draft-ietf-ipp-collection-02.txt   draft-ietf-ipp-collection-03.txt 
INTERNET-DRAFT Roger deBry INTERNET-DRAFT Roger deBry
<draft-ietf-ipp-collection-02.txt> Utah Valley State College <draft-ietf-ipp-collection-03.txt> Utah Valley State College
T. Hastings T. Hastings
Xerox Corporation Xerox Corporation
R. Herriot R. Herriot
Xerox Corporation Xerox Corporation
K. Ocke K. Ocke
Xerox Corporation Xerox Corporation
P. Zehler P. Zehler
Xerox Corporation Xerox Corporation
March 9, 2000 June 29, 2000
Internet Printing Protocol (IPP): Internet Printing Protocol (IPP):
The 'collection' attribute syntax The 'collection' attribute syntax
Copyright (C) The Internet Society (2000). All Rights Reserved. Copyright (C) The Internet Society (2000). All Rights Reserved.
Status of this Memo: Status of this Memo:
This document is an Internet-Draft and is in full conformance with all This document is an Internet-Draft and is in full conformance with all
provisions of Section 10 of [RFC2026]. Internet-Drafts are working provisions of Section 10 of [RFC2026]. Internet-Drafts are working
skipping to change at page 1, line 46 skipping to change at page 2, line ?
http://www.ietf.org/shadow.html. http://www.ietf.org/shadow.html.
Abstract Abstract
This document specifies an OPTIONAL attribute syntax called This document specifies an OPTIONAL attribute syntax called
'collection' for use with the Internet Printing Protocol/1.0 'collection' for use with the Internet Printing Protocol/1.0
(IPP) [RFC2565, RFC2566], IPP/1.1 [ipp-mod, ipp-pro], and (IPP) [RFC2565, RFC2566], IPP/1.1 [ipp-mod, ipp-pro], and
subsequent versions. A 'collection' is a container holding one or subsequent versions. A 'collection' is a container holding one or
more named values, which are called "member" attributes. A more named values, which are called "member" attributes. A
collection allows data to be grouped like a PostScript dictionary collection allows data to be grouped like a PostScript dictionary
or a Java Map. or a Java Map. This document also specifies the conformance
requirements for a definition document that defines a collection
There are 4 issues in the document. attribute.
[Expires: September 9, 2000] deBry, Hastings, Herriot, Ocke, Zehler Expires: December 29, 2000 [1]
The full set of IPP documents includes: The full set of IPP documents includes:
Design Goals for an Internet Printing Protocol [RFC2567] Design Goals for an Internet Printing Protocol [RFC2567]
Rationale for the Structure and Model and Protocol for the Internet Rationale for the Structure and Model and Protocol for the Internet
Printing Protocol [RFC2568] Printing Protocol [RFC2568]
Internet Printing Protocol/1.1: Model and Semantics (this document) Internet Printing Protocol/1.1: Model and Semantics (this document)
Internet Printing Protocol/1.1: Encoding and Transport [IPP-PRO] Internet Printing Protocol/1.1: Encoding and Transport [IPP-PRO]
Internet Printing Protocol/1.1: Implementer's Guide [IPP-IIG] Internet Printing Protocol/1.1: Implementer's Guide [IPP-IIG]
Mapping between LPD and IPP Protocols [RFC2569] Mapping between LPD and IPP Protocols [RFC2569]
skipping to change at page 3, line 5 skipping to change at page 3, line 5
is intended to help them understand IPP/1.1 and some of the 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 considerations that may assist them in the design of their client and/or
IPP object implementations. For example, a typical order of processing IPP object implementations. For example, a typical order of processing
requests is given, including error checking. Motivation for some of the requests is given, including error checking. Motivation for some of the
specification decisions is also included. specification decisions is also included.
The "Mapping between LPD and IPP Protocols" document gives some advice The "Mapping between LPD and IPP Protocols" document gives some advice
to implementers of gateways between IPP and LPD (Line Printer Daemon) to implementers of gateways between IPP and LPD (Line Printer Daemon)
implementations. implementations.
[Expires: September 9, 2000]
Table of Contents Table of Contents
1 Problem Statement.................................................4 1 Problem Statement.................................................5
2 Solution..........................................................4 2 Solution..........................................................5
3 Definition of a Collection Attribute..............................5 3 Definition of a Collection Attribute..............................6
3.1 Member Attribute Naming Rules..................................5 3.1 Information to Include.........................................6
3.2 Remaining rules for a collection attribute definition..........6 3.2 Nested Collections.............................................9
3.3 Nested Collections.............................................8 4 Collection Attributes as Attributes in Operations.................9
3.4 Collection Attributes as Operation Attributes..................9 4.1 General Rules..................................................9
3.5 Collections as Job Template Attributes.........................9 4.2 Unsupported Values.............................................9
3.6 Collections and Get-Printer-Attributes and Get-Job-Attributes 5 Example definition of a collection attribute.....................10
operations.........................................................10 5.1 media-col (collection)........................................10
4 New Out-of-band value............................................11 5.1.1media-color (type3 keyword | name(MAX)......................11
4.1 'none'........................................................11 5.1.2media-size (collection).....................................11
5 Unsupported Values...............................................12 5.2 media-col-default (collection)................................12
6 Sample specification.............................................12 5.3 media-col-ready (1setOf collection)...........................12
5.4 media-col-supported (1setOf type2 keyword)....................12
6 A Second Example Definition Of A Collection Attribute............12
7 Encoding.........................................................13 7 Encoding.........................................................13
7.1 encoding of a collection (using solution 1a)..................17 7.1 Additional tags defined for representing a collection attribute
7.2 Sample Encoding (using solution 1a)...........................19 value..............................................................13
7.3 1setOf Collection encoding (using solution 1a)................20 7.2 Example encoding: "media-col" (collection)....................14
7.4 Sample 1setOf Collection encoding (using solution 1a).........21 8 Legacy issues....................................................17
8 Legacy issues....................................................23 9 IANA Considerations..............................................18
9 IANA Considerations..............................................24 10 Internationalization Considerations..............................18
10 Internationalization Considerations..............................24 11 Security Considerations..........................................18
11 Security Considerations..........................................24 12 References.......................................................18
12 References.......................................................24 13 Author's Addresses...............................................19
13 Author's Addresses...............................................25 14 Appendix A: Encoding Example of a Simple Collection..............20
14 Appendix A: Full Copyright Statement.............................26 15 Appendix B: Encoding Example of 1setOf Collection................22
16 Appendix C: Encoding Example of Collection containing 1setOf XXX
attribute............................................................26
17 Appendix D: Full Copyright Statement.............................28
[Expires: September 9, 2000] Table of Tables
Table 1 - "media-col" member attributes..............................11
Table 2 - "media-size" collection member attributes..................11
Table 3 - Tags defined for encoding the 'collection' attribute syntax13
Table 4 - Overview Encoding of "media-col" collection................15
Table 5 - Example Encoding of "media-col" collection.................15
Table 6 - Overview Encoding of simple collection.....................21
Table 7 - Example Encoding of simple collection......................21
Table 8 - Overview Encoding of 1setOf collection.....................23
Table 9 - Example Encoding of 1setOf collection......................23
Table 10 - Overview Encoding of collection with 1setOf value.........26
Table 11 - Example Encoding of collection with 1setOf value..........26
1 Problem Statement 1 Problem Statement
The IPP Model and Semantics [ipp-mod] supports most of the common data The IPP Model and Semantics [ipp-mod] supports most of the common data
structures that are available in programming languages. It lacks a structures that are available in programming languages. It lacks a
mechanism for grouping several attributes of different types. The Java mechanism for grouping several attributes of different types. The Java
language uses the Map to solve this problem and PostScript has a language uses the Map to solve this problem and PostScript has a
dictionary. The new mechanism for grouping attributes together must dictionary. The new mechanism for grouping attributes together (called
allow for optional members and subsequent extension of the collection. 'collection' mechanism) must allow for optional members and subsequent
addition of new members.
The mechanism must be encoded in a manner consistent with existing 1.0 The 'collection' mechanism must be encoded in a manner consistent with
and 1.1 parsing rules (see [ipp-pro]). Current 1.0 and 1.1 parsers that existing 1.0 and 1.1 parsing rules (see [ipp-pro]). Current 1.0 and 1.1
don't support collections should not confuse collections they receive parsers that don't support the 'collection' mechanism must not confuse
with attributes that they do support. collections or parts of collection they receive with other attributes.
2 Solution 2 Solution
The new mechanism is a new IPP attribute syntax called a 'collection'. The new mechanism is a new IPP attribute syntax called a 'collection'.
As such each collection value is a value of an attribute whose attribute As such, each collection value is a value of an attribute whose
syntax type is defined to be a 'collection'. Such an attribute is attribute syntax type is defined to be a 'collection'. Such an
called a collection attribute. The name of the collection attribute attribute is called a collection attribute. The name of the collection
serves to identify the collection value in an operation request or attribute serves to identify the collection value in an operation
response, as with any attribute value. request or response, as with any 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 value optional member attributes of each collection value. A collection value
is similar to an IPP attribute group in a request or a response, such as is similar to an IPP attribute group in a request or a response, such as
the operation attributes group. They both consist of a set of the operation attributes group. They both consist of a set of
attributes. attributes.
As with any attribute syntax, the collection attribute definition As with any attribute syntax, the document that defines a collection
document specifies whether the attribute is single-value (collection) or attribute specifies whether the attribute is single-value (collection)
multi-valued (1setOf collection). or multi-valued (1setOf collection). If the attribute is multi-valued
(1setOf collection) each collection value MUST be a separate instance of
a single definition of a collection, i.e. it MUST have the same member
attributes except for OPTIONAL member attributes. If we view each
collection definition as a separate 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 pattern). Without this rule, the supported values
would be more difficult to describe and the mechanism defined in item 4
of section 3.1would not be sufficient.
The name of each member attribute MUST be unique, but MAY be the same as The name of each member attribute MUST be unique for a collection
the name of a member attribute in another collection type and/or MAY be attribute, but MAY be the same as the name of a member attribute in
the same as the name of an attribute that is not a member of a another collection attribute and/or MAY be the same as the name of an
collection.. The rules for naming member attributes are given in attribute that is not a member of a collection. The rules for naming
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 each length of a collection value is not limited. However, the length of each
member attribute MUST NOT exceed the limit of its attribute syntax. member attribute MUST NOT exceed the limit of its attribute syntax.
The member attributes in a collection MAY be in any order in a request The member attributes in a collection MAY be in any order in a request
or response. When a client sends a collection attribute to the Printer, or response. When a client sends a collection attribute to the Printer,
[Expires: September 9, 2000]
the order that the Printer stores the member attributes of the the order that the Printer stores the member attributes of the
collection value and the order returned in a response MAY be different collection value and the order returned in a response MAY be different
from the order sent by the client. from the order sent by the client.
A collection value MUST NOT contains two or more member attributes with A collection value MUST NOT contains two or more member attributes with
the same attribute name. Such a collection is mal-formed. Clients MUST the same attribute name. Such a collection is mal-formed. Clients MUST
NOT submit such malformed requests and Printers MUST NOT return such NOT submit such malformed requests and Printers MUST NOT return such
malformed responses. If such a malformed request is submitted to a malformed responses. If such a malformed request is submitted to a
Printer, the Printer MUST reject the request with the 'client-error-bad- Printer, the Printer MUST (depending on implementation) either (1)
request' status code (see section 13.1.4.1) reject the request with the 'client-error-bad-request' status code (see
section 13.1.4.1), or (2) accept the request and use only one of each
ISSUE 01: In attribute groups [ipp-mod] allows a Printer either (1) to duplicate member attribute..
reject a request with duplicate named attributes OR (2) to choose
exactly one of the attributes as the one to be used. Should we REQUIRE
the Printer to reject duplicate named attributes in a collection value
as stated above or allow the Printer to choose one member attribute as a
second alternative as we do with attribute groups?
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 Member Attribute Naming Rules 3.1 Information to Include
Each collection attribute MUST have a unique name within the scope in
which the collection attribute occurs. If the collection attribute
occurs as a member of a request or response attribute group, it MUST be
unique within that group, same as for any other attribute. If a
collection attribute occurs as a member attribute of another collection,
the collection attribute MUST have a unique name within that collection
value, same as for any other attribute.
Each member attribute in a collection value MUST have unique name within
that collection value. Member attribute names MAY be reused between
different collection attributes. An example is the "media" attribute
which MAY be used as a job template attribute (see [ipp-mod]) and in a
collection. All attribute names that are reused MUST have an identical
syntax. All attribute names that are reused MUST have a similar
semantics. The semantic difference MUST be limited to boundary
conditions and constraints placed on the reused attributes. All
attributes that are not reused from elsewhere in the IPP model MUST have
a globally unique name.
Assume that it is desirable to extend IPP by adding a Job Template
attribute that allows the client to select the media by its properties,
e.g., weight, color, size, etc., instead of by name as the "media (type3
keyword | name) Job Template attribute in IPP/1.1 (see [ipp-mod]). The
first rule is that the existing attribute MUST NOT be extended by adding
the 'collection' attribute syntax to the existing "media" attribute.
That would cause too many interoperability problems and complicates the
[Expires: September 9, 2000]
validation and defaulting rules as well. Instead, a new attribute will
be defined with a suffix of "-col" (for collection), e.g., "media-col"
(collection).
For a second example, suppose it is desirable to extend IPP by allowing
the client to select the media for the job start sheet. Again, this
would not be done by adding the 'collection' attribute syntax to the
existing "job-sheets" (type2 keyword | name) Job Template attribute.
Instead, a new "job-sheet-col" (collection) Job Template attribute MUST
be introduced. The member of the "job-sheet-col" collection might be:
"job-sheet-format" (type3 keyword | name)
"media" (type3 keyword | name)
if any of the "media-supported" (1setOf (type3 keyword | name)) Printer
attribute values could be specified for job sheets. The reason that the
"job-sheet-format" member attribute isn't named simply, "job-sheet", is
because its values only indicate the format, and don't imply any media,
while the "job-sheets" (type2 keyword | name) Job Template attribute do
imply a media. This example illustrates when a member attribute can be
the same as another attribute (in this case a Job Template attribute)
and when the member attribute MUST have a different name.
If the definers of the "job-sheet-col" (collection) attribute intended
that the System Administrator be allowed to have a different set of
media values for job sheets than documents, then the definition document
for the "job-sheet-col" collection attribute would have the following
member attributes instead:
"job-sheet-format" (type3 keyword | name)
"job-sheet-media" (type3 keyword | name)
Then the supported values would be include in a separate "job-sheet-
media-supported" (1setOf (type3 keyword | name)) Printer attribute.
3.2 Remaining rules for a collection attribute definition
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 following '1setOf collection'; the definition document MUST include the following
aspects of the attribute semantics. Suppose the "xxx" collection aspects of the attribute semantics. Suppose the "xxx" collection
attribute contains an "aaa" member attribute. A simplified example of a attribute contains N member attributes named "aaa1", "aaa2", ., "aaaN"
collection specification is given in section 6 ("aaaI" represents any one of these N member 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") "xxx"). The selection of the name "xxx" MUST follow the same rules
for uniqueness as for attributes of any other syntax type (as
defined by IPP/1.1) unless "xxx" is a member attribute of another
collection. Then the selection of the name "xxx" MUST 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
[Expires: September 9, 2000]
attribute, a member attribute of a particular collection attribute, attribute, a member attribute of a particular collection attribute,
etc. etc.
4. The member attributes MUST be defined. For each member attribute 4. An "xxx-supported" attribute MUST be specified and it has one of
the definition document MUST provide the following: the following two forms:
a)The member attribute's name, "aaa", MUST either (1) reuse the
attribute name of another attribute if the member attribute
shares the syntax and semantics with the other attribute or (2)
be unique across the entire IPP attribute name space
b)Whether the member attribute is REQUIRED or OPTIONAL for the
Printer to support
c)Whether the member attribute is REQUIRED or OPTIONAL for the
client to supply in a request
d)The member attribute's syntax type, which can be any attribute
syntax, including '1setOf X', 'collection', and '1setOf
collection'. If this attribute name is the same as another
attribute (case of option a-1 above), it MUST have the same
attribute syntax, including cardinality (1setOf or not).
e)The semantics of the "aaa" member attribute. The semantic
definition MUST include a description of any constraint or
boundary conditions the member attribute places on the
associated attribute, especially if the attribute is the same as
another attribute used in a different context (case of option a-
1 above)
f)the supported values for the "aaa" member attribute, either
enumerated explicitly or specified by the values of a referenced
attribute which may be specified by either:
@ the attribute's definition
@ a Printer attribute, such as "aaa-supported", which
contains the explicit values supported. The "aaa-supported"
attribute is a Printer attribute and not in a collection.
For example, if a collection contains the "media" attribute
and its supported values are specified by the "media-
supported" attribute, the "media-supported" attribute is
the same Printer attribute that the "media" attribute uses.
g)the default value of "aaa" member attribute if it is OPTIONAL
for a client to supply the "aaa" member attribute in a request.
The default value is specified by either:
@ the attribute's definition
@ a Printer attribute, such as "aaa-default", which may have a)"xxx-supported" is a "1setOf collection" which enumerates all of
a collection value the supported collection values of "xxx". If a collection of
this form contains a nested collection, it MUST be of the same
form.
[Expires: September 9, 2000] For example, "media-size-supported" might have the values {{x-
@ or an implementation defined algorithm that takes into dimension:210, y-dimension:297},{x-dimension:297, y-
account the values of the other member attributes of the dimension:420}} to show that it supports two values of "media
collection value size": A4 (210x297) and A3 (297x420). It does not support other
combinations of "x-dimension" and "y-dimension" member
attributes, such as 210x420 or 297x297 and it does not supported
non-enumerated values, such as 420x595.
h)Depending on the collection attributes context, it MUST follow b)"xxx-supported" is a "1setOf type2 keyword" which enumerates
the additional rules specified below for the various contexts. the names of all of the member attributes of "xxx": "aaa1",
"aaa2", ., "aaaN". If a collection of this form contains a
nested collection, it MAY be of either form. See item 5f) below
for details on supported values of member attributes.
3.3 Nested Collections For example, "media-col-supported" might have the keyword
values: "media-size" and "media-color".
A member attribute may have a syntax type of 'collection' or '1setOf 5. The member attributes MUST be defined. For each member attribute
collection'. The following example assumes a "yyy" collection attribute the definition document MUST provide the following information:
is a member attribute of the preceding "xxx" collection attribute. The
"yyy" collection attribute contains "bbb" member attribute. The
definition document for the nested collection MUST include:
1.The name of the collection attribute, e.g., "yyy" a)The member attribute's name (e.g., "aaa") MUST be unique within
the collection being defined and MUST either
2.The collection attribute syntax MUST be of type 'collection' or i) reuse the attribute name of another attribute (that is unique
'1setOf collection' across the entire IPP attribute name space) and have the same
syntax and semantics as the reused attribute (if the condition
of item 4b) above is met). For example, a member attribute
definition could reuse the IPP/1.1 "media" attribute.
3.The member attributes MUST be defined. For each member attribute the ii) potentially occur elsewhere in the entire IPP attribute
definition document MUST provide the following: name space. (if the condition of item 4a) above is met). For
example, a member attribute could be "x-dimension" which could
potentially occur in another collection or as an attribute
outside of a collection.
a) The member attribute's name, "bbb", MUST either (1) reuse the iii) be unique across the entire IPP attribute name space (if
attribute name of another attribute if the member attribute shares the condition of item 4b) above is met). For example, a member
the syntax and semantics with the other attribute or (2) be unique attribute could be "media-color" which must unique be across
across the entire IPP attribute name space 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 client c)Whether the member attribute is REQUIRED or OPTIONAL for the
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 is the same as another collection'. If this attribute name reuses the name of another
attribute (case of option a-1 above), it MUST have the same attribute (case of item a1 above), it MUST have the same
attribute syntax, including cardinality (1setOf or not) attribute syntax, including cardinality (whether or not 1setOf).
e) The semantics of the member attribute. The semantic definition MUST
include a description of any constraint or boundary conditions the
member attribute places on the associated attribute, especially if
the attribute is the same as another attribute used in a different
context (case of option a-1 above)
f)
g) Depending on the collection attributes context, it MUST follow the
additional rules specified below for the various contexts.
[Expires: September 9, 2000]
3.4 Collection Attributes as Operation Attributes
The definition documents that define a collection attribute for use as
an operation attribute MUST follow these additional rules:
a)Define in which operation requests the collection attribute is
intended to be used.
b)Define in which operation responses the collection attribute is
intended to be used.
3.5 Collections as Job Template Attributes
The definition documents for collection attributes that are specified to
be Job Template attributes (see [ipp-mod] section 4.2) MUST have
associated printer attributes with suffixes of "-supported" and "-
default" (or indicate that there is no "-default"), just as for any Job
Template attribute. Certain Job Template collection attributes also
have an associated Printer attribute with "-ready" (for example, see the
"media-ready" attribute in [ipp-mod]). Furthermore member attributes of
job template attributes are addressed using the same suffix convention.
See also section 3.6 on the interaction of collections and the Get-
Printer-Attributes and Get-Jobs-Attributes.
For the following rules assume the "xxx" (collection) example from
section 3.2 is a job template attribute.
1)There MUST be two associated printer attributes. The attributes are
"xxx-supported" and "xxx-default"
2)The "xxx-default" is a collection with a syntax identical to the
"xxx" specification in section 3.2 .
@ Each member attribute has the same name as in the "xxx"
definition.
@ A Get-Printer-Attributes operation MUST return the "xxx-default"
(collection) Printer attribute and all the member attributes.
Any default values that have been set MUST be returned. Any
default values that have not been set MUST return an out of band
attribute of 'no-value'.
3.If the definition of the collection does not mention an "xxx-ready"
attribute than it is assumed that one is not defined, though
implementer's are free to support an "xxx-ready" as an extension.
4.The collection attribute definition document MUST define an "xxx- e)The semantics of the "aaa" member attribute. The semantic
supported" attribute with either a syntax of '1setOf type2 keyword' definition MUST include a description of any constraint or
or '1setOf collection': boundary conditions the member attribute places on the
associated attribute, especially if the attribute reuses the
name of another attribute (case of item a1 above)
[Expires: September 9, 2000] f)The supported values for the each "aaaI" member attribute (of
@ If the definition uses the '1setOf type2 keyword' attribute the member attributes "aaa1", "aaa2", ., "aaaN") is specified
syntax, it MUST be the attribute keyword names of all of the by one of two mechanisms.
member attributes that the Printer implementation supports in a
Job Creation operation. Furthermore, the definition MUST
include corresponding definitions of each of the "aaa-supported"
attributes that correspond to each "aaa" member attribute. Then
a client can determine the supported values of each member
attribute in the Job Template collection attribute
@ If the definition uses the '1setOf collection' attribute syntax, i) If "xxx-supported" is a "1setOf collection" (see item 4a)
then the values are the supported instances of the "xxx" above), the value for each "aaaI" is specified in each
(collection) attribute that a client can supply in a Job collection value of "xxx-supported" in the context of other
Creation operation. It is expected that this second approach member attributes. That is, "xxx-supported" enumerates all
will be used for small collections whether the number of supported values of "xxx".
possible collection values is small. For example, a "media-
size" (collection) member attribute in which the member
attributes are "x-dimension" (integer) and "y-dimension"
(integer). The pairs of integers are just like keywords as far
as the client localization is concerned, except that if the
client doesn't recognize a size pair of numbers, it can display
the numbers.
a) The keywords returned lists all the contained member attribute ii) If the value of "xxx-supported" is a "1setOf type2
names. This example would return the "aaa" keyword. keyword" (see item 4b) above), the supported values of "aaaI"
are the values specified by either i) the "aaaI-supported"
attribute or ii) the definition of the member attribute "aaaI"
within the document defining the "xxx" attribute. The values
of each member attribute "aaaI" are specified independently of
other member attributes though a Printer is not required to
support all combinations of supported values.
b) The list is recursive and lists all the member attributes of the For example, "media-col-supported" might have the keyword
contained collections. In section 3.3 the printer would return values: "media-size" and "media-color". Using the first method
"aaa" and "bbb" for collection "xxx" for defining supported values (an "aaaI-supported" attribute),
the collection values of "media-col" are combinations of
values of "media-size-supported" and "media-color-
supported".If "media-size-supported" has the values of
'210x297' and '297x420' and "media-color-supported" has the
values of 'white' and 'pink', the Printer might support only
the combinations 'white-210x297', 'pink-210x297'and 'white-
297x420', and not 'pink-297x420'.
c) The encoding convention allows the reconstruction of the collection If a collection contains a member "aaaI" whose syntax type is
structure. The will allow the client to reconstruct the "text", the supported values would probably be defined by the
collections. The client would know that "aaa" is a member of definition of "xxx" rather than by the attribute "aaaI-
collection "xxx". It can also be derived that collection "bbb" is supported".
a member of collection "yyy". See section 7 for more information
on encoding.
d) To obtain the supported values for any member attribute a client g)the default value of each "aaaI" member attribute if it is
performs a Get-Printer-Attributes operation explicitly requesting OPTIONAL for a client to supply the "aaa" member attribute in a
the member attribute name with the suffix "supported". If a member request. The default value is specified by in the attribute's
attribute is itself a collection rule 4 above applies to member definition within a document and MUST be one of the following:
attribute.
3.6 Collections and Get-Printer-Attributes and Get-Job-Attributes i) a fixed default
operations
The behavior of collections for "job-description" and "printer- ii) a mechanism by which the Printer determines default
description" is similar to any other attribute. Simple attributes iii) an indefinite default that is left to the implementation.
return the attribute and its value. For a collection, the collection
and its entire member attributes and their values are returned. This
includes any containing collections, its member attributes and their
values. The same logic applies for the "-default" and "-ready" printer
attribute associated with a job-template attributes.
[Expires: September 9, 2000] iv) an attribute that the Printer uses to determine the default
Whether the Printer applies individual member attributes independently 6. The default value of "xxx" if a client does not supply it. The
or takes into account the member attributes supplied by the client in default value is specified by in the attribute's definition within
the collection, depends on implementation. Therefore, a client SHOULD a document and MUST be one of the following:
query the Printer's "xxx-default" (collection) attribute, allow the user
to make any changes, and then submit the entire collection to the
Printer. Then the variability in defaulting between different
implementations will not cause the user to get unexpected results.
The semantics for "-supported" is different for a collection. Here the a)a fixed default
focus is on the member attributes that the collection supports. This
solution allows for extension of collections and allowing the member
attributes of a collection to vary (i.e. mandatory and optional member
attributes). Once a client determines what member attributes are
supported in a collection a subsequent request can be constructed to
determine the supported values for the member attributes.
Another advantage of that the behavior of the "-supported" printer b)a mechanism by which the Printer determines default
collection attribute is limiting the amount of data that is returned on
general queries. A 'get-printer-attributes' that returns all the
attributes of a printer will not have to return what may turn out to be
extensive lists of "-supported" attribute values. An example might be
"media-col" that could be a representation for media using a collection
that goes beyond the information currently provided by the job-template
attribute "media". The "media-col" could now be used to represent a
job's media, insert sheets and inserted tab sheets. An IPP Printer
implementation would return the member attributes for each of the "-
supported" collections.
4 New Out-of-band value c)an indefinite default that is left to the implementation
4.1 'none' d)a Printer attribute "xxx-default" which is a collection with the
same member attributes as "xxx". Though optional member
attributes may be absent in which case the Printer uses the
defaulting rules of item 5g) above.
'none' The specified Job Template attribute in the request MUST 7. The "xxx-ready (1setOf collection)" attribute if human intervention
NOT be applied to the job. Specifically, this value is required to make many of the supported values available. For
overrides the Printer's "xxx-default" attribute value for example, "media-col" is an attribute which has a "ready" attribute.
the Job Template attribute, if one exists. Most attributes do not have a "ready" attribute.
This "out-of-band" value allows a client to specify "turn-off" a feature 3.2 Nested Collections
that is specified by an attribute whose value is a collection. Because a
client specifies a value, the Printer uses the client-specified value
and not the Printer's default value.
If a Printer supports the use of the 'collection' attribute syntax for A member attribute may have a syntax type of 'collection' or '1setOf
an attribute, a Printer MUST support the use of the "out-of-band" value collection', in which case it is called a nested collection attribute.
'none'. The rules for a nested collection attribute are the same as for a
collection attribute as specified in section 3.1.
A Printer MUST support the "out-of-band" value 'none' as the value for 4 Collection Attributes as Attributes in Operations
an attribute "xxx" if:
[Expires: September 9, 2000] 4.1 General Rules
@ the definition of the attribute specifies 'none' MUST be
supported AND
@ the definition of the attribute specifies 'none' MAY be A collection value is like any other IPP/1.1 value, except that it is
supported and it is a value of the attribute "xxx-supported". structured. The rules for attributes with collection values are the same
as for attributes of any other syntax type (see IPP/1.1), be they in any
group of a request of a response.
5 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:
If the entire collection attribute is unsupported, then the Printer
returns just the collection attribute name with the 'unsupported'
out-of-band value (see the beginning of [ipp-mod] section 4.1) in the
Unsupported Attributes Group.
If a collection contains unrecognized, unsupported member attributes
and/or conflicting values, the attribute returned in the Unsupported
Group is a collection containing the unrecognized, unsupported member
attributes, and/or conflicting values. The unrecognized member
attributes have an out-of-band value of 'unsupported' (see the
beginning of [ipp-mod] section 4.1). The unsupported member
attributes and conflicting values have their unsupported or
conflicting values.
6 Sample specification
This example is for a collection called "media-col". The "media-col"
attribute is a job template attribute. This collection is simplified
and fictitious and is used for illustrative purposes only.
Name: media-col
Syntax: collection
Member Attributes:
Name: "media-color"
Syntax: type3 keyword | name
Mandatory
Semantics: This attribute identifies the color of the media. Valid
values are "red" "white" and "blue"
"media-color-supported" syntax: 1setOf (type2 keyword | name)
Name: "media-size"
[Expires: September 9, 2000]
Syntax: collection
Member Attributes:
Name: "x-dimension"
Syntax: integer
Mandatory
Semantics: This attribute identifies length of the media in
inches. Valid values are any integer though in practice
implementation will constrain the range.
x-supported syntax: rangeOfInteger
Name: "y-dimension"
Syntax: integer
Mandatory
Semantics: This attribute identifies the width of the media in
inches. Valid values are any integer though in practice
implementation will constrain the range.
y-supported syntax: rangeOfInteger
Name: name
Syntax: See job template attribute "media" 1. If the entire collection attribute is unsupported, then the
Printer returns just the collection attribute name with the
'unsupported' out-of-band value (see the beginning of [ipp-mod]
section 4.1) in the Unsupported Attributes Group.
Optional 2. If a collection contains unrecognized, unsupported member
attributes and/or conflicting values, the attribute returned in
the Unsupported Group is a collection containing the
unrecognized, unsupported member attributes, and/or conflicting
values. The unrecognized member attributes have an out-of-band
value of 'unsupported' (see the beginning of [ipp-mod] section
4.1). The unsupported member attributes and conflicting values
have their unsupported or conflicting values.
Semantics: See job template attribute "media". Additional 5 Example definition of a collection attribute
restrictions on "media" in this collection are that the "media"
value must be valid based on the size and color. When invalid
names are given based on the size or color, the size or color value
takes precedence.
Supported values identical to job template attribute "media- In some printing environments, it is desirable to allow the client to
supported". select the media by its properties, e.g., weight, color, size, etc.,
instead of by name. In IPP/1.1 (see [ipp-mod]), the "media (type3
keyword | name) Job Template attribute allows selection by name. It is
tempting to extend the "media" attribute syntax to include "collection",
but then existing clients could not understand default or supported
media values that use the collection value. To preserve
interoperability, a new attribute MUST BE added, e.g., "media-col
(collection)". The following subsections contain a sample definition of
a simplified "media-col" attribute. The definition follows the rules in
section 3.
7 Encoding Note: we picked the name "media-col" because the name "media" is already
in use. Ordinarily the collection attribute would have a name like any
other attribute and would not end in "col".
This section is still under construction. The member attributes of "media-col" attribute ("media-color (type 3
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 IPP
attribute name space. The member attributes of the "media-size
(collection)" member attribute ("x-dimension (integer(0,MAX))" and "y-
dimension (integer(0,MAX))") both follow the naming rules of item 4a2 of
section 3, i.e. they potentially occur elsewhere in the IPP attribute
name space.
We are now down to considering two encodings for collections. The goals 5.1 media-col (collection)
of the encoding are:
[Expires: September 9, 2000] The "media-col" (collection) attribute augments the IPP/1.1 [ipp-mod]
a) must be simple "media" attribute. This collection attribute enables a client end user
to submit a list of media characteristics to the Printer. When the
client specifies media using the "media-col" collection attribute, the
Printer object MUST match the requested media exactly. The 'collection'
consists of the following member attributes:
b) a legacy receiver must correctly ignore a collection value and not Table 1 - "media-col" member attributes
incorrectly decode part of a collection as a legitimate attribute.
c) it parses an attributes with collection values as a single unknown Attribute name attribute syntax request Printer
attribute rather than as many unknown attributes. Support
The two encodings are: media-color type3 keyword | name (MAX) MAY MUST
1) encode attributes within collections in the same way as media-size collection MUST MUST
attributes outside of collections, but encode each attribute name
in a collection so that its name cannot be the same as an attribute
name outside of a collection. We have considered two solutions for
encoding attribute names.
a) add a prefix to each collection member attribute name where The definitions for the member attributes is given in the following
the prefix is the (outer) attribute's name following by a dot
("."). Nested collections have extra levels of dotted names.
For example, the "media-size" attribute in "media-col" is
encoded as "media-col.media-size" and the "x" attribute in
"media-size" which is inside "media" is encoded as "media-
col.media-size.x". The outer attribute name is the "name" of
the begin-collection and end-collection value.
b) add a hyphen suffix to each attribute name in a collection. sub-sections:
For example, the "media-size" attribute in "media-col" is
encoded as "media-size-" and the "x" attribute in "media-size"
which is inside "media" is encoded as "x-". Note the hyphen
must be a suffix so that the attribute name follows the rules
for a legal keyword, and the hyphen is chosen because no
attributes currently end with a hyphen. The empty name is used
for the end-collection value and all but the first begin-
collection value.
2) encode attributes within a collection as a 1setOf values where 5.1.1 media-color (type3 keyword | name(MAX)
each attribute whose name is M and whose values are V1 ... Vn are
encoded as a sequence of n+1 values M, V1, ... Vn. Subsequent
member attributes continue the value in the 1setOf values.
The following are examples of encodings. In the real encoding, each This member attribute identifies the color of the media. Valid
"attribute" consists of values are 'red', 'white' and 'blue'
a) a one byte tag The "media-color-supported" (1setOf (type3 keyword | name(MAX)))
Printer attribute identifies the values of this "media-color"
member attribute that the Printer supports, i.e., the colors
supported.
b) a two byte name length whose value is "n" If the client omits this member attribute, the Printer determines
the value in an implementation dependent manner.
c) "n" bytes of a name 5.1.2 media-size (collection)
d) a two bytes value length whose value is "v" This member attribute identifies the size of the media. The
'collection' consists of the member attributes shown in Table 2:
e) "v" bytes of a value Table 2 - "media-size" collection member attributes
[Expires: September 9, 2000] Attribute attribute syntax request Printer
name Support
To make it easy to read, we show only items c (the name), a (the tag) x-dimension integer (0:MAX) MUST MUST
and e (the value), in that order.
There are 3 encoding examples for each solution: y-dimension integer (0:MAX) MUST MUST
i) media-col with media-color and media-size as member attributes, The definitions for the member attributes is given in the
and where media-size contains "x" and "y" as collection members.
ii) media-size-supported with two collection values. following sub-sections:
iii) job-notify with notify-recipients and notify-events which is a 5.1.2.1 x-dimension (integer(0:MAX))
1setOf keyword with 3 values in this example
Solution 1a) This attribute identifies the width of the media in inch units
along the X axis.
Name syntax-type value 5.1.2.2 y-dimension (integer(0:MAX))
"media-col" begin-collection ""
"media-col.media-color" keyword white
"media-col.media-size" begin-collection ""
"media-col.media-size.x" integer 850
"media-col.media-size.y" integer 1100
"media-col.media-size" end-collection ""
"media-col" end-collection ""
Name syntax-type value This attribute identifies the height of the media in inch
"media-size-supported" begin-collection "" units along the Y axis.
"media-size-supported.x" integer 850
"media-size-supported.y" integer 1100
"media-size-supported" end-collection ""
"media-size-supported" begin-collection ""
"media-size-supported.x" integer 850
"media-size-supported.y" integer 1400
"media-size-supported" end-collection ""
Name syntax-type value The "media-size-supported" (1setOf collection) Printer
"job-notify" begin-collection "" attribute identifies the values of this "media-size" member
"job-notify.notify-recipients" url "mailto://bill@foo.com" attribute that the Printer supports, i.e., the size
"job-notify.notify-events" keyword job-completed combinations supported. The names of the member attributes
"" keyword job-created are the same as the member attributes of the "media-size"
"" keyword job-state-changed collection attribute, namely "x-dimension", and "y-dimension",
"job-notify" end-collection "" since they have the same attribute syntax and the same
semantics.
Solution 1b) 5.2 media-col-default (collection)
Name syntax-type value The "media-col-default" Printer attribute specifies the media that the
"media-col" begin-collection "" Printer uses, if any, if the client omits the "media-col" and "media".
"media-color-" keyword white Job Template attribute in the Job Creation operation (and the PDL
"media-size-" begin-collection "" doesn't include a media specification). The member attributes are
"x-" integer 850 defined in Table 1. A Printer MUST support the same member attributes
"y-" integer 1100 for this default collection attribute as it supports for the
corresponding "media-col" Job Template attribute.
[Expires: September 9, 2000] 5.3 media-col-ready (1setOf collection)
"media-size-" end-collection ""
"" end-collection ""
Name syntax-type value The "media-col-ready" Printer attribute identifies the media that are
"media-size-supported" begin-collection "" available for use without human intervention, i.e., the media that are
"x-" integer 850 ready to be used without human intervention. The collection value MUST
"y-" integer 1100 have all of the member attributes that are supported in Table 1.
"" end-collection ""
"" begin-collection ""
"x-" integer 850
"y-" integer 1400
"" end-collection ""
Name syntax-type value 5.4 media-col-supported (1setOf type2 keyword)
"job-notify" begin-collection ""
"notify-recipients-" url "mailto://bill@foo.com"
"notify-events-" keyword "job-completed"
"" keyword "job-created"
"" keyword "job-state-changed"
"job-notify" end-collection ""
Solution 2) The "media-col-supported" Printer attribute identifies the keyword names
of the member attributes supported in the "media-col" collection Job
Template attribute, i.e., the keyword names of the member attributes in
Table 1 that the Printer supports.
Name syntax-type value 6 A Second Example Definition Of A Collection Attribute
"media-col" begin-collection ""
"" attribute-name "media-color"
"" keyword white
"" attribute-name "media-size"
"" begin-collection ""
"" attribute-name "x"
"" integer 850
"" attribute-name "y"
"" integer 1100
"" end-collection ""
"" end-collection ""
Name syntax-type value In some printing environments, it is desirable to allow the client to
"media-size-supported" begin-collection "" select the media for the job start sheet. The reason for not adding the
"" attribute-name "x" 'collection' attribute syntax to the existing "job-sheets" Job Template
"" integer 850 attribute is the same as for "media". Instead, a new Job Template
"" attribute-name "y" attribute is introduced, e.g. "job-sheet-col (collection)".
"" integer 1100
"" end-collection ""
"" begin-collection ""
"" attribute-name "x"
"" integer 850
"" attribute-name "y"
"" integer 1400
"" end-collection ""
Name syntax-type value The member attributes of "job-sheet-col" attribute ("job-sheets (type 3
keyword)" and "media (type3 keyword | name)") both follow the naming
rules of item 4a1 of section 3, i.e they reuse existing IPP attributes.
According to the rules, their supported values come from the existing
IPP attributes: "job-sheets-supported" and "media-supported". However,
their default values do not come from "job-sheets-default" and "media-
[Expires: September 9, 2000] default", respectively. Rather the definition of "job-sheet-col" says
"job-notify" begin-collection "" that "job-sheets (type 3 keyword)" is required and if "media (type3
"" attribute-name "notify-recipients" keyword | name)" is absent, the Printer uses the same media as the rest
"" url mailto://bill@foo.com" of the job uses.
"" attribute-name "notify-events"
"" keyword "job-completed"
"" keyword "job-created"
"" keyword "job-state-changed"
"" end-collection ""
Observations: If "job-sheet-col" attribute were defined to contain the member
attribute "job-sheet-media (type3 keyword | name)" instead of "media
(type3 keyword | name)", then the definition would also have to specify
a "job-sheet-media-supported (1setOf (type3 keyword | name))" whose
values would be independent of "media-supported (1setOf (type3 keyword
| name))" and would be set separately by a System Administrator.
Solution 1a have identical properties to solution 1b except that the The actual text for the definition of the attribute is left as an
rules for encoding the name are more complicated for 1a, and the name of exercise for the reader.
the attribute appears before each end-collection and end-collection in
1a but only before the first begin-collection in 1b.
If a collection aware client sends a collection to a collection unaware 7 Encoding
Printer:
For solutions 1a and 1b) the Printer sees many attributes in place of This section defines the additional encoding tags used according to
the collection and it returns in the Unsupported attribute group, all of [ipp-pro] and gives an example of their use.
the attributes: the attribute outside the collection and each attribute
in the collection with it altered name. Thus the unsupported attributes
have names that the client didn't send and they may be in an order that
makes it hard to reconstruct the collection. In addition, because the
"end-collection" has the same name as the attribute for 1a, some
printers will reject the job because the attribute appears twice. Also,
1a does not work for a 1setOf collection because the name of the
attributes appear in front of each begin-collection and thus cannot be
distinguished from two occurrences of the same attribute.
For solution 2) the Printer sees the collection as a 1setOf values where 7.1 Additional tags defined for representing a collection attribute
some values have unknown syntax types and other values have known syntax value
types. When a collection-unaware printer discovers it doesn't
understand an attribute that is a collection, it sees the unknown
attribute as a 1setOf rather than a collection. It still returns the
attribute-name with the out-of-band value "unsupported" making it easier
for the client.
7.1 encoding of a collection (using solution 1a) The 'collection' attribute syntax uses the tags defined in Table 3.
NOTE: If we pick another solution to the encoding, this section will Table 3 - Tags defined for encoding the 'collection' attribute syntax
change.
Each collection MUST have a globally unique name. Each attribute in an Tag name Tag Meaning
attribute group or a collection MUST have globally unique name. value
[Expires: September 9, 2000] begCollection 0x34 Begin the collection attribute value.
Uniqueness is generated by prepending the collection name to the endCollection 0x37 End the collection attribute value.
attribute using a period, '.' as a separator.
For encoding attributes that have a 'collection' attribute syntax, the memberAttrName 0x4A The value is the name of the
attribute's name is REQUIRED to be the first part of each of the member collection member attribute
attribute name separated by a PERIOD (.) character. For example, if a
"media-col" (collection) Job Template attribute is added to IPP and
contains a member attribute "color, it MUST be encoded as a "media-
col.color". In another example, if the "job-sheets" (collection) Job
Template attribute is added to IPP and reuses the "color" member
attribute, the "color" attribute MUST be encoded as "job-sheets.color".
The "xxx.color" attribute has an identical attribute syntax and similar
semantics.
When encoding a collection attribute "xxx" that contains an attribute When encoding a collection attribute "xxx" that contains an attribute
"aaa". A simplified example of a collection specification is given in "aaa" and is not inside another collection, the encoding follows these
section 6 rules:
1.The beginning of the collection is indicated with a value tag that 1.The beginning of the collection is indicated with a value tag that
MUST be syntax type 'begincollection' (e.g. 0x34). MUST be syntax type 'begCollection' (0x34) with a name length and
Name field that represent the name of the collection attribute
2.The length of the collection name (e.g. 0x03) ("xxx") as with any attribute, followed by a value. The Printer MAY
ignore the value and its length of MAY be 0. In the future, however,
3.The collection name (e.g. "xxx") this field MAY contain useful information, such as the collection
name (cf. the name of a C struct).
4.A null collection value length (e.g. 0x00)
5.The attributes are encoded as with any other attribute. It is valid 2. Each member attribute is encoded as a sequence of two or more values
to have a collection a member of a collection. The modifications that appear to be part of a single multi-valued attribute, i.e.
necessary for encoding member attributes of a collection are as 1setOf. The first value after the 'begCollection' value has the
follows. attribute syntax 'memberAttrName' (0x4A) and its value holds the
name of the first member attribute (e.g. "aaa"). The second value
holds the first member's attribute value, which can be of any
attribute syntax, except 'memberAttrName' or 'endCollection'. If the
first member's attribute value is multi-valued, the third value
holds the second value of the first member's value. Otherwise, the
third value holds the name of second member attribute (e.g. "bbb")
and its attribute syntax is 'memberAttrName'. In this case, the
fourth member's value is the value of "bbb".
a) The name of the member attribute MUST be prepended with the Note that the technique of encoding a 'collection' as a '1setOf'
collection name and a period. makes it easy for a Printer that doesn't support a particular
collection attribute (or the collection attribute syntax at all) to
simply skip over the entire collection value.
b) The length of the member attribute name MUST be adjusted 3. The end of the collection is indicated with a value tag that MUST be
appropriately. syntax type 'endCollection' (e.g. 0x37) and MAY have a zero name
length and a zero value length. In the future, this field MAY
contain useful information,such as the collection name that matches
the one in the 'begCollection' .
6.The end of the collection is indicated with a value tag that MUST be 4. It is valid to have a member attribute that is, itself, a collection
syntax type 'endCollection' (e.g. 0x37). attribute, i.e., collections can be nested within collections. This
is represented by the occurrence of a member attribute that is of
attribute syntax type 'begCollection'. Such a collection is
terminated by a matching 'endCollection'. The name of such a member
attribute is in the immediately preceding value whose syntax type is
'memberAttrName'.
7.The length of the collection name (e.g. 0x03) 5. It is valid for a collection attribute to be multi-valued, i.e.,
have more than one collection value. If the next attribute
immediately following the 'endCollection' has a zero name length and
a tag of 'begCollection', then the collection attribute is a multi-
valued collection, as with any attribute. This statement applies to
collections within collections and collections that are not in
collections.
8.The collection name (e.g. "xxx") 7.2 Example encoding: "media-col" (collection)
9.A null collection value length (e.g. 0x00) The collection specified in section 5is used for the encoding example
shown in Table 5. The example also shows nested collections, since the
"media-size" member attribute is a 'collection. The encoding example
represents a blue 4x6-index cards and takes 216 octets. The Appendices
contains more complex examples.
[Expires: September 9, 2000] Additional examples have been included in the appendices.
7.2 Sample Encoding (using solution 1a) The overall structure of the two collection values can be pictorially
represented as:
NOTE: If we pick another solution to the encoding, this section will "media-col" =
change. { "media-color" = 'blue';
"media-size" =
{ "x-dimension" = 6;
"y-dimension" = 4
}
},
This section defines the encoding of a collection syntax type using The full encoding is in table 4. A simplified view of the encoding
solution 1a. The collection specified in section 6 is used. The looks like this:
encoding is of an implementation that does not support any optional
attributes. A collection is encoded by using two new tags:
Tag name Tag Meaning Table 4 - Overview Encoding of "media-col" collection
value
beginCollection 0x34 Begin the named collection. Tag Value Name Value
endCollection 0x37 End the named collection. begCollection media-col ""
memberAttrName "" media-color
keyword "" blue
memberAttrName "" media-size
begCollection "" ""
memberAttrName "" x-dimension
integer "" 6
memberAttrName "" y-dimension
integer "" 4
endCollection "" ""
endCollection "" ""
A collection value is encoded as a sequence of attribute values Table 5 - Example Encoding of "media-col" collection
preceded by a beginCollection attribute and followed by an endCollection
attribute. The name field of a beginCollection and an endCollection both
contain the name of the collection type, i.e., the keyword name of the
collection attribute, which is a string of ASCII characters. The value
field contains the prefix used for all subordinate member attributes.
The following example is written in the style of the IPP/1.1 "Encoding
and Transport" document [ipp-pro]. The following example is for a media
collection attribute. The media collection contains 2 member
attributes. One member is "color" that contains a keyword for the
media's color. The second attribute is a collection that gives the
media's size. The size collection has two integer attributes "x" and
"y" that gives the media's size in inches
Octets Symbolic Protocol comments Octets Symbolic Protocol comments
Value field Value field
0x34 beginCollecti value-tag Beginning of the collection 0x34 begCollection value-tag beginning of the "media-
on col" collection attribute
0x0009 name- Length of collection's name 0x0009 name- length of (collection)
length length attribute name
media-col media-col Name Collection's name media-col media-col name name of (collection)
0x0000 Value- attribute
length 0x0000 value- defined to be 0 for this
length type
no value (since value-
length was 0)
0x44 keyword type value-tag Member attribute type 0x4A memberAttrNam value-tag starts a new member
0x000F name- Length of member attribute e attribute: "media-color"
length name
media-col.color media- Name Name of member attribute
col.color
0x0004 value-
length
blue blue Value
0x34 beginCollecti value-tag Beginning of the sub- 0x0000 name- defined to be 0 for this
on collection length type, so part of 1setOf
no name (since name-length
was 0)
0x000B value- length of "media-color"
length keyword
st
media-color media-color value value is name of 1 member
attribute
[Expires: September 9, 2000] 0x44 keyword type value-tag keyword type
Octets Symbolic Protocol comments Octets Symbolic Protocol comments
Value field Value field
0x000E name- Length of sub-collection's 0x0000 name- 0 indicates 1setOf
length name
media-col.size media- Name Sub-collection's name
col.size
0x0000 Value-
length length
no name (since name-length
0x21 integer type value-tag Member attribute type was 0)
0x0010 name- Length of member attribute
length name
media- media- Name Name of member attribute
col.size.x col.size.x
0x0004 value- 0x0004 value-
length length
0x0006 Value st
blue blue value value of 1 member
attribute
0x21 integer type value-tag Member attribute type 0x4A memberAttrNam value-tag starts a new member
0x0007 name- Length of member attribute e attribute: "media-size"
length name
media- media- Name Name of member attribute
col.size.y col.size.y
0x0004 value-
length
0x0004 Value
0x37 endCollection value-tag end of the sub-collection 0x0000 name- defined to be 0 for this
0x0007 name- Length of sub-collection's length type, so part of 1setOf
length name no name (since name-length
media-col.size media- Name Sub-collection's name was 0)
col.size 0x000A value- length of "media-size"
0x0000 Value- length keyword
length nd
media-size media-size value Name of 2 member
attribute
0x37 endCollection value-tag end of the collection 0x34 begCollection value-tag Beginning of the "media-
0x0007 name- Length of collection's name size" collection attribute
length which is a sub-collection
media-col media-col Name Sub-collection's name 0x0000 name- 0 indicates 1setOf
0x0000 Value-
length length
no name (since name-length
was 0)
0x0000 value- collection attribute names
length have no value
no value (since value-
length was 0)
7.3 1setOf Collection encoding (using solution 1a) 0x4A memberAttrNam value-tag starts a new member
e attribute: "x-dimension"
The encoding of a set of collections follows the standard method of
encoding multi-valued IPP attributes. The "beginCollection" attribute
is coded normally. The first instance of the collection follows. The
"endCollection" MUST appear only once in a collection and MUST follow
the last member of the set of collection. The member collections of a
[Expires: September 9, 2000]
set of collections are delineated by a specially encoded
"beginCollection" attribute. The type MUST be "beginCollection" (i.e.
0x34). The length of the name field MUST be 0x0000. The name field
MUST be omitted. The length of the value MUST be the length of the
collection's prefix. The value MUST be the prefix.
7.4 Sample 1setOf Collection encoding (using solution 1a)
NOTE: If we pick another solution to the encoding, this section will
change.
This section defines the encoding of a collection syntax type using
solution 1a. The collection specified in section 7 is used. The
difference is that the type of "media-col" is 1setOf collection instead
of collection. The encoding is of an implementation that does not
support any optional attributes.
Octets Symbolic Protocol comments
Value field
0x34 beginCollecti value-tag Beginning of the collection 0x0000 name- defined to be 0 for this
on length type, so part of 1setOf
0x0009 name- Length of collection's name no name (since name-length
length was 0)
media-col media-col Name Collection's name 0x000B value- length of "x-dimension"
0x0000 Value- length keyword
length st
x-dimension x-dimension value name of 1 sub-collection
member attribute
0x44 keyword type value-tag Member attribute type 0x21 integer type value-tag attribute type
0x000F name- Length of member attribute 0x0000 name- 0 indicates 1setOf
length name
media-col.color media- Name Name of member attribute
col.color
0x0004 value-
length length
blue blue Value no name (since name-length
was 0)
0x34 beginCollecti value-tag Beginning of the sub- 0x0004 value- length of an integer = 4
on collection
0x000E name- Length of sub-collection's
length name
media-col.size media- Name Sub-collection's name
col.size
0x0000 Value-
length length
0x21 integer type value-tag Member attribute type
0x00010 name- Length of member attribute
length name
[Expires: September 9, 2000]
Octets Symbolic Protocol comments Octets Symbolic Protocol comments
Value field Value field
media- media- Name Name of member attribute st
col.size.y col.size.y 0x0006 value value of 1 sub-
0x0004 value- collection member attribute
length
0x0006 Value
0x21 integer type value-tag Member attribute type
0x00010 name- Length of member attribute
length name
media- media- Name Name of member attribute
col.size.x col.size.x
0x0004 value-
length
0x0004 Value
0x37 endCollection value-tag end of the sub-collection
0x000E name- Length of sub-collection's
length name
media-col.size media- Name Sub-collection's name
col.size
0x0000 Value-
length
Second collection in set
0x34 beginCollecti value-tag Beginning of the collection
on
0x0000 name- Indicates continuation of
length set
0x0000 Value-
length
0x44 keyword type value-tag Member attribute type
0x000F name- Length of member attribute
length name
media-col.color media- Name Name of member attribute
col.color
0x0003 value-
length
red red Value
0x34 beginCollecti value-tag Beginning of the sub-
on collection
0x000E name- Length of sub-collection's
length name
media-col.size media- Name Sub-collection's name
col.size
[Expires: September 9, 2000]
Octets Symbolic Protocol comments 0x4A memberAttrNam value-tag starts a new member
Value field e attribute: "y-dimension"
0x0000 Value- 0x0000 name- defined to be 0 for this
length length type, so part of 1setOf
no name (since name-length
was 0)
0x000B value- length of the "y-dimension"
length keyword
nd
y-dimension y-dimension value name of 2 sub-collection
member attribute
0x21 integer type value-tag Member attribute type 0x21 integer type value-tag attribute type
0x0010 name- Length of member attribute 0x0000 name- 0 indicates 1setOf
length name
media- media- Name Name of member attribute
col.size.y col.size.y
0x0004 value-
length length
0x0006 Value no name (since name-length
was 0)
0x21 integer type value-tag Member attribute type 0x0004 value- length of an integer = 4
0x0010 name- Length of member attribute
length name
media- media- Name Name of member attribute
col.size.x col.size.x
0x0004 value-
length length
0x0004 Value nd
0x0004 value value of 2 sub-
collection member attribute
0x37 endCollection value-tag end of the sub-collection 0x37 endCollection value-tag end of the sub-collection
0x000E name- Length of sub-collection's 0x0000 name- defined to be 0 for this
length name length type, so part of 1setOf
media-col.size media- Name Sub-collection's name no name (since name-length
col.size was 0)
0x0000 Value- 0x0000 value- defined to be 0 for this
length length type
no value (since value-
0x37 endCollection value-tag end of the set of length was 0)
collections 0x37 endCollection value-tag end of the 1st collection
0x0009 name- Length of collection's name value in 1setOf
length 0x0000 name- defined to be 0 for this
media-col media-col Name collection's name length type, so part of 1setOf
0x0000 Value- Length of collection's no name (since name-length
length prefix was 0)
0x0000 value- defined to be 0 for this
length type
no value (since value-
length was 0)
8 Legacy issues 8 Legacy issues
IPP 1.x Printers and Clients will gracefully ignore collections and its IPP 1.x Printers and Clients will gracefully ignore collections and its
member attributes if it does not understand the collection. The 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
will look like ordinary attributes, but since they each are encoded with and their values will look like a 1setOf values of the collection
attribute, so that the Printer simply ignores the entire attribute and
[Expires: September 9, 2000] all of its values. Returning unsupported attributes is also simple,
since only the name of the collection attribute is returned with the
a unique name that can't be the same as a top level attribute, each of 'unsupported' out-of-band value (see section 4.2).
the member attributes will also look like attributes that the recipient
doesn't support and so should ignore.
9 IANA Considerations 9 IANA Considerations
This attribute syntax will be registered with IANA after the WG approves This attribute syntax will be registered with IANA after the WG approves
its specification according to the procedures for extension of the its specification according to the procedures for extension of the
IPP/1.1 Model and Semantics [ipp-mod]. IPP/1.1 Model and Semantics [ipp-mod].
ISSUE 04 - Since this is intended to be a standards track document, do
we also register the attribute syntax with IANA?
10 Internationalization Considerations 10 Internationalization Considerations
This attribute syntax by itself has no impact on internationalization. This attribute syntax by itself has no impact on internationalization.
However, the member attributes that are subsequently defined for use in However, the member attributes that are subsequently defined for use in
a collection may have internationalization considerations, as may any a collection may have internationalization considerations, as may any
attribute, according to [ipp-mod]. attribute, according to [ipp-mod].
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
skipping to change at page 25, line 5 skipping to change at page 19, line 5
[ipp-pro] [ipp-pro]
Herriot, R., Butler, S., Moore, P., Turner, R., "Internet Printing Herriot, R., Butler, S., Moore, P., Turner, R., "Internet Printing
Protocol/1.1: Encoding and Transport", draft-ietf-ipp-protocol-v11- Protocol/1.1: Encoding and Transport", draft-ietf-ipp-protocol-v11-
05.txt, March 1, 2000. 05.txt, March 1, 2000.
[RFC2565] [RFC2565]
Herriot, R., Butler, S., Moore, P., Tuner, R., "Internet Printing Herriot, R., Butler, S., Moore, P., Tuner, R., "Internet Printing
Protocol/1.0: Encoding and Transport", RFC 2565, April 1999. Protocol/1.0: Encoding and Transport", RFC 2565, April 1999.
[Expires: September 9, 2000]
[RFC2566] [RFC2566]
R. deBry, T. Hastings, R. Herriot, S. Isaacson, P. Powell, R. deBry, T. Hastings, R. Herriot, S. Isaacson, P. Powell,
"Internet Printing Protocol/1.0: Model and Semantics", RFC 2566, "Internet Printing Protocol/1.0: Model and Semantics", RFC 2566,
April 1999. April 1999.
[RFC2567] [RFC2567]
Wright, D., "Design Goals for an Internet Printing Protocol", RFC Wright, D., "Design Goals for an Internet Printing Protocol", RFC
2567, April 1999. 2567, April 1999.
[RFC2568] [RFC2568]
skipping to change at page 26, line 4 skipping to change at page 19, line 56
Palo Alto, CA 94304 Palo Alto, CA 94304
Phone: 650-813-7696 Phone: 650-813-7696
Fax: 650-813-6860 Fax: 650-813-6860
e-mail: robert.herriot@pahv.xerox.com e-mail: robert.herriot@pahv.xerox.com
Kirk Ocke Kirk Ocke
Xerox Corp. Xerox Corp.
800 Phillips Rd 800 Phillips Rd
M/S 139-05A M/S 139-05A
Webster, NY 14580 Webster, NY 14580
[Expires: September 9, 2000]
Phone: (716) 442-4832 Phone: (716) 442-4832
EMail: kirk.ocke@usa.xerox.com EMail: kirk.ocke@usa.xerox.com
Peter Zehler Peter Zehler
Xerox Corp. Xerox Corp.
800 Phillips Rd 800 Phillips Rd
M/S 139-05A M/S 139-05A
Webster, NY 14580 Webster, NY 14580
Phone: (716) 265-8755 Phone: (716) 265-8755
EMail: peter.zehler@usa.xerox.com EMail: peter.zehler@usa.xerox.com
14 Appendix A: Full Copyright Statement 14 Appendix A: Encoding Example of a Simple Collection
The overall structure of the collection value can be pictorially
represented as:
" media-size " =
{ "x-dimension" = 6;
"y-dimension" = 4
}
A simplified view of the encoding would look like this:
Table 6 - Overview Encoding of simple collection
Tag Value Name Value
begCollection media-size ""
memberAttrName "" x-dimension
integer "" 6
memberAttrName "" y-dimension
integer "" 4
endCollection "" ""
Note: "" represents a name or value whose length is 0.
Table 7 - Example Encoding of simple collection
Octets Symbolic Protocol comments
Value field
0x34 begCollection value-tag beginning of the "media-
size" collection attribute
0x000A name- length of (collection)
length attribute name
media-size media-size name name of (collection)
attribute
0x0000 value- defined to be 0 for this
length type
no value (since value-
length was 0)
0x4A memberAttrNam value-tag starts member attribute:
e "x-dimension"
0x0000 name- defined to be 0 for this
length type, so part of 1setOf
no name (since name-length
was 0)
0x000B value- length of "x-dimension"
length keyword
st
x-dimension x-dimension value name of 1 collection
member attribute
0x21 integer type value-tag attribute type
0x0000 name- 0 indicates 1setOf
length
no name (since name-length
was 0)
0x0004 value- length of an integer = 4
length
st
0x0006 value value of 1 collection
member attribute
Octets Symbolic Protocol comments
Value field
0x4A memberAttrNam value-tag starts a new member
e attribute: "y-dimension"
0x0000 name- defined to be 0 for this
length type, so part of 1setOf
no name (since name-length
was 0)
0x000B value- length of the "y-dimension"
length keyword
nd
y-dimension y-dimension value name of 2 collection
member attribute
0x21 integer type value-tag attribute type
0x0000 name- 0 indicates 1setOf for
length media-size
no name (since name-length
was 0)
0x0004 value- length of an integer = 4
length
nd
0x0004 value value of 2 collection
member attribute
0x37 endCollection value-tag end of the collection
0x0000 name- defined to be 0 for this
length type, so part of 1setOf
no name (since name-length
was 0)
0x0000 value- defined to be 0 for this
length type
no value (since value-
length was 0)
15 Appendix B: Encoding Example of 1setOf Collection
The overall structure of the collection value can be pictorially
represented as:
"media-size-supported" =
{ "x-dimension" = 6;
"y-dimension" = 4
},
{ "x-dimension" = 3;
"y-dimension" = 5
};
A simplified view of the encoding would look like this:
Table 8 - Overview Encoding of 1setOf collection
Tag Value Name Value
begCollection media-size-supported ""
memberAttrName "" x-dimension
integer "" 6
memberAttrName "" y-dimension
integer "" 4
endCollection "" ""
begCollection "" ""
memberAttrName "" x-dimension
integer "" 3
memberAttrName "" y-dimension
integer "" 5
endCollection "" ""
Table 9 - Example Encoding of 1setOf collection
Octets Symbolic Protocol comments
Value field
0x34 begCollection value-tag beginning of the "media-
size-supported (1setOf
collection" attribute
0x00014 name- length of (collection)
length attribute name
media-size- media-size- name name of (collection)
supported supported attribute
0x0000 value- defined to be 0 for this
length type
no value (since value-
length was 0)
0x4A memberAttrNam value-tag starts member attribute:
e "x-dimension"
0x0000 name- defined to be 0 for this
length type, so part of 1setOf
no name (since name-length
was 0)
0x000B value- length of "x-dimension"
length keyword
st
x-dimension x-dimension value name of 1 collection
member attribute
0x21 integer type value-tag attribute type
0x0000 name- 0 indicates 1setOf
length
no name (since name-length
was 0)
Octets Symbolic Protocol comments
Value field
0x0004 value- length of an integer = 4
length
st
0x0006 value value of 1 collection
member attribute
0x4A memberAttrNam value-tag starts member attribute:
e "y-dimension"
0x0000 name- defined to be 0 for this
length type, so part of 1setOf
no name (since name-length
was 0)
0x000B value- length of the "y-dimension"
length keyword
nd
y-dimension y-dimension value name of 2 collection
member attribute
0x21 integer type value-tag attribute type
0x0000 name- 0 indicates 1setOf
length
no name (since name-length
was 0)
0x0004 value- length of an integer = 4
length
nd
0x0004 value value of 2 collection
member attribute
0x37 endCollection value-tag end of the collection
0x0000 name- defined to be 0 for this
length type, so part of 1setOf
no name (since name-length
was 0)
0x0000 value- defined to be 0 for this
length type
no value (since value-
length was 0)
nd
0x34 begCollection value-tag beginning of the 2 member
of the 1SetOf "sizes-avail
" collection attribute
0x0000 name- Zero length name indicates
length this is member of previous
attribute
name no name (since name-length
was 0)
0x0000 value- defined to be 0 for this
length type
no value (since value-
length was 0)
0x4A memberAttrNam value-tag starts member attribute:
e "x-dimension"
0x0000 name- defined to be 0 for this
length type, so part of 1setOf
Octets Symbolic Protocol comments
Value field
no name (since name-length
was 0)
0x000B value- length of "x-dimension"
length keyword
st
x-dimension x-dimension value name of 1 collection
member attribute
0x21 integer type value-tag attribute type
0x0000 name- 0 indicates 1setOf
length
no name (since name-length
was 0)
0x0004 value- length of an integer = 4
length
st
0x0003 value value of 1 collection
member attribute
0x4A memberAttrNam value-tag starts member attribute:
e "y-dimension"
0x0000 name- defined to be 0 for this
length type, so part of 1setOf
no name (since name-length
was 0)
0x000B value- length of the "y-dimension"
length keyword
nd
y-dimension y-dimension value name of 2 collection
member attribute
0x21 integer type value-tag attribute type
0x0000 name- 0 indicates 1setOf
length
no name (since name-length
was 0)
0x0004 value- length of an integer = 4
length
nd
0x0005 value value of 2 collection
member attribute
0x37 endCollection value-tag end of the 1setOf
collection value
0x0000 name- defined to be 0 for this
length type, so part of 1setOf
no name (since name-length
was 0)
0x0000 value- defined to be 0 for this
length type
no value (since value-
length was 0)
16 Appendix C: Encoding Example of Collection containing 1setOf XXX
attribute
The overall structure of the collection value can be pictorially
represented as:
"wagons" =
{ "colors" = red, blue;
"sizes" = 4, 6, 8
}
A simplified view of the encoding would look like this:
Table 10 - Overview Encoding of collection with 1setOf value
Tag Value Name Value
begCollection wagons ""
memberAttrName "" colors
keyword "" red
keyword "" blue
memberAttrName "" sizes
integer "" 4
integer "" 6
integer "" 8
endCollection "" ""
Table 11 - Example Encoding of collection with 1setOf value
Octets Symbolic Protocol comments
Value field
0x34 begCollection value-tag beginning of the "wagons"
collection attribute
0x0005 name- length of (collection)
length attribute name
wagons wagons name name of (collection)
attribute
0x0000 value- defined to be 0 for this
length type
no value (since value-
length was 0)
0x4A memberAttrNam value-tag starts a new member
e attribute: "colors"
0x0000 name- defined to be 0 for this
length type, so part of 1setOf
no name (since name-length
was 0)
0x0006 value- length of "colors" keyword
length
Octets Symbolic Protocol comments
Value field
st
colors colosr value value is name of 1 member
attribute
0x44 keyword type value-tag keyword type
0x0000 name- 0 indicates 1setOf wagons
length
no name (since name-length
was 0)
0x0004 value-
length
st
blue blue value value of 1 member
attribute
0x44 keyword type value-tag keyword type
0x0000 name- 0 indicates 1setOf wagons
length
no name (since name-length
was 0)
0x0003 value-
length
st
red red value value of 1 member
attribute
0x4A memberAttrNam value-tag starts a new member
e attribute: "sizes"
0x0000 name- defined to be 0 for this
length type, so part of 1setOf
no name (since name-length
was 0)
0x0005 value- length of "length-avail"
length keyword
nd
sizes sizes value Name of 2 member
attribute
0x21 integer type value-tag attribute type
0x0000 name- 0 indicates 1setOf wagons
length
no name (since name-length
was 0)
0x0004 value- length of an integer = 4
length
st
0x0004 value 1 value for 1SetOf
integer attribute
0x21 integer type value-tag attribute type
0x0000 name- 0 indicates 1setOf
length
Octets Symbolic Protocol comments
Value field
no name (since name-length
was 0)
0x0004 value- length of an integer = 4
length
nd
0x0006 value 2 value for 1SetOf
integer attribute
0x21 integer type value-tag attribute type
0x0000 name- 0 indicates 1setOf
length
no name (since name-length
was 0)
0x0004 value- length of an integer = 4
length
rd
0x0008 value 3 value for 1SetOf
integer attribute
0x37 endCollection value-tag end of the collection
0x0000 name- defined to be 0 for this
length type, so part of 1setOf
no name (since name-length
was 0)
0x0000 value- defined to be 0 for this
length type
no value (since value-
length was 0)
17 Appendix D: Full Copyright Statement
Copyright (C) The Internet Society (1998,1999,2000). All Rights Reserved Copyright (C) The Internet Society (1998,1999,2000). 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 or others, and derivative works that comment on or otherwise explain it or
assist in its implementation may be prepared, copied, published and assist in its implementation may be prepared, copied, published and
distributed, in whole or in part, without restriction of any kind, distributed, in whole or in part, without restriction of any kind,
provided that the above copyright notice and this paragraph are included provided that the above copyright notice and this paragraph are included
on all such copies and derivative works. However, this document itself on all such copies and derivative works. However, this document itself
may not be modified in any way, such as by removing the copyright notice may not be modified in any way, such as by removing the copyright notice
skipping to change at line 1319 skipping to change at line 1401
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 "AS This document and the information contained herein is provided on an "AS
IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK
FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT
LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT
INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR
FITNESS FOR A PARTICULAR PURPOSE. FITNESS FOR A PARTICULAR PURPOSE.
[Expires: September 9, 2000]
 End of changes. 

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