [RFC5198];
   (b) SHOULD NOT contain DEL or any C0 or C1 control characters except
   for HT, CR, and LF; (c) SHOULD only contain CR and LF characters
   together (not as singletons); and (d) SHOULD NOT contain HT, CR, or
   LF characters in names, e.g., printer-name and printer-aliases.

9.  Security Considerations

   See [RFC4513] for detailed guidance on authentication methods for
   LDAP and the use of TLS/1.2 [RFC5246] to supply connection
   confidentiality and data integrity for LDAP sessions.

   As with any LDAP schema, it is important to protect specific entries
   and attributes with the appropriate access control.  It is
   particularly important that only administrators can modify entries
   defined in this LDAP Printer schema.  Otherwise, an LDAP client might
   be fooled into diverting print service requests from the original
   Printer (or spooler) to a malicious intruder's host system, thus
   exposing the information in printed documents.

   Note: Security vulnerabilities can arise if DEL or any C0 or C1
   control characters are included in names, e.g., printer-name or
   printer-aliases.

   For additional security considerations regarding deploying Printers
   in an IPP environment, see Section 8 of [RFC2911].

10.  References

10.1.  Normative References

   [BCP47]      Phillips, A. and M. Davis, "Matching of Language Tags",
                BCP 47, RFC 4647, September 2006.

                Phillips, A., Ed., and M. Davis, Ed., "Tags for
                Identifying Languages", BCP 47, RFC 5646,
                September 2009.

                <http://www.rfc-editor.org/info/bcp47>

   [IANACHAR]   Internet Assigned Numbers Authority (IANA) registry
                "Character Sets",
                <http://www.iana.org/assignments/character-sets>.

   [IANAIPP]    Internet Assigned Numbers Authority (IANA) registry
                "Internet Printing Protocol (IPP) Registrations",
                <http://www.iana.org/assignments/ipp-registrations>.

   [IANAMIME]   Internet Assigned Numbers Authority (IANA) registry
                "Media Types", <http://www.iana.org/assignments/
                media-types/index.html>.

   [PWG5100.5]  Carney, D., Hastings, T., and P. Zehler, "IPP Document
                Object", PWG 5100.5-2003, October 2003,
                <http://www.pwg.org/standards.html>.

   [PWG5100.6]  Zehler, P., Herriot, R., and K. Ocke, "IPP Page
                Overrides", PWG 5100.6-2003, October 2003,
                <http://www.pwg.org/standards.html>.

   [PWG5100.11] Hastings, T. and D. Fullman, "IPP Job and Printer
                Extensions - Set 2 (JPS2)", PWG 5100.11-2010,
                October 2010, <http://www.pwg.org/standards.html>.

   [PWG5100.12] Bergman, R., Lewis, H., McDonald, I., and M. Sweet, "IPP
                Version 2.0 Second Edition (IPP/2.0 SE)",
                PWG 5100.12-2011, February 2011,
                <http://www.pwg.org/standards.html>.

   [PWG5100.13] Sweet, M., McDonald, I., and P. Zehler, "IPP Job and
                Printer Extensions - Set 3 (JPS3)", PWG 5100.13-2012,
                July 2012, <http://www.pwg.org/standards.html>.

   [PWG5100.14] Sweet, M., McDonald, I., Mitchell, A., and J. Hutchings,
                "IPP Everywhere", PWG 5100.14-2013, January 2013,
                <http://www.pwg.org/standards.html>.

   [PWG5101.1]  Sweet, M., Bergman, R., and T. Hastings, "PWG Media
                Standardized Names 2.0 (MSN2)", PWG 5101.1-2013,
                March 2013, <http://www.pwg.org/standards.html>.

   [PWG5107.2]  McDonald, I., "PWG Command Set Format for IEEE 1284
                Device ID v1.0", PWG 5107.2-2010, May 2010,
                <http://www.pwg.org/standards.html>.

   [RFC2119]    Bradner, S., "Key words for use in RFCs to Indicate
                Requirement Levels", BCP 14, RFC 2119,
                DOI 10.17487/RFC2119, March 1997,
                <http://www.rfc-editor.org/info/rfc2119>.

   [RFC2617]    Franks, J., Hallam-Baker, P., Hostetler, J., Lawrence,
                S., Leach, P., Luotonen, A., and L. Stewart, "HTTP
                Authentication: Basic and Digest Access Authentication",
                RFC 2617, DOI 10.17487/RFC2617, June 1999,
                <http://www.rfc-editor.org/info/rfc2617>.

   [RFC2707]    Bergman, R., Hastings, T., Isaacson, S., and H. Lewis,
                "Job Monitoring MIB - V1.0", RFC 2707,
                DOI 10.17487/RFC2707, November 1999,
                <http://www.rfc-editor.org/info/rfc2707>.

   [RFC2911]    Hastings, T., Ed., Herriot, R., deBry, R., Isaacson, S.,
                and P. Powell, "Internet Printing Protocol/1.1: Model
                and Semantics", RFC 2911, DOI 10.17487/RFC2911,
                September 2000,
                <http://www.rfc-editor.org/info/rfc2911>.

   [RFC2926]    Kempf, J., Moats, R., and P. St. Pierre, "Conversion of
                LDAP Schemas to and from SLP Templates", RFC 2926,
                DOI 10.17487/RFC2926, September 2000,
                <http://www.rfc-editor.org/info/rfc2926>.

   [RFC3510]    Herriot, R. and I. McDonald, "Internet Printing
                Protocol/1.1: IPP URL Scheme", RFC 3510,
                DOI 10.17487/RFC3510, April 2003,
                <http://www.rfc-editor.org/info/rfc3510>.

   [RFC3805]    Bergman, R., Lewis, H., and I. McDonald, "Printer
                MIB v2", RFC 3805, DOI 10.17487/RFC3805, June 2004,
                <http://www.rfc-editor.org/info/rfc3805>.

   [RFC3987]    Duerst, M. and M. Suignard, "Internationalized Resource
                Identifiers (IRIs)", RFC 3987, DOI 10.17487/RFC3987,
                January 2005, <http://www.rfc-editor.org/info/rfc3987>.

   [RFC3995]    Herriot, R. and T. Hastings, "Internet Printing Protocol
                (IPP): Event Notifications and Subscriptions", RFC 3995,
                DOI 10.17487/RFC3995, March 2005,
                <http://www.rfc-editor.org/info/rfc3995>.

   [RFC4122]    Leach, P., Mealling, M., and R. Salz, "A Universally
                Unique IDentifier (UUID) URN Namespace", RFC 4122,
                DOI 10.17487/RFC4122, July 2005,
                <http://www.rfc-editor.org/info/rfc4122>.

   [RFC4510]    Zeilenga, K., Ed., "Lightweight Directory Access
                Protocol (LDAP): Technical Specification Road Map",
                RFC 4510, DOI 10.17487/RFC4510, June 2006,
                <http://www.rfc-editor.org/info/rfc4510>.

   [RFC4513]    Harrison, R., Ed., "Lightweight Directory Access
                Protocol (LDAP): Authentication Methods and Security
                Mechanisms", RFC 4513, DOI 10.17487/RFC4513, June 2006,
                <http://www.rfc-editor.org/info/rfc4513>.

   [RFC4517]    Legg, S., Ed., "Lightweight Directory Access Protocol
                (LDAP): Syntaxes and Matching Rules", RFC 4517,
                DOI 10.17487/RFC4517, June 2006,
                <http://www.rfc-editor.org/info/rfc4517>.

   [RFC4524]    Zeilenga, K., Ed., "COSINE LDAP/X.500 Schema", RFC 4524,
                DOI 10.17487/RFC4524, June 2006,
                <http://www.rfc-editor.org/info/rfc4524>.

   [RFC5198]    Klensin, J. and M. Padlipsky, "Unicode Format for
                Network Interchange", RFC 5198, DOI 10.17487/RFC5198,
                March 2008, <http://www.rfc-editor.org/info/rfc5198>.

   [RFC5246]    Dierks, T. and E. Rescorla, "The Transport Layer
                Security (TLS) Protocol Version 1.2", RFC 5246,
                DOI 10.17487/RFC5246, August 2008,
                <http://www.rfc-editor.org/info/rfc5246>.

   [RFC5280]    Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
                Housley, R., and W. Polk, "Internet X.509 Public Key
                Infrastructure Certificate and Certificate Revocation
                List (CRL) Profile", RFC 5280, DOI 10.17487/RFC5280,
                May 2008, <http://www.rfc-editor.org/info/rfc5280>.

   [RFC5870]    Mayrhofer, A. and C. Spanring, "A Uniform Resource
                Identifier for Geographic Locations ('geo' URI)",
                RFC 5870, DOI 10.17487/RFC5870, June 2010,
                <http://www.rfc-editor.org/info/rfc5870>.

   [RFC6818]    Yee, P., "Updates to the Internet X.509 Public Key
                Infrastructure Certificate and Certificate Revocation
                List (CRL) Profile", RFC 6818, DOI 10.17487/RFC6818,
                January 2013, <http://www.rfc-editor.org/info/rfc6818>.

   [RFC7235]    Fielding, R., Ed., and J. Reschke, Ed., "Hypertext
                Transfer Protocol (HTTP/1.1): Authentication", RFC 7235,
                DOI 10.17487/RFC7235, June 2014,
                <http://www.rfc-editor.org/info/rfc7235>.

   [RFC7472]    McDonald, I. and M. Sweet, "Internet Printing Protocol
                (IPP) over HTTPS Transport Binding and the 'ipps' URI
                Scheme", RFC 7472, DOI 10.17487/RFC7472, March 2015,
                <http://www.rfc-editor.org/info/rfc7472>.

   [STD63]      Yergeau, F., "UTF-8, a transformation format of ISO
                10646", STD 63, RFC 3629, November 2003,
                <http://www.rfc-editor.org/info/std63>.

   [STD66]      Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
                Resource Identifier (URI): Generic Syntax", STD 66, RFC
                3986, January 2005,
                <http://www.rfc-editor.org/info/std66>.

10.2.  Informative References

   [BCP13]      Freed, N. and J. Klensin, "Multipurpose Internet Mail
                Extensions (MIME) Part Four: Registration Procedures",
                BCP 13, RFC 4289, December 2005.

                Freed, N., Klensin, J., and T. Hansen, "Media Type
                Specifications and Registration Procedures", BCP 13,
                RFC 6838, January 2013.

                <http://www.rfc-editor.org/info/bcp13>

   [BCP18]      Alvestrand, H., "IETF Policy on Character Sets and
                Languages", BCP 18, RFC 2277, January 1998,
                <http://www.rfc-editor.org/info/bcp18>.

   [BCP19]      Freed, N. and J. Postel, "IANA Charset Registration
                Procedures", BCP 19, RFC 2978, October 2000,
                <http://www.rfc-editor.org/info/bcp19>.

   [IANASLP]    Internet Assigned Numbers Authority (IANA) registry
                "Service Location Protocol, Version 2 (SLPv2)
                Templates",
                <http://www.iana.org/assignments/svrloc-templates/>.

   [RFC1179]    McLaughlin, L., "Line printer daemon protocol",
                RFC 1179, DOI 10.17487/RFC1179, August 1990,
                <http://www.rfc-editor.org/info/rfc1179>.

   [RFC1951]    Deutsch, P., "DEFLATE Compressed Data Format
                Specification version 1.3", RFC 1951,
                DOI 10.17487/RFC1951, May 1996,
                <http://www.rfc-editor.org/info/rfc1951>.

   [RFC1952]    Deutsch, P., "GZIP file format specification
                version 4.3", RFC 1952, DOI 10.17487/RFC1952, May 1996,
                <http://www.rfc-editor.org/info/rfc1952>.

   [RFC1977]    Schryver, V., "PPP BSD Compression Protocol", RFC 1977,
                DOI 10.17487/RFC1977, August 1996,
                <http://www.rfc-editor.org/info/rfc1977>.

   [RFC2079]    Smith, M., "Definition of an X.500 Attribute Type and an
                Object Class to Hold Uniform Resource Identifiers
                (URIs)", RFC 2079, DOI 10.17487/RFC2079, January 1997,
                <http://www.rfc-editor.org/info/rfc2079>.

   [RFC2566]    deBry, R., Hastings, T., Herriot, R., Isaacson, S., and
                P. Powell, "Internet Printing Protocol/1.0: Model and
                Semantics", RFC 2566, DOI 10.17487/RFC2566, April 1999,
                <http://www.rfc-editor.org/info/rfc2566>.

   [RFC2608]    Guttman, E., Perkins, C., Veizades, J., and M. Day,
                "Service Location Protocol, Version 2", RFC 2608,
                DOI 10.17487/RFC2608, June 1999,
                <http://www.rfc-editor.org/info/rfc2608>.

   [RFC2609]    Guttman, E., Perkins, C., and J. Kempf, "Service
                Templates and Service: Schemes", RFC 2609,
                DOI 10.17487/RFC2609, June 1999,
                <http://www.rfc-editor.org/info/rfc2609>.

   [RFC3712]    Fleming, P. and I. McDonald, "Lightweight Directory
                Access Protocol (LDAP): Schema for Printer Services",
                RFC 3712, DOI 10.17487/RFC3712, February 2004,
                <http://www.rfc-editor.org/info/rfc3712>.

   [RFC4559]    Jaganathan, K., Zhu, L., and J. Brezak, "SPNEGO-based
                Kerberos and NTLM HTTP Authentication in Microsoft
                Windows", RFC 4559, DOI 10.17487/RFC4559, June 2006,
                <http://www.rfc-editor.org/info/rfc4559>.

   [SLPPRT20]   St. Pierre, P., Isaacson, S., and I. McDonald,
                "Definition of the 'service:printer:' abstract type
                v2.0", May 2000.  Reviewed and approved by an IETF SLP
                Designated Expert, according to Section 5 ("IANA
                Considerations") of [RFC2609].  Archived in [IANASLP] as
                "printer.2.0.en".   IANA, "Service Location Protocol, Version 2 (SLPv2)
                Templates",
                <http://www.iana.org/assignments/svrloc-templates>.

Appendix A.  Changes since RFC 3712

   1) Added many editorial corrections and clarifications

      - corrected typos, missing words, and ambiguous sentences;

      - replaced lowercase 'printer' with titlecase 'Printer' for
        readability and consistency with IETF and IEEE-ISTO PWG IPP
        standards usage;

      - added implementation notes;

      - updated and added references.

   2) Deleted length restrictions from formal definitions of
      DirectoryString syntax attributes

      - replaced with notes recommending length restrictions for
        compatibility with existing implementations of [RFC3712] and
        underlying string length limits in [RFC2707], [RFC2911],
        [RFC3805], [PWG5107.2], [PWG5100.13], and [PWG5100.14].

   3) Added new Printer attributes defined in [PWG5107.2], [PWG5100.13],
      and [PWG5100.14] (see Section 7.1)

      - updated the table of Printer attributes and source documents in
        Section 4 ("Definition of Attribute Types");

      - added support for IEEE-ISTO PWG "IPP Everywhere" [PWG5100.14]
        project.

   4) Added implementation note to Section 4 about string encodings

      - added discussion of 'List of xxx' and 'One of xxx' encodings;

      - stated that any of these attributes can be represented as
        multiple instances (i.e., to avoid length overflow).

   5) Improved comma-delimited examples of string attributes

      - added both single-valued and multi-valued examples.

   6) Clarified use of printer-xri-supported and
      printer-resolution-supported attributes, and their corresponding
      field delimiters

      - added note in Section 4 ("Definition of Attribute Types") to
        explain the origin of the different field delimiters;

      - added examples to show optional *trailing* whitespace after '<'
        delimiters in printer-xri-supported;

      - added examples to show optional *trailing* whitespace after '>'
        delimiters in printer-resolution-supported.

   7) Clarified Section 8 ("Internationalization Considerations")

      - added note about Net-Unicode [RFC5198] and avoiding use of C0
        and C1 control characters.

   8) Clarified Section 9 ("Security Considerations")

      - added note about security vulnerabilities caused by use of DEL
        or any C0 or C1 control characters in names.

   9) Clarified terms and abbreviations

      - renamed Section 2 ("Conventions Used in This Document");

      - added Section 2.1 ("Requirements Language");

      - added Section 2.2 ("LDAP Schema Descriptions");

      - added Section 2.3 ("Abbreviations").

Acknowledgments

   The authors wish to acknowledge significant contributions from Ken
   Jones and Harry Lewis and excellent comments from Patrik Faltstrom,
   Ryan Moats, Robert Moore, Lee Rafalow, Kimberly Reger, and Kurt
   Zeilenga during the development of the original LDAP Printer schema
   [RFC3712].

   The authors wish to acknowledge excellent comments from Nevil
   Brownlee, Barry Leiba, Alexey Melnikov, Tom Petch, and Mike Sweet
   during the development of this current version of the LDAP Printer
   schema.

   Thanks to the members of the IEEE-ISTO PWG IPP Working Group, for
   their review comments and help in preparing this document.

Authors' Addresses

   Pat Fleming
   Independent
   51796 171 Ave.
   Pine Island, MN  55963
   United States

   Phone: +1 507-356-8277
   EMail: patfleminghtc@gmail.com

   Ira McDonald
   High North Inc.
   221 Ridge Ave.
   Grand Marais, MI  49839
   United States

   Phone: +1 906-494-2434
   EMail: blueroofmusic@gmail.com