draft-ietf-ipp-collection-04.txt   rfc3382.txt 
INTERNET-DRAFT Roger deBry Network Working Group R. deBry
<draft-ietf-ipp-collection-04.txt> Utah Valley State College Request for Comments: 3382 Utah Valley State College
Updates: 2910, 2911 R. Herriot
Category: Standards Track Consultant
T. Hastings T. Hastings
Xerox Corporation
R. Herriot
Xerox Corporation
K. Ocke K. Ocke
Xerox Corporation
P. Zehler P. Zehler
Xerox Corporation Xerox Corporation
January 24, 2001 September 2002
Internet Printing Protocol (IPP): Internet Printing Protocol (IPP):
The 'collection' attribute syntax The 'collection' attribute syntax
Copyright (C) The Internet Society (2001). All Rights Reserved.
Status of this Memo: Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of [RFC2026]. Internet-Drafts are
working documents of the Internet Engineering Task Force (IETF), its
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Internet-Drafts are draft documents valid for a maximum of six months This document specifies an Internet standards track protocol for the
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time. It is inappropriate to use Internet-Drafts as reference improvements. Please refer to the current edition of the "Internet
material or to cite them other than as "work in progress". Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
The list of current Internet-Drafts can be accessed at Copyright Notice
http://www.ietf.org/ietf/1id-abstracts.txt
The list of Internet-Draft Shadow Directories can be accessed as Copyright (C) The Internet Society (2002). All Rights Reserved.
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Abstract Abstract
This document specifies an OPTIONAL attribute syntax called
'collection' for use with the Internet Printing Protocol/1.0
(IPP) [RFC2565, RFC2566], IPP/1.1 [RFC2911, RFC2910], and
subsequent versions. A 'collection' is a container holding one or
more named values, which are called "member" attributes. A
collection allows data to be grouped like a PostScript dictionary
or a Java Map. This document also specifies the conformance
requirements for a definition document that defines a collection
attribute. Finally, this document gives some illustrative
example collection attribute definitions that are not intended as
actual attribute specifications.
The full set of IPP documents includes:
Design Goals for an Internet Printing Protocol [RFC2567]
Rationale for the Structure and Model and Protocol for the Internet
Printing Protocol [RFC2568]
Internet Printing Protocol/1.1: Model and Semantics [RFC2911]
Internet Printing Protocol/1.1: Encoding and Transport [RFC2910]
Internet Printing Protocol/1.1: Implementer's Guide [IPP-IIG]
Mapping between LPD and IPP Protocols [RFC2569]
The "Design Goals for an Internet Printing Protocol" document takes a
broad look at distributed printing functionality, and it enumerates
real-life scenarios that help to clarify the features that need to be
included in a printing protocol for the Internet. It identifies
requirements for three types of users: end users, operators, and
administrators. It calls out a subset of end user requirements that
are satisfied in IPP/1.0. A few OPTIONAL operator operations have
been added to IPP/1.1.
The "Rationale for the Structure and Model and Protocol for the
Internet Printing Protocol" document describes IPP from a high level
view, defines a roadmap for the various documents that form the suite
of IPP specification documents, and gives background and rationale
for the IETF working group's major decisions.
The "Internet Printing Protocol/1.1: Encoding and Transport" document
is a formal mapping of the abstract operations and attributes defined
in the model document onto HTTP/1.1 [RFC2616]. It defines the
encoding rules for a new Internet MIME media type called
"application/ipp". This document also defines the rules for
transporting over HTTP a message body whose Content-Type is
"application/ipp". This document defines a new scheme named 'ipp'
for identifying IPP printers and jobs.
The "Internet Printing Protocol/1.1: Implementer's Guide" document
gives insight and advice to implementers of IPP clients and IPP
objects. It is intended to help them understand IPP/1.1 and some of
the considerations that may assist them in the design of their client
and/or IPP object implementations. For example, a typical order of
processing requests is given, including error checking. Motivation
for some of the specification decisions is also included.
The "Mapping between LPD and IPP Protocols" document gives some This document specifies an OPTIONAL attribute syntax called
advice to implementers of gateways between IPP and LPD (Line Printer 'collection' for use with the Internet Printing Protocol (IPP/1.0 and
Daemon) implementations. IPP/1.1). A 'collection' is a container holding one or more named
values, which are called "member" attributes. A collection allows
data to be grouped like a PostScript dictionary or a Java Map. This
document also specifies the conformance requirements for a definition
document that defines a collection attribute. Finally, this document
gives some illustrative example collection attribute definitions that
are not intended as actual attribute specifications.
Table of Contents Table of Contents
1 Introduction....................................................5 1 Introduction.....................................................3
1.1 Problem Statement ............................................5 1.1 Problem Statement..............................................3
1.2 Solution .....................................................5 1.2 Solution.......................................................3
2 Terminology......................................................4
2 Terminology.....................................................6 2.1 Conformance Terminology........................................4
2.1 Conformance Terminology ......................................6 2.2 Other terminology..............................................5
2.2 Other terminology ............................................7 3 Definition of a Collection Attribute.............................5
3.1 Information to Include.........................................5
3 Definition of a Collection Attribute............................7 3.2 Nested Collections.............................................9
3.1 Information to Include .......................................7 4 Collection Attributes as Attributes in Operations................9
3.2 Nested Collections ..........................................11 4.1 General Rules..................................................9
4.2 Unsupported Values.............................................9
4 Collection Attributes as Attributes in Operations..............11 5 Example definition of a collection attribute.....................9
4.1 General Rules ...............................................11 5.1 media-col (collection)........................................10
4.2 Unsupported Values ..........................................11 5.1.1 media-color (type3 keyword | name(MAX)......................10
5.1.2 media-size (collection).....................................11
5 Example definition of a collection attribute...................12 5.2 media-col-default (collection)................................11
5.1 media-col (collection) ......................................12 5.3 media-col-ready (1setOf collection)...........................12
5.1.1media-color (type3 keyword | name(MAX) ......................13 5.4 media-col-supported (1setOf type2 keyword)....................12
5.1.2media-size (collection) .....................................13 6 A Second Example Definition Of A Collection Attribute...........12
5.2 media-col-default (collection) ..............................14 7 Encoding........................................................13
5.3 media-col-ready (1setOf collection) .........................14 7.1 Additional tags defined for representing a collection
5.4 media-col-supported (1setOf type2 keyword) ..................14 attribute value...............................................13
7.2 Example encoding: "media-col" (collection)....................14
6 A Second Example Definition Of A Collection Attribute..........15 8 Legacy issues...................................................20
9 IANA Considerations.............................................20
7 Encoding.......................................................15 10 Internationalization Considerations............................20
7.1 Additional tags defined for representing a collection attribute 11 Security Considerations........................................21
value16 12 References.....................................................21
7.2 Example encoding: "media-col" (collection) ..................17 Appendix A: Encoding Example of a Simple Collection (Informative).22
Appendix B: Encoding Example of 1setOf Collection (Informative)...25
8 Legacy issues..................................................23 Appendix C: Encoding Example of Collection containing 1setOf XXX
attribute (Informative)...............................31
9 IANA Considerations............................................23 Appendix D: Description of the Base IPP Documents (Informative)...35
9.1 Attribute Syntax Registration ...............................23 Authors' Addresses................................................36
Full Copyright Statement..........................................38
10 Internationalization Considerations............................23
11 Security Considerations........................................24
12 References.....................................................24
13 Author's Addresses.............................................25
14 Appendix A: Encoding Example of a Simple Collection............26
15 Appendix B: Encoding Example of 1setOf Collection..............29
16 Appendix C: Encoding Example of Collection containing 1setOf XXX
attribute.........................................................34
17 Appendix D: Full Copyright Statement...........................38
Table of Tables Table of Tables
Table 1 - "media-col" member attributes...........................13 Table 1 - "media-col" member attributes...........................10
Table 2 - "media-size" collection member attributes...............13 Table 2 - "media-size" collection member attributes...............11
Table 3 - Tags defined for encoding the 'collection' attribute syntax Table 3 - Tags defined for encoding the 'collection' attribute
..............................................................16 syntax .................................................13
Table 4 - Overview Encoding of "media-col" collection.............18 Table 4 - Overview Encoding of "media-col" collection.............15
Table 5 - Example Encoding of "media-col" collection..............18 Table 5 - Example Encoding of "media-col" collection..............16
Table 6 - Overview Encoding of simple collection..................26 Table 6 - Overview Encoding of simple collection..................22
Table 7 - Example Encoding of simple collection...................26 Table 7 - Example Encoding of simple collection...................22
Table 8 - Overview Encoding of 1setOf collection..................29 Table 8 - Overview Encoding of 1setOf collection..................25
Table 9 - Example Encoding of 1setOf collection...................30 Table 9 - Example Encoding of 1setOf collection...................26
Table 10 - Overview Encoding of collection with 1setOf value......34 Table 10 - Overview Encoding of collection with 1setOf value......31
Table 11 - Example Encoding of collection with 1setOf value.......35 Table 11 - Example Encoding of collection with 1setOf value.......32
1 Introduction 1 Introduction
This document is an OPTIONAL extension to IPP/1.0 [RFC2565, RFC2566]
and IPP/1.1 [RFC2911, RFC2910]. For a description of the base IPP
documents see Appendix D.
1.1 Problem Statement 1.1 Problem Statement
The IPP Model and Semantics [RFC2911] supports most of the common The IPP Model and Semantics [RFC2911] supports most of the common
data structures that are available in programming languages. It lacks data structures that are available in programming languages. It
a mechanism for grouping several attributes of different types. The lacks a mechanism for grouping several attributes of different types.
Java language uses the Map to solve this problem and PostScript has a The Java language uses the Map to solve this problem and PostScript
dictionary. The new mechanism for grouping attributes together has a dictionary. The new mechanism for grouping attributes together
(called 'collection' mechanism) must allow for optional members and (called 'collection' mechanism) must allow for optional members and
subsequent addition of new members. the subsequent addition of new members.
The 'collection' mechanism must be encoded in a manner consistent The 'collection' mechanism must be encoded in a manner consistent
with existing 1.0 and 1.1 parsing rules (see [RFC2910]). Current 1.0 with existing 1.0 and 1.1 parsing rules (see [RFC2910]). Current 1.0
and 1.1 parsers that don't support the 'collection' mechanism must and 1.1 parsers that don't support the 'collection' mechanism must
not confuse collections or parts of collection they receive with not confuse collections or parts of a collection they receive with
other attributes. other attributes.
1.2 Solution 1.2 Solution
The new mechanism is a new IPP attribute syntax called a The new mechanism is a new IPP attribute syntax called a
'collection'. As such, each collection value is a value of an 'collection'. As such, each collection value is a value of an
attribute whose attribute syntax type is defined to be a attribute whose attribute syntax type is defined to be a
'collection'. Such an attribute is called a collection attribute. 'collection'. Such an attribute is called a collection attribute.
The name of the collection attribute serves to identify the The name of the collection attribute serves to identify the
collection value in an operation request or response, as with any collection value in an operation request or response, as with any
attribute value. attribute value.
The 'collection' attribute syntax is a container holding one or more The 'collection' attribute syntax is a container holding one or more
named values (i.e., attributes), which are called member attributes. named values (i.e., attributes), which are called member attributes.
Each collection attribute definition document lists the mandatory and Each collection attribute definition document lists the mandatory and
optional member attributes of each collection value. A collection optional member attributes of each collection value. A collection
value is similar to an IPP attribute group in a request or a value is similar to an IPP attribute group in a request or a
response, such as the operation attributes group. They both consist response, such as the operation attributes group. They both consist
of a set of attributes. of a set of attributes.
As with any attribute syntax, the document that defines a collection As with any attribute syntax, the document that defines a collection
attribute specifies whether the attribute is single-value attribute specifies whether the attribute is single-valued
(collection) or multi-valued (1setOf collection). If the attribute is (collection) or multi-valued (1setOf collection). If the attribute
multi-valued (1setOf collection) each collection value MUST be a is multi-valued (1setOf collection), each collection value MUST be a
separate instance of a single definition of a collection, i.e. it separate instance of a single definition of a collection, i.e., it
MUST have the same member attributes except for OPTIONAL member MUST have the same member attributes except for OPTIONAL member
attributes. If we view each collection definition as a separate attributes. If we view each collection definition as a separate
syntax type, this rule continues the IPP/1.1 notion that each syntax type, this rule continues the IPP/1.1 notion that each
attribute has a single type or pattern (e.g. "keyword | name" is a attribute has a single type or pattern (e.g., "keyword | name" is a
pattern). Without this rule, the supported values would be more pattern). Without this rule, the supported values would be more
difficult to describe and the mechanism defined in item 4 of section difficult to describe and the mechanism defined in item 4 of section
3.1 would not be sufficient. 3.1 would not be sufficient.
The name of each member attribute MUST be unique for a collection The name of each member attribute MUST be unique for a collection
attribute, but MAY be the same as the name of a member attribute in attribute, but MAY be the same as the name of a member attribute in
another collection attribute and/or MAY be the same as the name of an another collection attribute and/or MAY be the same as the name of an
attribute that is not a member of a collection. The rules for naming attribute that is not a member of a collection. The rules for naming
member attributes are given in section 3.1. member attributes are given in section 3.1.
Each member attribute can have any attribute syntax type, including Each member attribute can have any attribute syntax type, including
'collection', and can be either single-valued or multi-valued. The 'collection', and can be either single-valued or multi-valued. The
length of a collection value is not limited. However, the length of length of a collection value is not limited. However, the length of
each member attribute MUST NOT exceed the limit of its attribute each member attribute MUST NOT exceed the limit of its attribute
syntax. syntax.
The member attributes in a collection MAY be in any order in a The member attributes in a collection MAY be in any order in a
request or response. When a client sends a collection attribute to request or response. When a client sends a collection attribute to
the Printer, the order that the Printer stores the member attributes the Printer, the order that the Printer stores the member attributes
of the collection value and the order returned in a response MAY be of the collection value and the order returned in a response MAY be
different from the order sent by the client. different from the order sent by the client.
A collection value MUST NOT contains two or more member attributes A collection value MUST NOT contain two or more member attributes
with the same attribute name. Such a collection is mal-formed. with the same attribute name. Such a collection is mal-formed.
Clients MUST NOT submit such malformed requests and Printers MUST NOT Clients MUST NOT submit such malformed requests and Printers MUST NOT
return such malformed responses. If such a malformed request is return such malformed responses. If such a malformed request is
submitted to a Printer, the Printer MUST (depending on submitted to a Printer, the Printer MUST (depending on
implementation) either (1) reject the request with the 'client-error- implementation) either (1) reject the request with the 'client-
bad-request' status code (see section 13.1.4.1), or (2) accept the error-bad-request' status code (see [RFC2911] section 13.1.4.1), or
request and use only one of each duplicate member attribute. (2) accept the request and use only one of each duplicate member
attributes.
2 Terminology 2 Terminology
This section defines terminology used throughout this document. This section defines terminology used throughout this document.
2.1 Conformance Terminology 2.1 Conformance Terminology
Capitalized terms, such as MUST, MUST NOT, REQUIRED, SHOULD, SHOULD Capitalized terms, such as MUST, MUST NOT, REQUIRED, SHOULD, SHOULD
NOT, MAY, NEED NOT, and OPTIONAL, have special meaning relating to NOT, MAY, NEED NOT, and OPTIONAL, have special meaning relating to
conformance. These terms are defined in [RFC2911] section 12.1 on conformance as defined in BCP 14, RFC 2119 [RFC2119] and [RFC2911],
conformance terminology, most of which is taken from RFC 2119 section 12.1. If an implementation supports the extension defined in
[RFC2119]. this document, then these terms apply; otherwise, they do not. These
terms define conformance to this document only; they do not affect
The following specialization of these terms apply to this document: conformance to other documents, unless explicitly stated otherwise.
REQUIRED: if an implementation supports the extensions described in
this document, it MUST support a REQUIRED feature.
OPTIONAL: if an implementation supports the extensions described in
this document, it MAY support an OPTIONAL feature.
2.2 Other terminology 2.2 Other terminology
This document uses terms such as Job object (or Job), IPP Printer This document uses terms such as Job object (or Job), IPP Printer
object (or Printer), "operation", "request", response", "attributes", object (or Printer), "operation", "request", response", "attributes",
"keywords", and "support". These terms have special meaning and are "keywords", and "support". These terms have special meaning and are
defined in the model terminology [RFC2911] section 12.2. The defined in the model terminology [RFC2911] section 12.2. The
following additional terms are introduced in this document: following additional terms are introduced in this document:
collection: an attribute syntax in which each attribute value is a collection: an attribute syntax in which each attribute value is a
set of attributes, called member attributes. set of attributes, called member attributes.
member attribute: an attribute that is defined to be used as one member attribute: an attribute that is defined to be used as one
of the attributes in a collection. of the attributes in a collection.
collection attribute: an attribute whose definition specifies the collection attribute: an attribute whose definition specifies the
'collection' attribute syntax and each of the member attributes 'collection' attribute syntax and each of the member attributes
that MAY occur in a collection attribute value. that MAY occur in a collection attribute value.
3 Definition of a Collection Attribute 3 Definition of a Collection Attribute
This section describes the requirements for any collection attribute This section describes the requirements for any collection attribute
definition. definition.
3.1 Information to Include 3.1 Information to Include
When a specification document defines an "xxx" collection attribute, When a specification document defines an "xxx" collection attribute,
i.e., an attribute whose attribute syntax type is 'collection' or i.e., an attribute whose attribute syntax type is 'collection' or
'1setOf collection'; the definition document MUST include the '1setOf collection'; the definition document MUST include the
following aspects of the attribute semantics. Suppose the "xxx" following aspects of the attribute semantics. Suppose the "xxx"
collection attribute contains N member attributes named "aaa1", collection attribute contains N member attributes named "aaa1",
"aaa2", _, "aaaN" ("aaaI" represents any one of these N member "aaa2", ..., "aaaN" ("aaaI" represents any one of these N member
attributes). attributes).
1. The name of the collection attribute MUST be specified (e.g. 1. The name of the collection attribute MUST be specified (e.g.,
"xxx"). The selection of the name "xxx" MUST follow the same rules "xxx"). The selection of the name "xxx" MUST follow the same
for uniqueness as for attributes of any other syntax type (as rules for uniqueness as for attributes of any other syntax type,
defined by IPP/1.1) unless "xxx" is a member attribute of another (as defined by IPP/1.1) unless "xxx" is a member attribute of
collection. Then the selection of the name "xxx" MUST follow the another collection. Then the selection of the name "xxx" MUST
rules for uniqueness defined in item 5a) of this list. follow the rules for uniqueness defined in item 5a) of this list.
2. The collection attribute syntax MUST be of type 'collection' or 2. The collection attribute syntax MUST be of type 'collection' or
'1setOf collection'. '1setOf collection'.
3. The context of the collection attribute MUST be specified, i.e., 3. The context of the collection attribute MUST be specified, i.e.,
whether the attribute is an operation attribute, a Job Template whether the attribute is an operation attribute, a Job Template
attribute, a Job Description attribute, a Printer Description attribute, a Job Description attribute, a Printer Description
attribute, a member attribute of a particular collection attribute, attribute, a member attribute of a particular collection
etc. attribute, etc.
4. An "xxx-supported" attribute MUST be specified and it has one of 4. An "xxx-supported" attribute MUST be specified and it has one of
the following two forms: the following two forms:
a)"xxx-supported" is a "1setOf collection" which enumerates all of a) "xxx-supported" is a "1setOf collection", which enumerates all
the supported collection values of "xxx". If a collection of of the supported collection values of "xxx". If a collection
this form contains a nested collection, it MUST be of the same of this form contains a nested collection, it MUST be of the
form. same form.
For example, "media-size-supported" might have the values {{x- For example, "media-size-supported" might have the values {{x-
dimension:210, y-dimension:297},{x-dimension:297, y- dimension:210, y-dimension:297},{x-dimension:297, y-
dimension:420}} to show that it supports two values of "media dimension:420}} to show that it supports two values of "media
size": A4 (210x297) and A3 (297x420). It does not support other size": A4 (210x297) and A3 (297x420). It does not support
combinations of "x-dimension" and "y-dimension" member other combinations of "x-dimension" and "y-dimension" member
attributes, such as 210x420 or 297x297 and it does not supported attributes, such as 210x420 or 297x297, and it does not support
non-enumerated values, such as 420x595. non-enumerated values, such as 420x595.
b)"xxx-supported" is a "1setOf type2 keyword" which enumerates b) "xxx-supported" is a "1setOf type2 keyword", which enumerates
the names of all of the member attributes of "xxx": "aaa1", the names of all of the member attributes of "xxx": "aaa1",
"aaa2", _, "aaaN". If a collection of this form contains a "aaa2", ..., "aaaN". If a collection of this form contains a
nested collection, it MAY be of either form. See item 5f) below nested collection, it MAY be of either form. See item 5f)
for details on supported values of member attributes. below for details on supported values of member attributes.
For example, "media-col-supported" might have the keyword For example, "media-col-supported" might have the keyword
values: "media-size" and "media-color". values: "media-size" and "media-color".
5. The member attributes MUST be defined. For each member attribute 5. The member attributes MUST be defined. For each member attribute,
the definition document MUST provide the following information: the definition document MUST provide the following information:
a)The member attribute's name (e.g., "aaa") MUST be unique within a) The member attribute's name (e.g., "aaa") MUST be unique within
the collection being defined and MUST either the collection being defined and MUST either:
i) reuse the attribute name of another attribute (that is unique i) reuse the attribute name of another attribute (that is
across the entire IPP attribute name space) and have the same unique across the entire IPP attribute name space) and
syntax and semantics as the reused attribute (if the condition have the same syntax and semantics as the reused attribute
of item 4b) above is met). For example, a member attribute (if the condition of item 4b) above is met). For example,
definition could reuse the IPP/1.1 "media" attribute. a member attribute definition could reuse the IPP/1.1
"media" attribute.
ii) potentially occur elsewhere in the entire IPP attribute ii) potentially occur elsewhere in the entire IPP attribute
name space. (if the condition of item 4a) above is met). For name space. (if the condition of item 4a) above is met).
example, a member attribute could be "x-dimension" which could For example, a member attribute could be "x-dimension",
potentially occur in another collection or as an attribute which could potentially occur in another collection or as
outside of a collection. an attribute outside of a collection.
iii) be unique across the entire IPP attribute name space (if iii) be unique across the entire IPP attribute name space (if
the condition of item 4b) above is met). For example, a member the condition of item 4b) above is met). For example, a
attribute could be "media-color" which must unique be across member attribute could be "media-color" which must be
the entire IPP attribute name space. unique across the entire IPP attribute name space.
b)Whether the member attribute is REQUIRED or OPTIONAL for the b) Whether the member attribute is REQUIRED or OPTIONAL for the
Printer to support Printer to support.
c)Whether the member attribute is REQUIRED or OPTIONAL for the c) Whether the member attribute is REQUIRED or OPTIONAL for the
client to supply in a request client to supply in a request.
d)The member attribute's syntax type, which can be any attribute d) The member attribute's syntax type, which can be any attribute
syntax, including '1setOf X', 'collection', and '1setOf syntax, including '1setOf X', 'collection', and '1setOf
collection'. If this attribute name reuses the name of another collection'. If this attribute name reuses the name of another
attribute (case of item a1 above), it MUST have the same attribute (case of item a1 above), it MUST have the same
attribute syntax, including cardinality (whether or not 1setOf). attribute syntax, including cardinality (whether or not
1setOf).
e)The semantics of the "aaa" member attribute. The semantic e) The semantics of the "aaa" member attribute. The semantic
definition MUST include a description of any constraint or definition MUST include a description of any constraint or
boundary conditions the member attribute places on the boundary conditions the member attribute places on the
associated attribute, especially if the attribute reuses the associated attribute, especially if the attribute reuses the
name of another attribute (case of item a1 above) name of another attribute (case of item a1 above).
f)The supported values for the each "aaaI" member attribute (of f) The supported values for each "aaaI" member attribute (of the
the member attributes "aaa1", "aaa2", _, "aaaN") is specified member attributes "aaa1", "aaa2", ..., "aaaN") is specified by
by one of two mechanisms. one of two mechanisms.
i) If "xxx-supported" is a "1setOf collection" (see item 4a) i) If "xxx-supported" is a "1setOf collection" (see item 4a)
above), the value for each "aaaI" is specified in each above), the value for each "aaaI" is specified in each
collection value of "xxx-supported" in the context of other collection value of "xxx-supported", in the context of
member attributes. That is, "xxx-supported" enumerates all other member attributes. That is, "xxx-supported"
supported values of "xxx". enumerates all supported values of "xxx".
ii) If the value of "xxx-supported" is a "1setOf type2 ii) If the value of "xxx-supported" is a "1setOf type2
keyword" (see item 4b) above), the supported values of "aaaI" keyword" (see item 4b) above), the supported values of
are the values specified by either i) the "aaaI-supported" "aaaI" are the values specified by either i) the "aaaI-
attribute or ii) the definition of the member attribute "aaaI" supported" attribute or ii) the definition of the member
within the document defining the "xxx" attribute. The values attribute "aaaI" within the document defining the "xxx"
of each member attribute "aaaI" are specified independently of attribute. The values of each member attribute "aaaI" are
other member attributes though a Printer is not required to specified independently of other member attributes, though
support all combinations of supported values. a Printer is not required to support all combinations of
supported values.
For example, "media-col-supported" might have the keyword For example, "media-col-supported" might have the keyword
values: "media-size" and "media-color". Using the first method values: "media-size" and "media-color". Using the first
for defining supported values (an "aaaI-supported" attribute), method for defining supported values (an "aaaI-supported"
the collection values of "media-col" are combinations of attribute), the collection values of "media-col" are
values of "media-size-supported" and "media-color- combinations of values of "media-size-supported" and
supported".If "media-size-supported" has the values of "media-color-supported". If "media-size-supported" has
'210x297' and '297x420' and "media-color-supported" has the the values of '210x297' and '297x420' and "media-color-
values of 'white' and 'pink', the Printer might support only supported" has the values of 'white' and 'pink', the
the combinations 'white-210x297', 'pink-210x297'and 'white- Printer might support only the combinations 'white-
297x420', and not 'pink-297x420'. 210x297', 'pink-210x297' and 'white-297x420', and not
'pink-297x420'.
If a collection contains a member "aaaI" whose syntax type is If a collection contains a member "aaaI", whose syntax
"text", the supported values would probably be defined by the type is "text", the supported values would probably be
definition of "xxx" rather than by the attribute "aaaI- defined by the definition of "xxx" rather than by the
supported". attribute "aaaI-supported".
g)the default value of each "aaaI" member attribute if it is g) the default value of each "aaaI" member attribute if it is
OPTIONAL for a client to supply the "aaa" member attribute in a OPTIONAL for a client to supply the "aaa" member attribute in a
request. The default value is specified by in the attribute's request. The default value is specified by the attribute's
definition within a document and MUST be one of the following: definition within a document and MUST be one of the following:
i) a fixed default i) a fixed default
ii) a mechanism by which the Printer determines default ii) a mechanism by which the Printer determines default
iii) an indefinite default that is left to the implementation. iii) an indefinite default that is left to the implementation.
iv) an attribute that the Printer uses to determine the default iv) an attribute that the Printer uses to determine the
default
6. The default value of "xxx" if a client does not supply it. The 6. The default value of "xxx", if a client does not supply it. The
default value is specified by in the attribute's definition within default value is specified by the attribute's definition within a
a document and MUST be one of the following: document and MUST be one of the following:
a)a fixed default a) a fixed default
b)a mechanism by which the Printer determines default b) a mechanism by which the Printer determines default
c)an indefinite default that is left to the implementation c) an indefinite default that is left to the implementation
d)a Printer attribute "xxx-default" which is a collection with the d) a Printer attribute "xxx-default" which is a collection with
same member attributes as "xxx". Though optional member the same member attributes as "xxx". If optional member
attributes may be absent in which case the Printer uses the attributes are absent, the Printer uses the defaulting rules of
defaulting rules of item 5g) above. item 5g) above.
7. The "xxx-ready (1setOf collection)" attribute if human intervention 7. The "xxx-ready (1setOf collection)" attribute, if human
is required to make many of the supported values available. For intervention is required to make many of the supported values
example, "media-col" is an attribute which has a "ready" attribute. available. For example, "media-col" is an attribute which has a
Most attributes do not have a "ready" attribute. "ready" attribute. Most attributes do not have a "ready"
attribute.
3.2 Nested Collections 3.2 Nested Collections
A member attribute may have a syntax type of 'collection' or '1setOf A member attribute may have a syntax type of 'collection' or '1setOf
collection', in which case it is called a nested collection collection', in which case it is called a nested collection
attribute. The rules for a nested collection attribute are the same attribute. The rules for a nested collection attribute are the same
as for a collection attribute as specified in section 3.1. as for a collection attribute as specified in section 3.1.
4 Collection Attributes as Attributes in Operations 4 Collection Attributes as Attributes in Operations
4.1 General Rules 4.1 General Rules
A collection value is like any other IPP/1.1 value, except that it is A collection value is like any other IPP/1.1 value, except that it is
structured. The rules for attributes with collection values are the structured. The rules for attributes with collection values are the
same as for attributes of any other syntax type (see IPP/1.1), be same as for attributes of any other syntax type (see IPP/1.1), be
they in any group of a request of a response. they in any group of a request of a response.
4.2 Unsupported Values 4.2 Unsupported Values
The rules for returning an unsupported collection attribute are an The rules for returning an unsupported collection attribute are an
extension to the current rules: extension to the current rules:
1. If the entire collection attribute is unsupported, then the 1. If the entire collection attribute is unsupported, then the
Printer returns just the collection attribute name with the Printer returns just the collection attribute name with the
'unsupported' out-of-band value (see the beginning of [RFC2911] 'unsupported' out-of-band value (see the beginning of [RFC2911]
section 4.1) in the Unsupported Attributes Group. section 4.1) in the Unsupported Attributes Group.
2. If a collection contains unrecognized, unsupported member 2. If a collection contains unrecognized, unsupported member
attributes and/or conflicting values, the attribute returned in attributes and/or conflicting values, the attribute returned in
the Unsupported Group is a collection containing the the Unsupported Group is a collection containing the unrecognized,
unrecognized, unsupported member attributes, and/or conflicting unsupported member attributes, and/or conflicting values. The
values. The unrecognized member attributes have an out-of-band unrecognized member attributes have an out-of-band value of
value of 'unsupported' (see the beginning of [RFC2911] section 'unsupported' (see the beginning of [RFC2911] section 4.1). The
4.1). The unsupported member attributes and conflicting values unsupported member attributes and conflicting values have their
have their unsupported or conflicting values. unsupported or conflicting values.
5 Example definition of a collection attribute 5 Example definition of a collection attribute
In some printing environments, it is desirable to allow the client to In some printing environments, it is desirable to allow the client to
select the media by its properties, e.g., weight, color, size, etc., select the media by its properties, e.g., weight, color, size, etc.,
instead of by name. In IPP/1.1 (see [RFC2911]), the "media (type3 instead of by name. In IPP/1.1 (see [RFC2911]), the "media (type3
keyword | name) Job Template attribute allows selection by name. It keyword | name) Job Template attribute allows selection by name. It
is tempting to extend the "media" attribute syntax to include is tempting to extend the "media" attribute syntax to include
"collection", but then existing clients could not understand default "collection", but then existing clients could not understand default
or supported media values that use the collection value. To preserve or supported media values that use the collection value. To preserve
interoperability, a new attribute MUST BE added, e.g., "media-col interoperability, a new attribute MUST BE added, e.g., "media-col
(collection)". The following subsections contain a sample definition (collection)". The following subsections contain a sample definition
of a simplified "media-col" attribute. The definition follows the of a simplified "media-col" attribute. The definition follows the
rules in section 3. rules in section 3.
All of the example attribute definitions in this document are All of the example attribute definitions in this document are
illustrative examples, rather than actual definitions. These illustrative examples, rather than actual definitions. These
examples are intended to illustrate how to define collection examples are intended to illustrate how to define collection
attributes. Other documents MUST define collection attributes for attributes. Other documents MUST define collection attributes for
use in actual interchange. Such definitions may be very similar to use in actual interchange. Such definitions may be very similar to
the examples in this document, since we attempted to pick useful the examples in this document, since we attempted to pick useful
examples. examples.
Note: we picked the name "media-col" because the name "media" is Note: we picked the name "media-col" because the name "media" is
already in use. Ordinarily the collection attribute would have a name already in use. Ordinarily the collection attribute would have a
like any other attribute and would not end in "col". name like any other attribute and would not end in "col".
The member attributes of "media-col" attribute ("media-color (type 3 The member attributes of "media-col" attribute ("media-color (type 3
keyword)" and "media-size (collection)") both follow the naming rules keyword)" and "media-size (collection)") both follow the naming rules
of item 4a3 of section 3, i.e. the names are unique across the entire of item 4a3 of section 3, i.e., the names are unique across the
IPP attribute name space. The member attributes of the "media-size entire IPP attribute name space. The member attributes of the
(collection)" member attribute ("x-dimension (integer(0,MAX))" and "media-size (collection)" member attribute ("x-dimension
"y-dimension (integer(0,MAX))") both follow the naming rules of item (integer(0:MAX))" and "y-dimension (integer(0:MAX))") both follow the
4a2 of section 3, i.e. they potentially occur elsewhere in the IPP naming rules of item 4a2 of section 3, i.e., they potentially occur
attribute name space. elsewhere in the IPP attribute name space.
5.1 media-col (collection) 5.1 media-col (collection)
The "media-col" (collection) attribute augments the IPP/1.1 [RFC2911] The "media-col" (collection) attribute augments the IPP/1.1 [RFC2911]
"media" attribute. This collection attribute enables a client end "media" attribute. This collection attribute enables a client end
user to submit a list of media characteristics to the Printer. When user to submit a list of media characteristics to the Printer. When
the client specifies media using the "media-col" collection the client specifies media using the "media-col" collection
attribute, the Printer object MUST match the requested media exactly. attribute, the Printer object MUST match the requested media exactly.
The 'collection' consists of the following member attributes: The 'collection' consists of the following member attributes:
Table 1 - "media-col" member attributes Table 1 - "media-col" member attributes
Attribute name attribute syntax reque Printer Attribute name attribute syntax request Printer
st Support Support
media-color type3 keyword | name (MAX) MAY MUST media-color type3 keyword | name (MAX) MAY MUST
media-size collection MUST MUST media-size collection MUST MUST
The definitions for the member attributes is given in the following The definitions for the member attributes is given in the following
sub-sections: sub-sections:
5.1.1 media-color (type3 keyword | name(MAX) 5.1.1 media-color (type3 keyword | name(MAX)
This member attribute identifies the color of the media. Valid This member attribute identifies the color of the media. Valid
values are 'red', 'white' and 'blue' values are 'red', 'white' and 'blue'.
The "media-color-supported" (1setOf (type3 keyword | name(MAX))) The "media-color-supported" (1setOf (type3 keyword | name(MAX)))
Printer attribute identifies the values of this "media-color" Printer attribute identifies the values of this "media-color" member
member attribute that the Printer supports, i.e., the colors attribute that the Printer supports, i.e., the colors supported.
supported.
If the client omits this member attribute, the Printer determines If the client omits this member attribute, the Printer determines the
the value in an implementation dependent manner. value in an implementation dependent manner.
5.1.2 media-size (collection) 5.1.2 media-size (collection)
This member attribute identifies the size of the media. The This member attribute identifies the size of the media. The
'collection' consists of the member attributes shown in Table 2: 'collection' consists of the member attributes shown in Table 2:
Table 2 - "media-size" collection member attributes Table 2 - "media-size" collection member attributes
Attribute attribute syntax request Printer Attribute name attribute syntax request Printer
name Support Support
x-dimension integer (0:MAX) MUST MUST x-dimension integer (0:MAX) MUST MUST
y-dimension integer (0:MAX) MUST MUST y-dimension integer (0:MAX) MUST MUST
The definitions for the member attributes is given in the
following sub-sections:
5.1.2.1 x-dimension (integer(0:MAX)) The definitions for the member attributes are given in the following
This attribute identifies the width of the media in inch units sub-sections:
along the X axis.
5.1.2.2 y-dimension (integer(0:MAX)) 5.1.2.1 x-dimension (integer(0:MAX))
This attribute identifies the height of the media in inch
units along the Y axis.
The "media-size-supported" (1setOf collection) Printer This attribute identifies the width of the media in inch units along
attribute identifies the values of this "media-size" member the X axis.
attribute that the Printer supports, i.e., the size
combinations supported. The names of the member attributes 5.1.2.2 y-dimension (integer(0:MAX))
are the same as the member attributes of the "media-size"
collection attribute, namely "x-dimension", and "y-dimension", This attribute identifies the height of the media in inch units along
since they have the same attribute syntax and the same the Y axis.
semantics.
The "media-size-supported" (1setOf collection) Printer attribute
identifies the values of this "media-size" member attribute that the
Printer supports, i.e., the size combinations supported. The names
of the member attributes are the same as the member attributes of the
"media-size" collection attribute, namely "x-dimension", and "y-
dimension", since they have the same attribute syntax and the same
semantics.
5.2 media-col-default (collection) 5.2 media-col-default (collection)
The "media-col-default" Printer attribute specifies the media that The "media-col-default" Printer attribute specifies the media that
the Printer uses, if any, if the client omits the "media-col" and the Printer uses, if any, if the client omits the "media-col" and
"media". Job Template attribute in the Job Creation operation (and "media". Job Template attributes in the Job Creation operation and
the PDL doesn't include a media specification). The member the PDL do not include a media specification. The member attributes
attributes are defined in Table 1. A Printer MUST support the same are defined in Table 1. A Printer MUST support the same member
member attributes for this default collection attribute as it attributes for this default collection attribute as it supports for
supports for the corresponding "media-col" Job Template attribute. the corresponding "media-col" Job Template attribute.
5.3 media-col-ready (1setOf collection) 5.3 media-col-ready (1setOf collection)
The "media-col-ready" Printer attribute identifies the media that are The "media-col-ready" Printer attribute identifies the media that are
available for use without human intervention, i.e., the media that available for use without human intervention, i.e., the media that
are ready to be used without human intervention. The collection are ready to be used without human intervention. The collection
value MUST have all of the member attributes that are supported in value MUST have all of the member attributes that are supported in
Table 1. Table 1.
5.4 media-col-supported (1setOf type2 keyword) 5.4 media-col-supported (1setOf type2 keyword)
The "media-col-supported" Printer attribute identifies the keyword The "media-col-supported" Printer attribute identifies the keyword
names of the member attributes supported in the "media-col" names of the member attributes supported in the "media-col"
collection Job Template attribute, i.e., the keyword names of the collection Job Template attribute, i.e., the keyword names of the
member attributes in Table 1 that the Printer supports. member attributes in Table 1 that the Printer supports.
6 A Second Example Definition Of A Collection Attribute 6 A Second Example Definition Of A Collection Attribute
All of the example attribute definitions in this document are All of the example attribute definitions in this document are
illustrative examples, rather than actual definitions. These illustrative examples, rather than actual definitions. These
examples are intended to illustrate how to define collection examples are intended to illustrate how to define collection
attributes. Other documents MUST define collection attributes for attributes. Other documents MUST define collection attributes for
use in actual interchange. Such definitions may be very similar to use in actual interchange. Such definitions may be very similar to
the examples in this document, since we attempted to pick useful the examples in this document, since we attempted to pick useful
examples. examples.
In some printing environments, it is desirable to allow the client to In some printing environments, it is desirable to allow the client to
select the media for the job start sheet. The reason for not adding select the media for the job start sheet. The reason for not adding
the 'collection' attribute syntax to the existing "job-sheets" Job the 'collection' attribute syntax to the existing "job-sheets" Job
Template attribute is the same as for "media". Instead, a new Job Template attribute is the same as for "media". Instead, a new Job
Template attribute is introduced, e.g. "job-sheet-col (collection)". Template attribute is introduced, e.g., "job-sheet-col (collection)".
The member attributes of "job-sheet-col" attribute ("job-sheets The member attributes of "job-sheet-col" attribute ("job-sheets (type
(type 3 keyword)" and "media (type3 keyword | name)") both follow 3 keyword)" and "media (type3 keyword | name)") both follow the
the naming rules of item 4a1 of section 3, i.e they reuse existing naming rules of item 4a1 of section 3, i.e., they reuse existing IPP
IPP attributes. According to the rules, their supported values come attributes. According to the rules, their supported values come from
from the existing IPP attributes: "job-sheets-supported" and "media- the existing IPP attributes: "job-sheets-supported" and "media-
supported". However, their default values do not come from "job- supported". However, their default values do not come from "job-
sheets-default" and "media-default", respectively. Rather the sheets-default" and "media-default", respectively. Rather, the
definition of "job-sheet-col" says that "job-sheets (type 3 keyword)" definition of "job-sheet-col" says that "job-sheets (type 3 keyword)"
is required and if "media (type3 keyword | name)" is absent, the is required and if "media (type3 keyword | name)" is absent, the
Printer uses the same media as the rest of the job uses. Printer uses the same media as the rest of the job uses.
If "job-sheet-col" attribute were defined to contain the member If "job-sheet-col" attribute was defined to contain the member
attribute "job-sheet-media (type3 keyword | name)" instead of "media attribute "job-sheet-media (type3 keyword | name)" instead of "media
(type3 keyword | name)", then the definition would also have to (type3 keyword | name)", then the definition would also have to
specify a "job-sheet-media-supported (1setOf (type3 keyword | specify a "job-sheet-media-supported (1setOf (type3 keyword | name))"
name))" whose values would be independent of "media-supported whose values would be independent of "media-supported (1setOf (type3
(1setOf (type3 keyword | name))" and would be set separately by a keyword | name))" and would be set separately by a System
System Administrator. Administrator.
The actual text for the definition of the attribute is left as an The actual text for the definition of the attribute is left as an
exercise for the reader. exercise for the reader.
7 Encoding 7 Encoding
This section defines the additional encoding tags used according to This section defines the additional encoding tags used according to
[RFC2910] and gives an example of their use. The encoding tags [RFC2910] and gives an example of their use. The encoding tags
define in this document MUST be used by all collection attributes defined in this document MUST be used by all collection attributes
defined in other documents. However, the example of their use is defined in other documents. However, the example of their use is
illustrative only. illustrative only.
7.1 Additional tags defined for representing a collection attribute 7.1 Additional tags defined for representing a collection attribute
value value
The 'collection' attribute syntax uses the tags defined in Table 3. The 'collection' attribute syntax uses the tags defined in Table 3.
Table 3 - Tags defined for encoding the 'collection' attribute syntax Table 3 - Tags defined for encoding the 'collection' attribute syntax
Tag name Tag Meaning Tag name Tag
value value Meaning
begCollection 0x34 Begin the collection attribute value. begCollection 0x34 Begin the collection attribute value.
endCollection 0x37 End the collection attribute value. endCollection 0x37 End the collection attribute value.
memberAttrName 0x4A The value is the name of the memberAttrName 0x4A The value is the name of the
collection member attribute collection member attribute
When encoding a collection attribute "xxx" that contains an attribute When encoding a collection attribute "xxx" that contains an attribute
"aaa" and is not inside another collection, the encoding follows "aaa" and is not inside another collection, the encoding follows
these rules: these rules:
1. The beginning of the collection is indicated with a value tag 1. The beginning of the collection is indicated with a value tag that
that MUST be syntax type 'begCollection' (0x34) with a name MUST be syntax type 'begCollection' (0x34) with a name length and
length and Name field that represent the name of the collection Name field that represent the name of the collection attribute
attribute ("xxx") as with any attribute, followed by a value. The ("xxx") as with any attribute, followed by a value. The Printer
Printer MAY ignore the value and its length of MAY be 0. In the MAY ignore the value and its length MAY be 0. In the future,
future, however, this field MAY contain useful information, such however, this field MAY contain useful information, such as the
as the collection name (cf. the name of a C struct). collection name (cf. the name of a C struct).
2. Each member attribute is encoded as a sequence of two or more 2. Each member attribute is encoded as a sequence of two or more
values that appear to be part of a single multi-valued attribute, values that appear to be part of a single multi-valued attribute,
i.e. 1setOf. The first value after the 'begCollection' value has i.e., 1setOf. The first value after the 'begCollection' value has
the attribute syntax 'memberAttrName' (0x4A) and its value holds the attribute syntax, 'memberAttrName' (0x4A), and its value holds
the name of the first member attribute (e.g. "aaa"). The second the name of the first member attribute (e.g., "aaa"). The second
value holds the first member's attribute value, which can be of value holds the first member's attribute value, which can be of
any attribute syntax, except 'memberAttrName' or 'endCollection'. any attribute syntax, except 'memberAttrName' or 'endCollection'.
If the first member's attribute value is multi-valued, the third If the first member's attribute value is multi-valued, the third
value holds the second value of the first member's value. value holds the second value of the first member's value.
Otherwise, the third value holds the name of second member Otherwise, the third value holds the name of second member
attribute (e.g. "bbb") and its attribute syntax is attribute (e.g., "bbb"), and its attribute syntax is
'memberAttrName'. In this case, the fourth member's value is the 'memberAttrName'. In this case, the fourth member's value is the
value of "bbb". value of "bbb".
Note that the technique of encoding a 'collection' as a '1setOf' Note that the technique of encoding a 'collection' as a '1setOf'
makes it easy for a Printer that doesn't support a particular makes it easy for a Printer that doesn't support a particular
collection attribute (or the collection attribute syntax at all) collection attribute (or the collection attribute syntax at all)
to simply skip over the entire collection value. to simply skip over the entire collection value.
3. The end of the collection is indicated with a value tag that MUST 3. The end of the collection is indicated with a value tag that MUST
be syntax type 'endCollection' (e.g. 0x37) and MAY have a zero be syntax type 'endCollection' (e.g., 0x37) and MAY have a zero
name length and a zero value length. In the future, this field name length and a zero value length. In the future, this field
MAY contain useful information,such as the collection name that MAY contain useful information, such as the collection name that
matches the one in the 'begCollection' . matches the one in the 'begCollection' .
4. It is valid to have a member attribute that is, itself, a 4. It is valid to have a member attribute that is itself, a
collection attribute, i.e., collections can be nested within collection attribute, i.e., collections can be nested within
collections. This is represented by the occurrence of a member collections. This is represented by the occurrence of a member
attribute that is of attribute syntax type 'begCollection'. Such attribute that is of attribute syntax type 'begCollection'. Such
a collection is terminated by a matching 'endCollection'. The a collection is terminated by a matching 'endCollection'. The
name of such a member attribute is in the immediately preceding name of such a member attribute is in the immediately preceding
value whose syntax type is 'memberAttrName'. value, whose syntax type is 'memberAttrName'.
5. It is valid for a collection attribute to be multi-valued, i.e., 5. It is valid for a collection attribute to be multi-valued, i.e.,
have more than one collection value. If the next attribute have more than one collection value. If the next attribute
immediately following the 'endCollection' has a zero name length immediately following the 'endCollection' has a zero name length
and a tag of 'begCollection', then the collection attribute is a and a tag of 'begCollection', then the collection attribute is a
multi-valued collection, as with any attribute. This statement multi-valued collection, as with any attribute. This statement
applies to collections within collections and collections that applies to collections within collections and collections that are
are not in collections. not in collections.
7.2 Example encoding: "media-col" (collection) 7.2 Example encoding: "media-col" (collection)
The collection specified in section 5 is used for the encoding The collection specified in section 5 is used for the encoding
example shown in Table 5. The example also shows nested collections, example shown in Table 5. The example also shows nested collections,
since the "media-size" member attribute is a 'collection. The since the "media-size" member attribute is a 'collection. The
encoding example represents a blue 4x6-index cards and takes 216 encoding example represents a blue 4x6-index card and takes 216
octets. The Appendices contains more complex examples. octets. The Appendices contain more complex examples.
Additional examples have been included in the appendices. Additional examples have been included in the appendices.
The overall structure of the two collection values can be pictorially The overall structure of the two collection values can be pictorially
represented as: represented as:
"media-col" = "media-col" =
{ "media-color" = 'blue'; { "media-color" = 'blue';
"media-size" = "media-size" =
{ "x-dimension" = 6; { "x-dimension" = 6;
"y-dimension" = 4 "y-dimension" = 4
} }
}, },
The full encoding is in table 4. A simplified view of the encoding The full encoding is in table 5. A simplified view of the encoding
looks like this: looks like this:
Table 4 - Overview Encoding of "media-col" collection Table 4 - Overview Encoding of "media-col" collection
Tag Value Name Value Tag Value Name Value
begCollection media-col ""
memberAttrName "" media-color begCollection media-col ""
keyword "" blue memberAttrName "" media-color
memberAttrName "" media-size keyword "" blue
begCollection "" "" memberAttrName "" media-size
memberAttrName "" x-dimension begCollection "" ""
integer "" 6 memberAttrName "" x-dimension
memberAttrName "" y-dimension integer "" 6
integer "" 4 memberAttrName "" y-dimension
endCollection "" "" integer "" 4
endCollection "" "" endCollection "" ""
endCollection "" ""
Table 5 - Example Encoding of "media-col" collection Table 5 - Example Encoding of "media-col" collection
Octets Symbolic Value Protocol comments Octets Symbolic Value Protocol comments
field field
0x34 begCollection value-tag beginning of the "media- 0x34 begCollection value-tag beginning of the "media-
col" collection attribute col" collection attribute
0x0009 name- length of (collection) 0x0009 name- length of (collection)
length attribute name length attribute name
Octets Symbolic Value Protocol comments media-col media-col name name of (collection)
field attribute
media-col media-col name name of (collection) 0x0000 value- defined to be 0 for this
attribute length type
0x0000 value- defined to be 0 for this no value (since value-
length type length was 0)
no value (since value- 0x4A memberAttrName value-tag starts a new member
length was 0) attribute: "media-color"
0x4A memberAttrName value-tag starts a new member 0x0000 name- defined to be 0 for this
attribute: "media-color" length type, so part of 1setOf
0x0000 name- defined to be 0 for this no name (since name-length
length type, so part of 1setOf was 0)
no name (since name-length 0x000B value- length of "media-color"
was 0) length keyword
0x000B value- length of "media-color" media-color media-color value value is name of 1st
length keyword member attribute
media-color media-color value value is name of 1st 0x44 keyword type value-tag keyword type
member attribute
0x44 keyword type value-tag keyword type 0x0000 name- 0 indicates 1setOf
length
0x0000 name- 0 indicates 1setOf no name (since name-length
length was 0)
no name (since name-length Octets Symbolic Value Protocol comments
was 0) field
0x0004 value- 0x0004 value-
length length
blue blue value value of 1st member blue blue value value of 1st member
attribute attribute
0x4A memberAttrName value-tag starts a new member 0x4A memberAttrName value-tag starts a new member
attribute: "media-size" attribute: "media-size"
Octets Symbolic Value Protocol comments 0x0000 name- defined to be 0 for this
field length type, so part of 1setOf
0x0000 name- defined to be 0 for this no name (since name-length
length type, so part of 1setOf was 0)
no name (since name-length 0x000A value- length of "media-size"
was 0) length keyword
0x000A value- length of "media-size" media-size media-size value Name of 2nd member
length keyword attribute
media-size media-size value Name of 2nd member 0x34 begCollection value-tag Beginning of the "media-
attribute size" collection attribute
which is a sub-collection
0x34 begCollection value-tag Beginning of the "media- 0x0000 name- 0 indicates 1setOf
size" collection attribute length
which is a sub-collection
0x0000 name- 0 indicates 1setOf no name (since name-length
length was 0)
no name (since name-length 0x0000 value- collection attribute names
was 0) length have no value
0x0000 value- collection attribute names no value (since value-
length have no value length was 0)
no value (since value- 0x4A memberAttrName value-tag starts a new member
length was 0) attribute: "x-dimension"
0x4A memberAttrName value-tag starts a new member Octets Symbolic Value Protocol comments
attribute: "x-dimension" field
0x0000 name- defined to be 0 for this 0x0000 name- defined to be 0 for this
length type, so part of 1setOf length type, so part of 1setOf
no name (since name-length no name (since name-length
was 0) was 0)
0x000B value- length of "x-dimension" 0x000B value- length of "x-dimension"
length keyword length keyword
Octets Symbolic Value Protocol comments x-dimension x-dimension value name of 1st sub-
field collection member
attribute
x-dimension x-dimension value name of 1st sub- 0x21 integer type value-tag attribute type
collection member
attribute
0x21 integer type value-tag attribute type 0x0000 name- 0 indicates 1setOf
length
0x0000 name- 0 indicates 1setOf no name (since name-length
length was 0)
no name (since name-length 0x0004 value- length of an integer = 4
was 0) length
0x0004 value- length of an integer = 4 0x0006 value value of 1st sub-
length collection member
attribute
0x0006 value value of 1st sub- 0x4A memberAttrName value-tag starts a new member
collection member attribute: "y-dimension"
attribute
0x4A memberAttrName value-tag starts a new member 0x0000 name- defined to be 0 for this
attribute: "y-dimension" length type, so part of 1setOf
0x0000 name- defined to be 0 for this no name (since name-length
length type, so part of 1setOf was 0)
no name (since name-length 0x000B value- length of the "y-
was 0) length dimension" keyword
0x000B value- length of the "y- Octets Symbolic Value Protocol comments
length dimension" keyword field
y-dimension y-dimension value name of 2nd sub- y-dimension y-dimension value name of 2nd sub-
collection member collection member
attribute attribute
0x21 integer type value-tag attribute type 0x21 integer type value-tag attribute type
0x0000 name- 0 indicates 1setOf 0x0000 name- 0 indicates 1setOf
length length
Octets Symbolic Value Protocol comments no name (since name-length
field was 0)
no name (since name-length 0x0004 value- length of an integer = 4
was 0) length
0x0004 value- length of an integer = 4 0x0004 value value of 2nd sub-
length collection member
attribute
0x0004 value value of 2nd sub- 0x37 endCollection value-tag end of the sub-collection
collection member
attribute
0x37 endCollection value-tag end of the sub-collection 0x0000 name- defined to be 0 for this
length type, so part of 1setOf
0x0000 name- defined to be 0 for this no name (since name-length
length type, so part of 1setOf was 0)
no name (since name-length 0x0000 value- defined to be 0 for this
was 0) length type
0x0000 value- defined to be 0 for this no value (since value-
length type length was 0)
no value (since value- 0x37 endCollection value-tag end of the 1st collection
length was 0) value in 1setOf
0x37 endCollection value-tag end of the 1st collection 0x0000 name- defined to be 0 for this
value in 1setOf length type, so part of 1setOf
0x0000 name- defined to be 0 for this Octets Symbolic Value Protocol comments
length type, so part of 1setOf field
no name (since name-length no name (since name-length
was 0) was 0)
0x0000 value- defined to be 0 for this 0x0000 value- defined to be 0 for this
length type length type
no value (since value- no value (since value-
length was 0) length was 0)
8 Legacy issues 8 Legacy issues
IPP 1.x Printers and Clients will gracefully ignore collections and IPP 1.x Printers and Clients will gracefully ignore collections and
its member attributes if it does not understand the collection. The its member attributes if it does not understand the collection. The
begCollection and endCollection elements each look like an attribute begCollection and endCollection elements each look like an attribute
with an attribute syntax that the recipient doesn't support and so with an attribute syntax that the recipient doesn't support and so
should ignore the entire attribute. The individual member attributes should ignore the entire attribute. The individual member attributes
and their values will look like a 1setOf values of the collection and their values will look like a 1setOf values of the collection
attribute, so that the Printer simply ignores the entire attribute attribute, so that the Printer simply ignores the entire attribute
and all of its values. Returning unsupported attributes is also and all of its values. Returning unsupported attributes is also
simple, since only the name of the collection attribute is returned simple, since only the name of the collection attribute is returned
with the 'unsupported' out-of-band value (see section 4.2). with the 'unsupported' out-of-band value (see section 4.2).
9 IANA Considerations 9 IANA Considerations
This section contains the exact information for IANA to add to the
IPP Registries according to the procedures defined in "IPP/1.1 Model
and Semantics" document [RFC2911] section 6.
Note to RFC Editors: Replace RFC NNNN below with the RFC number for
this document, so that it accurately reflects the content of the
information for the IANA Registry.
9.1 Attribute Syntax Registration
The attribute syntax defined in this document will be published by
IANA according to the procedures in RFC 2911 [RFC2911] section 6.3
with the following path:
ftp.isi.edu/iana/assignments/ipp/attribute-syntaxes/
The registry entry will contain the following information: The following table provides registration for the 'collection'
attribute syntax defined in this document. This is to be registered
according to the procedures in RFC 2911 [RFC2911] section 6.3.
Reference: Tag value: Attribute Syntaxes: Ref. Section:
RFC NNNN [this document] collection RFC 3382 3
0x34 begCollection RFC 3382 7.1
0x37 endCollection RFC 3382 7.1
0x4A memberAttrName RFC 3382 7.1
Attribute Syntaxes: Ref. Section: The resulting attribute syntax registration will be published in the
collection RFC NNNN 3 http://www.iana.org/assignments/ipp-registrations registry.
10 Internationalization Considerations 10 Internationalization Considerations
This attribute syntax by itself has no impact on This attribute syntax by itself has no impact on
internationalization. However, the member attributes that are internationalization. However, the member attributes that are
subsequently defined for use in a collection may have subsequently defined for use in a collection may have
internationalization considerations, as may any attribute, according internationalization considerations, as may any attribute, according
to [RFC2911]. to [RFC2911].
11 Security Considerations 11 Security Considerations
This attribute syntax causes no more security concerns than any other This attribute syntax causes no more security concerns than any other
attribute syntax. It is only the attributes that are subsequently attribute syntax. It is only the attributes that are subsequently
defined to use this or any other attribute syntax that may have defined, to use this or any other attribute syntax, that may have
security concerns, depending on the semantics of the attribute, security concerns, depending on the semantics of the attribute,
according to [RFC2911]. according to [RFC2911].
12 References 12 References
[ipp-ntfy] 12.1 Normative References
Isaacson, S., Martin, J., deBry, R., Hastings, T., Shepherd, M.,
Bergman, R. " Internet Printing Protocol/1.0 & 1.1: IPP Event
Notification Specification" draft-ietf-ipp-not-spec-02.txt, work in
progress, February 2, 2000.
[RFC2565]
Herriot, R., Butler, S., Moore, P., Tuner, R., "Internet Printing
Protocol/1.0: Encoding and Transport", RFC 2565, April 1999.
[RFC2566]
R. deBry, T. Hastings, R. Herriot, S. Isaacson, P. Powell,
"Internet Printing Protocol/1.0: Model and Semantics", RFC 2566,
April 1999.
[RFC2567]
Wright, D., "Design Goals for an Internet Printing Protocol", RFC
2567, April 1999.
[RFC2568]
Zilles, S., "Rationale for the Structure and Model and Protocol for
the Internet Printing Protocol", RFC 2568, April 1999.
[RFC2569] [RFC2910] Herriot, R., Butler, S., Moore, P. and R. Turner, "Internet
Herriot, R., Hastings, T., Jacobs, N., Martin, J., "Mapping between Printing Protocol/1.1: Encoding and Transport", RFC 2910,
LPD and IPP Protocols", RFC 2569, April 1999. September 2000.
[RFC2616] [RFC2911] Isaacson, S., deBry, R., Hastings, T., Herriot, R. and P.
R. Fielding, J. Gettys, J. Mogul, H. Frystyk, L. Masinter, P. Powell, "Internet Printing Protocol/1.1: Model and
Leach, T. Berners-Lee, "Hypertext Transfer Protocol - HTTP/1.1", Semantics", RFC 2911, September 2000.
RFC 2616, June 1999.
[RFC2910] 12.2 Informative References
Herriot, R., Butler, S., Moore, P., Turner, R., "Internet Printing
Protocol/1.1: Encoding and Transport", draft-ietf-ipp-protocol-v11-
05.txt, March 1, 2000.
[RFC2911] [RFC2565] Herriot, R., Butler, S., Moore, P. and R. Tuner, "Internet
Isaacson, S., deBry, R., Hastings, T., Herriot, R., Powell, P., Printing Protocol/1.0: Encoding and Transport", RFC 2565,
"Internet Printing Protocol/1.1: Model and Semantics", RFC 2911, April 1999.
September 2000.
13 Author's Addresses [RFC2566] deBry, R., Hastings, T., Herriot, R., Isaacson, S. and P.
Powell, "Internet Printing Protocol/1.0: Model and
Semantics", RFC 2566, April 1999.
Roger deBry [RFC2567] Wright, D., "Design Goals for an Internet Printing
Utah Valley State College Protocol", RFC 2567, April 1999.
Orem, UT 84058
Phone: (801) 222-8000
EMail: debryro@uvsc.edu
Tom Hastings [RFC2568] Zilles, S., "Rationale for the Structure and Model and
Xerox Corporation Protocol for the Internet Printing Protocol", RFC 2568,
737 Hawaii St. ESAE 231 April 1999.
El Segundo, CA 90245
Phone: 310-333-6413
Fax: 310-333-5514
e-mail: hastings@cp10.es.xerox.com
Robert Herriot [RFC2569] Herriot, R., Hastings, T., Jacobs, N. and J. Martin,
Xerox Corp. "Mapping between LPD and IPP Protocols", RFC 2569, April
3400 Hill View Ave, Building 1 1999.
Palo Alto, CA 94304
Phone: 650-813-7696
Fax: 650-813-6860
e-mail: robert.herriot@pahv.xerox.com
Kirk Ocke [RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H., Masinter,
Xerox Corp. L., Leach, P. and T. Berners-Lee, "Hypertext Transfer
800 Phillips Rd Protocol - HTTP/1.1", RFC 2616, June 1999.
M/S 139-05A
Webster, NY 14580
Phone: (716) 442-4832
EMail: kirk.ocke@usa.xerox.com
Peter Zehler [RFC3196] Hastings, T., Manros, C., Zehler, P., Kugler, C. and H.
Xerox Corp. Holst, "Internet Printing Protocol/1.1: Implementor's
800 Phillips Rd Guide", RFC 3196, November 2001.
M/S 139-05A
Webster, NY 14580
Phone: (716) 265-8755
EMail: peter.zehler@usa.xerox.com
14 Appendix A: Encoding Example of a Simple Collection Appendix A: Encoding Example of a Simple Collection (Informative)
The overall structure of the collection value can be pictorially The overall structure of the collection value can be pictorially
represented as: represented as:
" media-size " = "media-size" =
{ "x-dimension" = 6; { "x-dimension" = 6;
"y-dimension" = 4 "y-dimension" = 4
} }
A simplified view of the encoding would look like this: A simplified view of the encoding would look like this:
Table 6 - Overview Encoding of simple collection Table 6 - Overview Encoding of simple collection
Tag Value Name Value Tag Value Name Value
begCollection media-size "" begCollection media-size ""
memberAttrName "" x-dimension memberAttrName "" x-dimension
integer "" 6 integer "" 6
memberAttrName "" y-dimension memberAttrName "" y-dimension
integer "" 4 integer "" 4
endCollection "" "" endCollection "" ""
Note: "" represents a name or value whose length is 0. Note: "" represents a name or value whose length is 0.
Table 7 - Example Encoding of simple collection Table 7 - Example Encoding of simple collection
Octets Symbolic Value Protocol comments Octets Symbolic Value Protocol comments
field field
0x34 begCollection value-tag beginning of the "media-
size" collection attribute
Octets Symbolic Value Protocol comments 0x34 begCollection value-tag beginning of the "media-
field size" collection attribute
0x000A name- length of (collection) 0x000A name- length of (collection)
length attribute name length attribute name
media-size media-size name name of (collection) media-size media-size name name of (collection)
attribute attribute
0x0000 value- defined to be 0 for this Octets Symbolic Value Protocol comments
length type field
no value (since value- 0x0000 value- defined to be 0 for this
length was 0) length type
0x4A memberAttrName value-tag starts member attribute: no value (since value-
"x-dimension" length was 0)
0x0000 name- defined to be 0 for this 0x4A memberAttrName value-tag starts member attribute:
length type, so part of 1setOf "x-dimension"
no name (since name-length 0x0000 name- defined to be 0 for this
was 0) length type, so part of 1setOf
0x000B value- length of "x-dimension" no name (since name-length
length keyword was 0)
x-dimension x-dimension value name of 1st collection 0x000B value- length of "x-dimension"
member attribute length keyword
0x21 integer type value-tag attribute type x-dimension x-dimension value name of 1st collection
member attribute
0x0000 name- 0 indicates 1setOf 0x21 integer type value-tag attribute type
length
no name (since name-length 0x0000 name- 0 indicates 1setOf
was 0) length
0x0004 value- length of an integer = 4 no name (since name-length
length was 0)
0x0006 value value of 1st collection 0x0004 value- length of an integer = 4
member attribute length
Octets Symbolic Value Protocol comments 0x0006 value value of 1st collection
field member attribute
0x4A memberAttrName value-tag starts a new member 0x4A memberAttrName value-tag starts a new member
attribute: "y-dimension" attribute: "y-dimension"
0x0000 name- defined to be 0 for this 0x0000 name- defined to be 0 for this
length type, so part of 1setOf length type, so part of 1setOf
no name (since name-length no name (since name-length
was 0) was 0)
0x000B value- length of the "y- Octets Symbolic Value Protocol comments
length dimension" keyword field
y-dimension y-dimension value name of 2nd collection 0x000B value- length of the "y-
member attribute length dimension" keyword
0x21 integer type value-tag attribute type y-dimension y-dimension value name of 2nd collection
member attribute
0x0000 name- 0 indicates 1setOf for 0x21 integer type value-tag attribute type
length media-size
no name (since name-length 0x0000 name- 0 indicates 1setOf for
was 0) length media-size
0x0004 value- length of an integer = 4 no name (since name-length
length was 0)
0x0004 value value of 2nd collection 0x0004 value- length of an integer = 4
member attribute length
0x37 endCollection value-tag end of the collection 0x0004 value value of 2nd collection
member attribute
0x0000 name- defined to be 0 for this 0x37 endCollection value-tag end of the collection
length type, so part of 1setOf
no name (since name-length 0x0000 name- defined to be 0 for this
was 0) length type, so part of 1setOf
0x0000 value- defined to be 0 for this no name (since name-length
length type was 0)
Octets Symbolic Value Protocol comments 0x0000 value- defined to be 0 for this
field length type
no value (since value- no value (since value-
length was 0) length was 0)
15 Appendix B: Encoding Example of 1setOf Collection Appendix B: Encoding Example of 1setOf Collection (Informative)
The overall structure of the collection value can be pictorially The overall structure of the collection value can be pictorially
represented as: represented as:
"media-size-supported" = "media-size-supported" =
{ "x-dimension" = 6; { "x-dimension" = 6;
"y-dimension" = 4 "y-dimension" = 4
}, },
{ "x-dimension" = 3; { "x-dimension" = 3;
"y-dimension" = 5 "y-dimension" = 5
}; };
A simplified view of the encoding would look like this: A simplified view of the encoding would look like this:
Table 8 - Overview Encoding of 1setOf collection Table 8 - Overview Encoding of 1setOf collection
Tag Value Name Value Tag Value Name Value
begCollection media-size- "" begCollection media-size- ""
supported supported
memberAttrName "" x-dimension memberAttrName "" x-dimension
integer "" 6 integer "" 6
memberAttrName "" y-dimension memberAttrName "" y-dimension
integer "" 4 integer "" 4
endCollection "" "" endCollection "" ""
begCollection "" ""
memberAttrName "" x-dimension begCollection "" ""
integer "" 3 memberAttrName "" x-dimension
memberAttrName "" y-dimension integer "" 3
integer "" 5 memberAttrName "" y-dimension
endCollection "" "" integer "" 5
endCollection "" ""
Table 9 - Example Encoding of 1setOf collection Table 9 - Example Encoding of 1setOf collection
Octets Symbolic Value Protocol comments Octets Symbolic Value Protocol comments
field field
0x34 begCollection value-tag beginning of the "media-
size-supported (1setOf
collection" attribute
0x00014 name- length of (collection) 0x34 begCollection value-tag beginning of the "media-
length attribute name size-supported (1setOf
collection" attribute
media-size- media-size- name name of (collection) 0x00014 name- length of (collection)
supported supported attribute length attribute name
0x0000 value- defined to be 0 for this media-size- media-size- name name of (collection)
length type supported supported attribute
no value (since value- 0x0000 value- defined to be 0 for this
length was 0) length type
0x4A memberAttrName value-tag starts member attribute: no value (since value-
"x-dimension" length was 0)
0x0000 name- defined to be 0 for this 0x4A memberAttrName value-tag starts member attribute:
length type, so part of 1setOf "x-dimension"
no name (since name-length 0x0000 name- defined to be 0 for this
was 0) length type, so part of 1setOf
Octets Symbolic Value Protocol comments no name (since name-length
field was 0)
0x000B value- length of "x-dimension" 0x000B value- length of "x-dimension"
length keyword length keyword
x-dimension x-dimension value name of 1st collection x-dimension x-dimension value name of 1st collection
member attribute member attribute
0x21 integer type value-tag attribute type 0x21 integer type value-tag attribute type
0x0000 name- 0 indicates 1setOf 0x0000 name- 0 indicates 1setOf
length length
no name (since name-length no name (since name-length
was 0) was 0)
0x0004 value- length of an integer = 4 Octets Symbolic Value Protocol comments
length field
0x0006 value value of 1st collection 0x0004 value- length of an integer = 4
member attribute length
0x4A memberAttrName value-tag starts member attribute: 0x0006 value value of 1st collection
"y-dimension" member attribute
0x0000 name- defined to be 0 for this 0x4A memberAttrName value-tag starts member attribute:
length type, so part of 1setOf "y-dimension"
no name (since name-length 0x0000 name- defined to be 0 for this
was 0) length type, so part of 1setOf
0x000B value- length of the "y- no name (since name-length
length dimension" keyword was 0)
y-dimension y-dimension value name of 2nd collection 0x000B value- length of the "y-
member attribute length dimension" keyword
0x21 integer type value-tag attribute type y-dimension y-dimension value name of 2nd collection
member attribute
0x0000 name- 0 indicates 1setOf 0x21 integer type value-tag attribute type
length
no name (since name-length 0x0000 name- 0 indicates 1setOf
was 0) length
Octets Symbolic Value Protocol comments no name (since name-length
field was 0)
0x0004 value- length of an integer = 4 0x0004 value- length of an integer = 4
length length
0x0004 value value of 2nd collection 0x0004 value value of 2nd collection
member attribute member attribute
0x37 endCollection value-tag end of the collection 0x37 endCollection value-tag end of the collection
0x0000 name- defined to be 0 for this 0x0000 name- defined to be 0 for this
length type, so part of 1setOf length type, so part of 1setOf
no name (since name-length no name (since name-length
was 0) was 0)
0x0000 value- defined to be 0 for this Octets Symbolic Value Protocol comments
length type field
no value (since value- 0x0000 value- defined to be 0 for this
length was 0) length type
0x34 begCollection value-tag beginning of the 2nd no value (since value-
member of the 1SetOf length was 0)
"sizes-avail " collection
attribute
0x0000 name- Zero length name indicates 0x34 begCollection value-tag beginning of the 2nd
length this is member of previous member of the 1setOf
attribute "sizes-avail " collection
attribute
name no name (since name-length 0x0000 name- Zero length name indicates
was 0) length this is member of previous
attribute
0x0000 value- defined to be 0 for this name no name (since name-length
length type was 0)
no value (since value- 0x0000 value- defined to be 0 for this
length was 0) length type
0x4A memberAttrName value-tag starts member attribute: no value (since value-
"x-dimension" length was 0)
0x0000 name- defined to be 0 for this 0x4A memberAttrName value-tag starts member attribute:
length type, so part of 1setOf "x-dimension"
Octets Symbolic Value Protocol comments 0x0000 name- defined to be 0 for this
field length type, so part of 1setOf
no name (since name-length no name (since name-length
was 0) was 0)
0x000B value- length of "x-dimension" 0x000B value- length of "x-dimension"
length keyword length keyword
x-dimension x-dimension value name of 1st collection x-dimension x-dimension value name of 1st collection
member attribute member attribute
0x21 integer type value-tag attribute type 0x21 integer type value-tag attribute type
Octets Symbolic Value Protocol comments
field
0x0000 name- 0 indicates 1setOf 0x0000 name- 0 indicates 1setOf
length length
no name (since name-length no name (since name-length
was 0) was 0)
0x0004 value- length of an integer = 4 0x0004 value- length of an integer = 4
length length
0x0003 value value of 1st collection 0x0003 value value of 1st collection
member attribute member attribute
0x4A memberAttrName value-tag starts member attribute: 0x4A memberAttrName value-tag starts member attribute:
"y-dimension" "y-dimension"
0x0000 name- defined to be 0 for this 0x0000 name- defined to be 0 for this
length type, so part of 1setOf length type, so part of 1setOf
no name (since name-length no name (since name-length
was 0) was 0)
0x000B value- length of the "y- 0x000B value- length of the "y-
length dimension" keyword length dimension" keyword
y-dimension y-dimension value name of 2nd collection y-dimension y-dimension value name of 2nd collection
member attribute member attribute
0x21 integer type value-tag attribute type 0x21 integer type value-tag attribute type
0x0000 name- 0 indicates 1setOf 0x0000 name- 0 indicates 1setOf
length length
Octets Symbolic Value Protocol comments no name (since name-length
field was 0)
no name (since name-length 0x0004 value- length of an integer = 4
was 0) length
0x0004 value- length of an integer = 4 0x0005 value value of 2nd collection
length member attribute
0x0005 value value of 2nd collection Octets Symbolic Value Protocol comments
member attribute field
0x37 endCollection value-tag end of the 1setOf 0x37 endCollection value-tag end of the 1setOf
collection value collection value
0x0000 name- defined to be 0 for this 0x0000 name- defined to be 0 for this
length type, so part of 1setOf length type, so part of 1setOf
no name (since name-length no name (since name-length
was 0) was 0)
0x0000 value- defined to be 0 for this 0x0000 value- defined to be 0 for this
length type length type
no value (since value- no value (since value-
length was 0) length was 0)
16 Appendix C: Encoding Example of Collection containing 1setOf XXX Appendix C: Encoding Example of Collection containing 1setOf XXX
attribute attribute (Informative)
The overall structure of the collection value can be pictorially The overall structure of the collection value can be pictorially
represented as: represented as:
"wagons" = "wagons" =
{ "colors" = red, blue; { "colors" = red, blue;
"sizes" = 4, 6, 8 "sizes" = 4, 6, 8
} }
A simplified view of the encoding would look like this: A simplified view of the encoding would look like this:
Table 10 - Overview Encoding of collection with 1setOf value Table 10 - Overview Encoding of collection with 1setOf value
Tag Value Name Value Tag Value Name Value
begCollection wagons "" begCollection wagons ""
memberAttrName "" colors memberAttrName "" colors
keyword "" red keyword "" red
keyword "" blue keyword "" blue
memberAttrName "" sizes memberAttrName "" sizes
integer "" 4 integer "" 4
integer "" 6 integer "" 6
integer "" 8 integer "" 8
endCollection "" "" endCollection "" ""
Table 11 - Example Encoding of collection with 1setOf value Table 11 - Example Encoding of collection with 1setOf value
Octets Symbolic Value Protocol comments Octets Symbolic Value Protocol comments
field field
0x34 begCollection value-tag beginning of the "wagons" 0x34 begCollection value-tag beginning of the "wagons"
collection attribute collection attribute
0x0005 name- length of (collection) 0x0005 name- length of (collection)
length attribute name length attribute name
wagons wagons name name of (collection) wagons wagons name name of (collection)
attribute attribute
0x0000 value- defined to be 0 for this 0x0000 value- defined to be 0 for this
length type length type
no value (since value- no value (since value-
length was 0) length was 0)
Octets Symbolic Value Protocol comments 0x4A memberAttrName value-tag starts a new member
field attribute: "colors"
0x4A memberAttrName value-tag starts a new member 0x0000 name- defined to be 0 for this
attribute: "colors" length type, so part of 1setOf
0x0000 name- defined to be 0 for this no name (since name-length
length type, so part of 1setOf was 0)
no name (since name-length 0x0006 value- length of "colors" keyword
was 0) length
0x0006 value- length of "colors" keyword colors colors value value is name of 1st
length member attribute
colors colosr value value is name of 1st 0x44 keyword type value-tag keyword type
member attribute
0x44 keyword type value-tag keyword type 0x0000 name- 0 indicates 1setOf wagons
length
0x0000 name- 0 indicates 1setOf wagons no name (since name-length
length was 0)
no name (since name-length 0x0004 value-
was 0) length
0x0004 value- Octets Symbolic Value Protocol comments
length field
blue blue value value of 1st member blue blue value value of 1st member
attribute attribute
0x44 keyword type value-tag keyword type 0x44 keyword type value-tag keyword type
0x0000 name- 0 indicates 1setOf wagons 0x0000 name- 0 indicates 1setOf wagons
length length
no name (since name-length no name (since name-length
was 0) was 0)
0x0003 value- 0x0003 value-
length length
red red value value of 1st member red red value value of 1st member
attribute attribute
Octets Symbolic Value Protocol comments 0x4A memberAttrName value-tag starts a new member
field attribute: "sizes"
0x4A memberAttrName value-tag starts a new member 0x0000 name- defined to be 0 for this
attribute: "sizes" length type, so part of 1setOf
0x0000 name- defined to be 0 for this no name (since name-length
length type, so part of 1setOf was 0)
no name (since name-length 0x0005 value- length of "length-avail"
was 0) length keyword
0x0005 value- length of "length-avail" sizes sizes value Name of 2nd member
length keyword attribute
sizes sizes value Name of 2nd member 0x21 integer type value-tag attribute type
attribute
0x21 integer type value-tag attribute type 0x0000 name- 0 indicates 1setOf wagons
length
0x0000 name- 0 indicates 1setOf wagons no name (since name-length
length was 0)
no name (since name-length 0x0004 value- length of an integer = 4
was 0) length
0x0004 value- length of an integer = 4 Octets Symbolic Value Protocol comments
length field
0x0004 value 1st value for 1SetOf 0x0004 value 1st value for 1setOf
integer attribute integer attribute
0x21 integer type value-tag attribute type 0x21 integer type value-tag attribute type
0x0000 name- 0 indicates 1setOf 0x0000 name- 0 indicates 1setOf
length length
no name (since name-length no name (since name-length
was 0) was 0)
0x0004 value- length of an integer = 4 0x0004 value-
length length length of an integer = 4
0x0006 value 2nd value for 1SetOf 0x0006 value 2nd value for 1setOf
integer attribute integer attribute
Octets Symbolic Value Protocol comments 0x21 integer type value-tag attribute type
field
0x21 integer type value-tag attribute type 0x0000 name- 0 indicates 1setOf
length
0x0000 name- 0 indicates 1setOf no name (since name-length
length was 0)
no name (since name-length 0x0004 value- length of an integer = 4
was 0) length
0x0004 value- length of an integer = 4 0x0008 value 3rd value for 1setOf
length integer attribute
0x0008 value 3rd value for 1SetOf 0x37 endCollection value-tag end of the collection
integer attribute
0x37 endCollection value-tag end of the collection 0x0000 name- defined to be 0 for this
length type, so part of 1setOf
0x0000 name- defined to be 0 for this no name (since name-length
length type, so part of 1setOf was 0)
no name (since name-length 0x0000 value- defined to be 0 for this
was 0) length type
0x0000 value- defined to be 0 for this Octets Symbolic Value Protocol comments
length type field
no value (since value- no value (since value-
length was 0) length was 0)
17 Appendix D: Full Copyright Statement Appendix D: Description of the Base IPP Documents (Informative)
Copyright (C) The Internet Society (1998,1999,2000,2001). All Rights The base set of IPP documents includes:
Reserved
Design Goals for an Internet Printing Protocol [RFC2567]
Rationale for the Structure and Model and Protocol for the
Internet Printing Protocol [RFC2568]
Internet Printing Protocol/1.1: Model and Semantics [RFC2911]
Internet Printing Protocol/1.1: Encoding and Transport [RFC2910]
Internet Printing Protocol/1.1: Implementer's Guide [RFC3196]
Mapping between LPD and IPP Protocols [RFC2569]
The "Design Goals for an Internet Printing Protocol" document takes a
broad look at distributed printing functionality, and it enumerates
real-life scenarios that help to clarify the features that need to be
included in a printing protocol for the Internet. It identifies
requirements for three types of users: end users, operators, and
administrators. It calls out a subset of end user requirements that
are satisfied in IPP/1.0 [RFC2566, RFC2565]. A few OPTIONAL operator
operations have been added to IPP/1.1 [RFC2911, RFC2910].
The "Rationale for the Structure and Model and Protocol for the
Internet Printing Protocol" document describes IPP from a high level
view, defines a roadmap for the various documents that form the suite
of IPP specification documents, and gives background and rationale
for the IETF IPP working group's major decisions.
The "Internet Printing Protocol/1.1: Model and Semantics" document
describes a simplified model with abstract objects, their attributes,
and their operations. The model introduces a Printer and a Job. The
Job supports multiple documents per Job. The model document also
addresses how security, internationalization, and directory issues
are addressed.
The "Internet Printing Protocol/1.1: Encoding and Transport" document
is a formal mapping of the abstract operations and attributes defined
in the model document onto HTTP/1.1 [RFC2616]. It also defines the
encoding rules for a new Internet MIME media type called
"application/ipp". This document also defines the rules for
transporting over HTTP a message body whose Content-Type is
"application/ipp". This document defines the 'ipp' scheme for
identifying IPP printers and jobs.
The "Internet Printing Protocol/1.1: Implementer's Guide" document
gives insight and advice to implementers of IPP clients and IPP
objects. It is intended to help them understand IPP/1.1 and some of
the considerations that may assist them in the design of their client
and/or IPP object implementations. For example, a typical order of
processing requests is given, including error checking. Motivation
for some of the specification decisions is also included.
The "Mapping between LPD and IPP Protocols" document gives some
advice to implementers of gateways between IPP and LPD (Line Printer
Daemon) implementations.
Authors' Addresses
Roger deBry
Utah Valley State College
Orem, UT 84058
Phone: (801) 222-8000
EMail: debryro@uvsc.edu
Tom Hastings
Xerox Corporation
737 Hawaii St. ESAE 231
El Segundo, CA 90245
Phone: 310-333-6413
Fax: 310-333-5514
EMail: hastings@cp10.es.xerox.com
Robert Herriot
Consultant
706 Colorado Ave
Palo Alto, CA 94303
Phone: 650-327-4466
Fax: 650-327-4466
EMail: bob@herriot.com
Kirk Ocke
Xerox Corp.
800 Phillips Rd
M/S 128-30E
Webster, NY 14580
Phone: (585) 442-4832
EMail: KOcke@crt.xerox.com
Peter Zehler
Xerox Corp.
800 Phillips Rd
M/S 128-30E
Webster, NY 14580
Phone: (585) 265-8755
EMail: PZehler@crt.xerox.com
IPP Web Page: http://www.pwg.org/ipp/
IPP Mailing List: ipp@pwg.org
To subscribe to the ipp mailing list, send the following email:
1) send it to majordomo@pwg.org
2) leave the subject line blank
3) put the following two lines in the message body:
subscribe ipp
end
Implementers of this specification document are encouraged to join
the IPP Mailing List in order to participate in any discussions of
clarification issues and review of registration proposals for
additional attributes and values. In order to reduce spam the
mailing list rejects mail from non-subscribers, so you must subscribe
to the mailing list in order to send a question or comment to the
mailing list.
Full Copyright Statement
Copyright (C) The Internet Society (2002). All Rights Reserved.
This document and translations of it may be copied and furnished to This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of Internet organizations, except as needed for the purpose of
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The limited permissions granted above are perpetual and will not be The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns. revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Acknowledgement
Funding for the RFC Editor function is currently provided by the
Internet Society.
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