Internet DRAFT - draft-sweet-rfc2910bis
draft-sweet-rfc2910bis
IPP WG M. Sweet
Internet-Draft Apple Inc.
Obsoletes: 2910,3382 (if approved) I. McDonald
Intended status: Standards Track High North, Inc.
Expires: June 17, 2016 December 15, 2015
Internet Printing Protocol/1.1: Encoding and Transport
draft-sweet-rfc2910bis-07
Abstract
This document is one of a set of documents, which together describe
all aspects of a new Internet Printing Protocol (IPP). IPP is an
application level protocol that can be used for distributed printing
using Internet tools and technologies. This document defines the
rules for encoding IPP operations and IPP attributes into the
Internet MIME media type called "application/ipp". This document
also defines the rules for transporting a message body whose Content-
Type is "application/ipp" over HTTP.
Editor's Note
This draft is being submitted as an AD-sponsored replacement of RFCs
2910 and 3382, with drafts being reviewed and edited by the IEEE-
ISTO's Printer Working Group IPP WG. The initial goal is to have an
clean version of IPP/1.1 as an IETF Proposed Standard. The long-term
goal is to advance IPP/1.1 to IETF Internet Standard.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on June 17, 2016.
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Copyright Notice
Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions Used in This Document . . . . . . . . . . . . . . 4
2.1. Requirements Language . . . . . . . . . . . . . . . . . . . 4
2.2. Printing Terminology . . . . . . . . . . . . . . . . . . . 4
2.3. Abbreviations . . . . . . . . . . . . . . . . . . . . . . . 5
3. Encoding of the Operation Layer . . . . . . . . . . . . . . . 6
3.1. Picture of the Encoding . . . . . . . . . . . . . . . . . . 7
3.1.1. Request and Response . . . . . . . . . . . . . . . . . . 7
3.1.2. Attribute Group . . . . . . . . . . . . . . . . . . . . . 8
3.1.3. Attribute . . . . . . . . . . . . . . . . . . . . . . . . 8
3.1.4. Attribute-with-one-value . . . . . . . . . . . . . . . . 8
3.1.5. Additional-value . . . . . . . . . . . . . . . . . . . . 9
3.1.6. Collection Attribute . . . . . . . . . . . . . . . . . . 10
3.1.7. Member Attributes . . . . . . . . . . . . . . . . . . . . 11
3.1.8. Alternative Picture of the Encoding of a Request Or a
Response . . . . . . . . . . . . . . . . . . . . . . . . 12
3.2. Syntax of Encoding . . . . . . . . . . . . . . . . . . . . 13
3.3. Attribute-group . . . . . . . . . . . . . . . . . . . . . . 15
3.4. Required Parameters . . . . . . . . . . . . . . . . . . . . 17
3.4.1. Version-number . . . . . . . . . . . . . . . . . . . . . 17
3.4.2. Operation-id . . . . . . . . . . . . . . . . . . . . . . 17
3.4.3. Status-code . . . . . . . . . . . . . . . . . . . . . . . 17
3.4.4. Request-id . . . . . . . . . . . . . . . . . . . . . . . 18
3.5. Tags . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
3.5.1. Delimiter Tags . . . . . . . . . . . . . . . . . . . . . 18
3.5.2. Value Tags . . . . . . . . . . . . . . . . . . . . . . . 19
3.6. Name-Length . . . . . . . . . . . . . . . . . . . . . . . . 21
3.7. (Attribute) Name . . . . . . . . . . . . . . . . . . . . . 22
3.8. Value Length . . . . . . . . . . . . . . . . . . . . . . . 22
3.9. (Attribute) Value . . . . . . . . . . . . . . . . . . . . . 22
3.10. Data . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
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4. Encoding of Transport Layer . . . . . . . . . . . . . . . . . 24
4.1. Printer URI, Job URI, and Job ID . . . . . . . . . . . . . 25
5. IPP URI Schemes . . . . . . . . . . . . . . . . . . . . . . . 26
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 28
7. Internationalization Considerations . . . . . . . . . . . . . 28
8. Security Considerations . . . . . . . . . . . . . . . . . . . 28
8.1. Security Conformance Requirements . . . . . . . . . . . . . 28
8.1.1. Digest Authentication . . . . . . . . . . . . . . . . . . 29
8.1.2. Transport Layer Security (TLS) . . . . . . . . . . . . . 29
8.2. Using IPP with TLS . . . . . . . . . . . . . . . . . . . . 30
9. Interoperability with Other IPP Versions . . . . . . . . . . 30
9.1. The "version-number" Parameter . . . . . . . . . . . . . . 30
9.2. Security and URI Schemes . . . . . . . . . . . . . . . . . 31
10. Changes Since RFC 2910 . . . . . . . . . . . . . . . . . . . 31
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 32
11.1. Normative References . . . . . . . . . . . . . . . . . . . 32
11.2. Informative References . . . . . . . . . . . . . . . . . . 34
Appendix A. Protocol Examples . . . . . . . . . . . . . . . . . 34
A.1. Print-Job Request . . . . . . . . . . . . . . . . . . . . . 34
A.2. Print-Job Response (successful) . . . . . . . . . . . . . . 36
A.3. Print-Job Response (failure) . . . . . . . . . . . . . . . 38
A.4. Print-Job Response (success with attributes ignored) . . . 39
A.5. Print-URI Request . . . . . . . . . . . . . . . . . . . . . 41
A.6. Create-Job Request . . . . . . . . . . . . . . . . . . . . 43
A.7. Create-Job Request with Collection Attributes . . . . . . . 43
A.8. Get-Jobs Request . . . . . . . . . . . . . . . . . . . . . 45
A.9. Get-Jobs Response . . . . . . . . . . . . . . . . . . . . . 47
Appendix B. Registration of MIME Media Type Information for
"application/ipp" . . . . . . . . . . . . . . . . . 48
Appendix C. Acknowledgements . . . . . . . . . . . . . . . . . . 49
Appendix D. Change History . . . . . . . . . . . . . . . . . . . 50
D.1. Changes In -07 . . . . . . . . . . . . . . . . . . . . . . 50
D.2. Changes In -06 . . . . . . . . . . . . . . . . . . . . . . 50
D.3. Changes In -05 . . . . . . . . . . . . . . . . . . . . . . 51
D.4. Changes In -04 . . . . . . . . . . . . . . . . . . . . . . 52
D.5. Changes In -03 . . . . . . . . . . . . . . . . . . . . . . 52
D.6. Changes In -02 . . . . . . . . . . . . . . . . . . . . . . 52
D.7. Changes In -01 . . . . . . . . . . . . . . . . . . . . . . 53
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 53
1. Introduction
This document contains the rules for encoding IPP operations and
describes two layers: the transport layer and the operation layer.
The transport layer consists of an HTTP request and response. All
IPP implementations MUST support HTTP/1.1, the relevant parts of
which are described in the following RFCs:
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o Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing
[RFC7230]
o Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content
[RFC7231]
o Hypertext Transfer Protocol (HTTP/1.1): Conditional Requests
[RFC7232]
o Hypertext Transfer Protocol (HTTP/1.1): Caching [RFC7234]
o Hypertext Transfer Protocol (HTTP/1.1): Authentication [RFC7235]
o The 'Basic' HTTP Authentication Scheme [RFC7617]
o HTTP Digest Access Authentication [RFC7616]
IPP implementations MAY support HTTP/2 which is described in the
following RFCs:
o Hypertext Transfer Protocol Version 2 (HTTP/2) [RFC7540]
o HPACK - Header Compression for HTTP/2 [RFC7541]
This document specifies the HTTP headers that an IPP implementation
supports.
The operation layer consists of a message body in an HTTP request or
response. The "Internet Printing Protocol/1.1: Model and Semantics"
[RFC2911bis] and subsequent extensions (collectively known as the IPP
Model) define the semantics of such a message body and the supported
values. This document specifies the encoding of an IPP request and
response message.
2. Conventions Used in This Document
2.1. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
2.2. Printing Terminology
Client: Initiator of outgoing IPP session requests and sender of
outgoing IPP operation requests (Hypertext Transfer Protocol --
HTTP/1.1 [RFC7230] User Agent).
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Document: An object created and managed by a Printer that contains
description, processing, and status information. A Document object
may have attached data and is bound to a single Job.
'ipp' URI: An IPP URI as defined in [RFC3510].
'ipps' URI: An IPPS URI as defined in [RFC7472].
Job: An object created and managed by a Printer that contains
description, processing, and status information. The Job also
contains zero or more Document objects.
Logical Device: A print server, software service, or gateway that
processes Jobs and either forwards or stores the processed Job or
uses one or more Physical Devices to render output.
Model: The semantics of operations, attributes, values, and status
codes used in the Internet Printing Protocol as defined in the
Internet Printing Protocol/1.1: Model and Semantics [RFC2911bis] and
subsequent extensions.
Output Device: A single Logical or Physical Device.
Physical Device: A hardware implementation of an endpoint device,
e.g., a marking engine, a fax modem, etc.
Printer: Listener for incoming IPP session requests and receiver of
incoming IPP operation requests (Hypertext Transfer Protocol --
HTTP/1.1 [RFC7230] Server) that represents one or more Physical
Devices or a Logical Device.
2.3. Abbreviations
ABNF: Augmented Backus-Naur Form [RFC5234]
ASCII: American Standard Code for Information Interchange [ASCII]
HTTP: HyperText Transfer Protocol [RFC7230]
HTTPS: HTTP over TLS [RFC2818]
IANA: Internet Assigned Numbers Authority
IEEE: Institute of Electrical and Electronics Engineers
IESG: Internet Engineering Steering Group
IPP: Internet Printing Protocol (this document and [PWG5100.12])
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ISTO: IEEE Industry Standards and Technology Organization
LPD: Line Printer Daemon Protocol [RFC1179]
PWG: IEEE-ISTO Printer Working Group <http://www.pwg.org/>
RFC: Request for Comments
TCP: Transmission Control Protocol [RFC793]
TLS: Transport Layer Security [RFC5246]
URI: Uniform Resource Identifier [RFC3986]
URL: Uniform Resource Locator [RFC3986]
UTF-8: Unicode Transformation Format - 8-bit [RFC3629]
3. Encoding of the Operation Layer
The operation layer is the message body part of the HTTP request or
response and it MUST contain a single IPP operation request or IPP
operation response. Each request or response consists of a sequence
of values and attribute groups. Attribute groups consist of a
sequence of attributes each of which is a name and value. Names and
values are ultimately sequences of octets.
The encoding consists of octets as the most primitive type. There
are several types built from octets, but three important types are
integers, character strings and octet strings, on which most other
data types are built. Every character string in this encoding MUST
be a sequence of characters where the characters are associated with
some charset and some natural language. A character string MUST be
in "reading order" with the first character in the value (according
to reading order) being the first character in the encoding. A
character string whose associated charset is US-ASCII whose
associated natural language is US English is henceforth called a US-
ASCII-STRING. A character string whose associated charset and
natural language are specified in a request or response as described
in the Model is henceforth called a LOCALIZED-STRING. An octet
string MUST be in "Model order" with the first octet in the value
(according to the Model order) being the first octet in the encoding.
Every integer in this encoding MUST be encoded as a signed integer
using two's-complement binary encoding with big-endian format (also
known as "network order" and "most significant byte first"). The
number of octets for an integer MUST be 1, 2 or 4, depending on usage
in the protocol. Such one-octet integers, henceforth called SIGNED-
BYTE, are used for the version-number and tag fields. Such two-byte
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integers, henceforth called SIGNED-SHORT are used for the operation-
id, status-code and length fields. Four byte integers, henceforth
called SIGNED-INTEGER, are used for value fields and the request-id.
The following two sections present the encoding of the operation
layer in two ways:
o informally through pictures and description
o formally through Augmented Backus-Naur Form (ABNF), as specified
by RFC 5234 [RFC5234]
An operation request or response MUST use the encoding described in
these two sections.
3.1. Picture of the Encoding
3.1.1. Request and Response
An operation request or response is encoded as follows:
-----------------------------------------------
| version-number | 2 bytes - required
-----------------------------------------------
| operation-id (request) |
| or | 2 bytes - required
| status-code (response) |
-----------------------------------------------
| request-id | 4 bytes - required
-----------------------------------------------
| attribute-group | n bytes - 0 or more
-----------------------------------------------
| end-of-attributes-tag | 1 byte - required
-----------------------------------------------
| data | q bytes - optional
-----------------------------------------------
Figure 1: IPP Message Format
The first three fields in the above diagram contain the value of
attributes described in Section 3.1.1 of the Model.
The fourth field is the "attribute-group" field, and it occurs 0 or
more times. Each "attribute-group" field represents a single group
of attributes, such as an Operation Attributes group or a Job
Attributes group (see the Model). The Model specifies the required
attribute groups and their order for each operation request and
response.
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The "end-of-attributes-tag" field is always present, even when the
"data" is not present. The Model specifies whether the "data" field
is present for each operation request and response.
3.1.2. Attribute Group
Each "attribute-group" field is encoded as follows:
-----------------------------------------------
| begin-attribute-group-tag | 1 byte
----------------------------------------------------------
| attribute | p bytes |- 0 or more
----------------------------------------------------------
Figure 2: Attribute Group Encoding
An "attribute-group" field contains zero or more "attribute" fields.
Note, the values of the "begin-attribute-group-tag" field and the
"end-of-attributes-tag" field are called "delimiter-tags".
3.1.3. Attribute
An "attribute" field is encoded as follows:
-----------------------------------------------
| attribute-with-one-value | q bytes
----------------------------------------------------------
| additional-value | r bytes |- 0 or more
----------------------------------------------------------
Figure 3: Attribute Encoding
When an attribute is single valued (e.g. "copies" with value of 10)
or multi-valued with one value (e.g. "sides-supported" with just the
value 'one-sided') it is encoded with just an "attribute-with-one-
value" field. When an attribute is multi-valued with n values (e.g.
"sides-supported" with the values 'one-sided' and 'two-sided-long-
edge'), it is encoded with an "attribute-with-one-value" field
followed by n-1 "additional-value" fields.
3.1.4. Attribute-with-one-value
Each "attribute-with-one-value" field is encoded as follows:
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-----------------------------------------------
| value-tag | 1 byte
-----------------------------------------------
| name-length (value is u) | 2 bytes
-----------------------------------------------
| name | u bytes
-----------------------------------------------
| value-length (value is v) | 2 bytes
-----------------------------------------------
| value | v bytes
-----------------------------------------------
Figure 4: Single Value Attribute Encoding
An "attribute-with-one-value" field is encoded with five subfields:
o The "value-tag" field specifies the attribute syntax, e.g. 0x44
for the attribute syntax 'keyword'.
o The "name-length" field specifies the length of the "name" field
in bytes, e.g. u in the above diagram or 15 for the name "sides-
supported".
o The "name" field contains the textual name of the attribute, e.g.
"sides-supported".
o The "value-length" field specifies the length of the "value" field
in bytes, e.g. v in the above diagram or 9 for the (keyword) value
'one-sided'.
o The "value" field contains the value of the attribute, e.g. the
textual value 'one-sided'.
3.1.5. Additional-value
Each "additional-value" field is encoded as follows:
-----------------------------------------------
| value-tag | 1 byte
-----------------------------------------------
| name-length (value is 0x0000) | 2 bytes
-----------------------------------------------
| value-length (value is w) | 2 bytes
-----------------------------------------------
| value | w bytes
-----------------------------------------------
Figure 5: Additional Attribute Value Encoding
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An "additional-value" is encoded with four subfields:
o The "value-tag" field specifies the attribute syntax, e.g. 0x44
for the attribute syntax 'keyword'.
o The "name-length" field has the value of 0 in order to signify
that it is an "additional-value". The value of the "name-length"
field distinguishes an "additional-value" field ("name-length" is
0) from an "attribute-with-one-value" field ("name-length" is not
0).
o The "value-length" field specifies the length of the "value" field
in bytes, e.g. w in the above diagram or 19 for the (keyword)
value 'two-sided-long-edge'.
o The "value" field contains the value of the attribute, e.g. the
textual value 'two-sided-long-edge'.
3.1.6. Collection Attribute
Collection attributes create a named group containing related
"member" attributes. The "attribute-with-one-value" field for a
collection attribute is encoded as follows:
-----------------------------------------------
| value-tag (value is 0x34) | 1 byte
-----------------------------------------------
| name-length (value is u) | 2 bytes
-----------------------------------------------
| name | u bytes
-----------------------------------------------
| value-length (value is 0x0000) | 2 bytes
-----------------------------------------------------------
| member-attribute | q bytes |-0 or more
-----------------------------------------------------------
| end-value-tag (value is 0x37) | 1 byte
-----------------------------------------------
| end-name-length (value is 0x0000) | 2 bytes
-----------------------------------------------
| end-value-length (value is 0x0000) | 2 bytes
-----------------------------------------------
Figure 6: Collection Attribute Encoding
Collection attribute is encoded with eight subfields:
o The "value-tag" field specifies the start attribute syntax: 0x34
for the attribute syntax 'begCollection'.
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o The "name-length" field specifies the length of the "name" field
in bytes, e.g. u in the above diagram or 9 for the name "media-
col". Additional collection attribute values use a name length of
0x0000.
o The "name" field contains the textual name of the attribute, e.g.
"media-col".
o The "value-length" field specifies a length of 0x0000.
o The "member-attribute" field contains member attributes encoded as
defined in Section 3.1.7.
o The "end-value-tag" field specifies the end attribute syntax: 0x37
for the attribute syntax 'endCollection'.
o The "end-name-length" field specifies a length of 0x0000.
o The "end-value-length" field specifies a length of 0x0000.
3.1.7. Member Attributes
Each "member-attribute" field is encoded as follows:
-----------------------------------------------
| value-tag (value is 0x4A) | 1 byte
-----------------------------------------------
| name-length (value is 0x0000) | 2 bytes
-----------------------------------------------
| value-length (value is w) | 2 bytes
-----------------------------------------------
| value (member-name) | w bytes
-----------------------------------------------
| member-value-tag | 1 byte
-----------------------------------------------
| name-length (value is 0x0000) | 2 bytes
-----------------------------------------------
| member-value-length (value is x) | 2 bytes
-----------------------------------------------
| member-value | x bytes
-----------------------------------------------
Figure 7: Member Attribute Encoding
A "member-attribute" is encoded with eight subfields:
o The "value-tag" field specifies 0x4A for the attribute syntax
'memberAttrName'.
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o The "name-length" field has the value of 0 in order to signify
that it is a "member-attribute" contained in the collection.
o The "value-length" field specifies the length of the "value" field
in bytes, e.g. w in the above diagram or 10 for the member
attribute name 'media-type'. Additional member attribute values
are specifies using a value length of 0.
o The "value" field contains the name of the member attribute, e.g.
the textual value 'media-type'.
o The "member-value-tag" field specifies the attribute syntax for
the member attribute, e.g. 0x44 for the attribute syntax
'keyword'.
o The second "name-length" field has the value of 0 in order to
signify that it is a "member-attribute" contained in the
collection.
o The "member-value-length" field specifies the length of the member
attribute value, e.g. x in the above diagram or 10 for the value
'stationery'.
o The "member-value" field contains the value of the attribute, e.g.
the textual value 'stationery'.
3.1.8. Alternative Picture of the Encoding of a Request Or a Response
From the standpoint of a parser that performs an action based on a
"tag" value, the encoding consists of:
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-----------------------------------------------
| version-number | 2 bytes - required
-----------------------------------------------
| operation-id (request) |
| or | 2 bytes - required
| status-code (response) |
-----------------------------------------------
| request-id | 4 bytes - required
-----------------------------------------------------------
| tag (delimiter-tag or value-tag) | 1 byte |
----------------------------------------------- |-0 or more
| empty or rest of attribute | x bytes |
-----------------------------------------------------------
| end-of-attributes-tag | 1 byte - required
-----------------------------------------------
| data | y bytes - optional
-----------------------------------------------
Figure 8: Encoding Based On Value Tags
The following show what fields the parser would expect after each
type of "tag":
o "begin-attribute-group-tag": expect zero or more "attribute"
fields
o "value-tag": expect the remainder of an "attribute-with-one-value"
or an "additional-value".
o "end-of-attributes-tag": expect that "attribute" fields are
complete and there is optional "data"
3.2. Syntax of Encoding
The ABNF [RFC5234] syntax for an IPP message is shown in Figure 9.
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ipp-message = ipp-request / ipp-response
ipp-request = version-number operation-id request-id
*attribute-group end-of-attributes-tag data
ipp-response = version-number status-code request-id
*attribute-group end-of-attributes-tag data
version-number = major-version-number minor-version-number
major-version-number = SIGNED-BYTE
minor-version-number = SIGNED-BYTE
operation-id = SIGNED-SHORT ; mapping from model
status-code = SIGNED-SHORT ; mapping from model
request-id = SIGNED-INTEGER ; whose value is > 0
attribute-group = begin-attribute-group-tag *attribute
attribute = attribute-with-one-value *additional-value
attribute-with-one-value = value-tag name-length name
value-length value
additional-value = value-tag zero-name-length
value-length value
name-length = SIGNED-SHORT ; number of octets of 'name'
name = LALPHA *( LALPHA / DIGIT / "-" / "_" / "." )
value-length = SIGNED-SHORT ; number of octets of 'value'
value = OCTET-STRING
data = OCTET-STRING
zero-name-length = %x00.00 ; name-length of 0
value-tag = %x10-FF ; see section 3.5.2
begin-attribute-group-tag = %x00-02 / %04-0F ; see section 3.5.1
end-of-attributes-tag = %x03 ; tag of 3
; see section 3.5.1
SIGNED-BYTE = BYTE
SIGNED-SHORT = 2BYTE
SIGNED-INTEGER = 4BYTE
DIGIT = %x30-39 ; "0" to "9"
LALPHA = %x61-7A ; "a" to "z"
BYTE = %x00-FF
OCTET-STRING = *BYTE
Figure 9: ABNF of IPP Message Format
Figure 10 defines additional terms that are referenced in this
document and provides an alternate grouping of the delimiter tags.
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delimiter-tag = begin-attribute-group-tag / ; see section 3.5.1
end-of-attributes-tag
delimiter-tag = %x00-0F ; see section 3.5.1
begin-attribute-group-tag = %x00 / operation-attributes-tag /
job-attributes-tag / printer-attributes-tag /
unsupported-attributes-tag / %x06-0F
operation-attributes-tag = %x01 ; tag of 1
job-attributes-tag = %x02 ; tag of 2
printer-attributes-tag = %x04 ; tag of 4
unsupported-attributes-tag = %x05 ; tag of 5
Figure 10: ABNF for Attribute Group Tags
3.3. Attribute-group
Each "attribute-group" field MUST be encoded with the "begin-
attribute-group-tag" field followed by zero or more "attribute" sub-
fields.
Table 1 maps the Model group name to value of the "begin-attribute-
group-tag" field:
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+----------------+--------------------------------------------------+
| Model Document | "begin-attribute-group-tag" field values |
| Group | |
+----------------+--------------------------------------------------+
| Operation | "operations-attributes-tag" |
| Attributes | |
+----------------+--------------------------------------------------+
| Job Template | "job-attributes-tag" |
| Attributes | |
+----------------+--------------------------------------------------+
| Job Object | "job-attributes-tag" |
| Attributes | |
+----------------+--------------------------------------------------+
| Unsupported | "unsupported-attributes-tag" |
| Attributes | |
+----------------+--------------------------------------------------+
| Requested | (Get-Job-Attributes) "job-attributes-tag" |
| Attributes | |
+----------------+--------------------------------------------------+
| Requested | (Get-Printer-Attributes)"printer-attributes-tag" |
| Attributes | |
+----------------+--------------------------------------------------+
| Document | in a special position as described above |
| Content | |
+----------------+--------------------------------------------------+
Table 1: Group Values
For each operation request and response, the Model prescribes the
required and optional attribute groups, along with their order.
Within each attribute group, the Model prescribes the required and
optional attributes, along with their order.
When the Model requires an attribute group in a request or response
and the attribute group contains zero attributes, a request or
response SHOULD encode the attribute group with the "begin-attribute-
group-tag" field followed by zero "attribute" fields. For example,
if the Client requests a single unsupported attribute with the Get-
Printer-Attributes operation, the Printer MUST return no "attribute"
fields, and it SHOULD return a "begin-attribute-group-tag" field for
the Printer Attributes Group. The Unsupported Attributes group is
not such an example. According to the Model, the Unsupported
Attributes Group SHOULD be present only if the unsupported attributes
group contains at least one attribute.
A receiver of a request MUST be able to process the following as
equivalent empty attribute groups:
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a. A "begin-attribute-group-tag" field with zero following
"attribute" fields.
b. An expected but missing "begin-attribute-group-tag" field.
When the Model requires a sequence of an unknown number of attribute
groups, each of the same type, the encoding MUST contain one "begin-
attribute-group-tag" field for each attribute group even when an
"attribute-group" field contains zero "attribute" sub-fields. For
example, the Get-Jobs operation may return zero attributes for some
jobs and not others. The "begin-attribute-group-tag" field followed
by zero "attribute" fields tells the recipient that there is a Job in
queue for which no information is available except that it is in the
queue.
3.4. Required Parameters
Some operation elements are called parameters in the Model. They
MUST be encoded in a special position and they MUST NOT appear as
operation attributes. These parameters are described in the
subsections below.
3.4.1. Version-number
The "version-number" field consists of a major and minor version-
number, each of which is represented by a SIGNED-BYTE. The major
version-number is the first byte of the encoding and the minor
version-number is the second byte of the encoding. The protocol
described in [RFC2911bis] has a major version-number of 1 (0x01) and
a minor version-number of 1 (0x01). The ABNF for these two bytes is
%x01.01.
Note: See Section 9 for more information on the "version-number"
field and IPP version numbers.
3.4.2. Operation-id
The "operation-id" field contains an operation-id value as defined in
the Model. The value is encoded as a SIGNED-SHORT and is located in
the third and fourth bytes of the encoding of an operation request.
3.4.3. Status-code
The "status-code" field contains a status-code value as defined in
the Model. The value is encoded as a SIGNED-SHORT and is located in
the third and fourth bytes of the encoding of an operation response.
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If an IPP status-code is returned, then the HTTP status-code MUST be
200 (OK). With any other HTTP status-code value, the HTTP response
MUST NOT contain an IPP message body, and thus no IPP status-code is
returned.
3.4.4. Request-id
The "request-id" field contains the request-id value as defined in
the Model. The value is encoded as a SIGNED-INTEGER and is located
in the fifth through eighth bytes of the encoding.
3.5. Tags
There are two kinds of tags:
o delimiter tags: delimit major sections of the protocol, namely
attributes and data
o value tags: specify the type of each attribute value
Tags are part of the IANA IPP registry [IANA-IPP]
3.5.1. Delimiter Tags
Table 2 specifies the values for the delimiter tags defined in this
document:
+---------------+---------------------------------------------------+
| Tag Value | Meaning |
| (Hex) | |
+---------------+---------------------------------------------------+
| 0x00 | reserved for definition in a future standards |
| | track document |
| 0x01 | "operation-attributes-tag" |
| 0x02 | "job-attributes-tag" |
| 0x03 | "end-of-attributes-tag" |
| 0x04 | "printer-attributes-tag" |
| 0x05 | "unsupported-attributes-tag" |
| 0x06-0x0f | reserved for future delimiters in standards track |
| | documents |
+---------------+---------------------------------------------------+
Table 2: Delimiter Tags
When a "begin-attribute-group-tag" field occurs in the protocol, it
means that zero or more following attributes up to the next delimiter
tag are attributes belonging to the attribute group specified by the
value of the "begin-attribute-group-tag". For example, if the value
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of "begin-attribute-group-tag" is 0x01, the following attributes are
members of the Operations Attributes group.
The "end-of-attributes-tag" (value 0x03) MUST occur exactly once in
an operation and MUST be the last "delimiter-tag". If the operation
has a document-data group, the Document data in that group follows
the "end-of-attributes-tag".
The order and presence of "attribute-group" fields (whose beginning
is marked by the "begin-attribute-group-tag" subfield) for each
operation request and each operation response MUST be that defined in
the Model.
A Printer MUST treat a "delimiter-tag" (values from 0x00 through
0x0F) differently from a "value-tag" (values from 0x10 through 0xFF)
so that the Printer knows there is an entire attribute group as
opposed to a single value.
3.5.2. Value Tags
The remaining tables show values for the "value-tag" field, which is
the first octet of an attribute. The "value-tag" field specifies the
type of the value of the attribute.
Table 3 specifies the "out-of-band" values for the "value-tag" field
defined in this document:
+-------------+-----------------------------------------------------+
| Tag Value | Meaning |
| (Hex) | |
+-------------+-----------------------------------------------------+
| 0x10 | unsupported |
| 0x11 | reserved for 'default' for definition in a future |
| | standards track document |
| 0x12 | unknown |
| 0x13 | no-value |
| 0x14-0x1F | reserved for "out-of-band" values in future |
| | standards track documents. |
+-------------+-----------------------------------------------------+
Table 3: Out of Band Values
Table 4 specifies the integer values for the "value-tag" field:
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+-------------+-----------------------------------------------------+
| Tag Value | Meaning |
| (Hex) | |
+-------------+-----------------------------------------------------+
| 0x20 | reserved for definition in a future standards track |
| | document |
| 0x21 | integer |
| 0x22 | boolean |
| 0x23 | enum |
| 0x24-0x2F | reserved for integer types for definition in future |
| | standards track documents |
+-------------+-----------------------------------------------------+
Table 4: Integer Tags
Table 5 specifies the octetString values for the "value-tag" field
defined in this document:
+-------------+-----------------------------------------------------+
| Tag Value | Meaning |
| (Hex) | |
+-------------+-----------------------------------------------------+
| 0x30 | octetString with an unspecified format |
| 0x31 | dateTime |
| 0x32 | resolution |
| 0x33 | rangeOfInteger |
| 0x34 | begCollection |
| 0x35 | textWithLanguage |
| 0x36 | nameWithLanguage |
| 0x37 | endCollection |
| 0x38-0x3F | reserved for octetString type definitions in future |
| | standards track documents |
+-------------+-----------------------------------------------------+
Table 5: octetString Tags
Table 6 specifies the character-string values for the "value-tag"
field defined in this document:
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+------------+------------------------------------------------------+
| Tag Value | Meaning |
| (Hex) | |
+------------+------------------------------------------------------+
| 0x40 | reserved for definition in a future standards track |
| | document |
| 0x41 | textWithoutLanguage |
| 0x42 | nameWithoutLanguage |
| 0x43 | reserved for definition in a future standards track |
| | document |
| 0x44 | keyword |
| 0x45 | uri |
| 0x46 | uriScheme |
| 0x47 | charset |
| 0x48 | naturalLanguage |
| 0x49 | mimeMediaType |
| 0x4A | memberAttrName |
| 0x4B-0x5F | reserved for character string type definitions in |
| | future standards track documents |
+------------+------------------------------------------------------+
Table 6: String Tags
Note: An attribute value always has a type, which is explicitly
specified by its tag; one such tag value is "nameWithoutLanguage".
An attribute's name has an implicit type, which is keyword.
The values 0x60-0xFF are reserved for future type definitions in
standards track documents.
The tag 0x7F is reserved for extending types beyond the 255 values
available with a single byte. A tag value of 0x7F MUST signify that
the first 4 bytes of the value field are interpreted as the tag
value. Note this future extension doesn't affect parsers that are
unaware of this special tag. The tag is like any other unknown tag,
and the value length specifies the length of a value, which contains
a value that the parser treats atomically. Values from 0x00000000 to
0x3FFFFFFF are reserved for definition in future standards track
documents. The values 0x40000000 to 0x7FFFFFFF are reserved for
vendor extensions.
3.6. Name-Length
The "name-length" field consists of a SIGNED-SHORT and specifies the
number of octets in the immediately following "name" field. The
value of this field excludes the two bytes of the "name-length"
field. For example, if the "name" field contains 'sides', the value
of this field is 5.
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If a "name-length" field has a value of zero, the following "name"
field is empty and the following value is treated as an additional
value for the attribute encoded in the nearest preceding "attribute-
with-one-value" field. Within an attribute group, if two or more
attributes have the same name, the attribute group is malformed (see
[RFC2911bis]). The zero-length name is the only mechanism for multi-
valued attributes.
3.7. (Attribute) Name
The "name" field contains the name of an attribute. The Model
specifies such names.
3.8. Value Length
The "value-length" field consists of a SIGNED-SHORT which specifies
the number of octets in the immediately following "value" field. The
value of this field excludes the two bytes of the "value-length"
field. For example, if the "value" field contains the keyword
(string) value 'one-sided', the value of this field is 9.
For any of the types represented by binary signed integers, the
sender MUST encode the value in exactly four octets.
For any of the types represented by binary signed bytes, the sender
MUST encode the value in exactly one octet.
For any of the types represented by character-strings, the sender
MUST encode the value with all the characters of the string and
without any padding characters.
For "out-of-band" "value-tag" fields defined in this document, such
as 'unsupported', the "value-length" MUST be 0 and the "value" empty;
the "value" has no meaning when the "value-tag" has one of these
"out-of-band" values. For future "out-of-band" "value-tag" fields,
the same rule holds unless the definition explicitly states that the
"value-length" MAY be non-zero and the "value" non-empty
3.9. (Attribute) Value
The syntax types (specified by the "value-tag" field) and most of the
details of the representation of attribute values are defined in the
Model. Table 7 augments the information in the Model and defines the
syntax types from the Model in terms of the 5 basic types defined in
Section 3. The 5 types are US-ASCII-STRING, LOCALIZED-STRING,
SIGNED-INTEGER, SIGNED-SHORT, SIGNED-BYTE, and OCTET-STRING.
+----------------------+--------------------------------------------+
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| Syntax of Attribute | Encoding |
| Value | |
+----------------------+--------------------------------------------+
| textWithoutLanguage, | LOCALIZED-STRING |
| nameWithoutLanguage | |
+----------------------+--------------------------------------------+
| textWithLanguage | OCTET-STRING consisting of 4 fields: a |
| | SIGNED-SHORT which is the number of octets |
| | in the following field, a value of type |
| | natural-language, a SIGNED-SHORT which is |
| | the number of octets in the following |
| | field, and a value of type |
| | textWithoutLanguage. The length of a |
| | textWithLanguage value MUST be 4 + the |
| | value of field a + the value of field c. |
+----------------------+--------------------------------------------+
| nameWithLanguage | OCTET-STRING consisting of 4 fields: a |
| | SIGNED-SHORT which is the number of octets |
| | in the following field, a value of type |
| | natural-language, a SIGNED-SHORT which is |
| | the number of octets in the following |
| | field, and a value of type |
| | nameWithoutLanguage. The length of a |
| | nameWithLanguage value MUST be 4 + the |
| | value of field a + the value of field c. |
+----------------------+--------------------------------------------+
| charset, | US-ASCII-STRING |
| naturalLanguage, | |
| mimeMediaType, | |
| keyword, uri, and | |
| uriScheme | |
+----------------------+--------------------------------------------+
| boolean | SIGNED-BYTE where 0x00 is 'false' and 0x01 |
| | is 'true' |
+----------------------+--------------------------------------------+
| integer and enum | a SIGNED-INTEGER |
+----------------------+--------------------------------------------+
| dateTime | OCTET-STRING consisting of eleven octets |
| | whose contents are defined by |
| | "DateAndTime" in RFC 1903 [RFC1903] |
+----------------------+--------------------------------------------+
| resolution | OCTET-STRING consisting of nine octets of |
| | 2 SIGNED-INTEGERs followed by a SIGNED- |
| | BYTE. The first SIGNED-INTEGER contains |
| | the value of cross feed direction |
| | resolution. The second SIGNED-INTEGER |
| | contains the value of feed direction |
| | resolution. The SIGNED-BYTE contains the |
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| | units value. |
+----------------------+--------------------------------------------+
| rangeOfInteger | Eight octets consisting of 2 SIGNED- |
| | INTEGERs. The first SIGNED-INTEGER |
| | contains the lower bound and the second |
| | SIGNED-INTEGER contains the upper bound. |
+----------------------+--------------------------------------------+
| 1setOf X | Encoding according to the rules for an |
| | attribute with more than 1 value. Each |
| | value X is encoded according to the rules |
| | for encoding its type. |
+----------------------+--------------------------------------------+
| octetString | OCTET-STRING |
+----------------------+--------------------------------------------+
| collection | Encoding as defined in Section 3.1.6. |
+----------------------+--------------------------------------------+
Table 7: Attribute Value Encoding
The attribute syntax type of the value determines its encoding and
the value of its "value-tag".
3.10. Data
The "data" field MUST include any data required by the operation.
4. Encoding of Transport Layer
HTTP/1.1 [RFC7230] is the REQUIRED transport layer for this protocol.
HTTP/2 [RFC7540] is an OPTIONAL transport layer for this protocol.
The operation layer has been designed with the assumption that the
transport layer contains the following information:
o the target URI for the operation
o the total length of the data in the operation layer, either as a
single length or as a sequence of chunks each with a length.
It is REQUIRED that a Printer implementation support HTTP over the
IANA assigned Well Known Port 631 (the IPP default port), though a
Printer implementation may support HTTP over some other port as well.
Each HTTP operation MUST use the POST method where the request-URI is
the object target of the operation, and where the "Content-Type" of
the message body in each request and response MUST be "application/
ipp". The message body MUST contain the operation layer and MUST
have the syntax described in Section 3.2 "Syntax of Encoding". A
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Client implementation MUST adhere to the rules for a Client described
for HTTP [RFC7230]. A Printer (server) implementation MUST adhere
the rules for an origin server described for HTTP [RFC7230].
An IPP server sends a response for each request that it receives. If
an IPP server detects an error, it MAY send a response before it has
read the entire request. If the HTTP layer of the IPP server
completes processing the HTTP headers successfully, it MAY send an
intermediate response, such as "100 Continue", with no IPP data
before sending the IPP response. A Client MUST expect such a variety
of responses from an IPP server. For further information on HTTP,
consult the HTTP documents [RFC7230].
An HTTP/1.1 server MUST support chunking for IPP requests, and an IPP
Client MUST support chunking for IPP responses according to HTTP/1.1
[RFC7230].
4.1. Printer URI, Job URI, and Job ID
All Printer and Job objects are identified by a Uniform Resource
Identifier (URI) [RFC3986] so that they can be persistently and
unambiguously referenced. Jobs can also be identified by a
combination of Printer URI and Job ID.
Some operation elements are encoded twice, once as the request-URI on
the HTTP Request-Line and a second time as a REQUIRED operation
attribute in the application/ipp entity. These attributes are the
target for the operation and are called "printer-uri" and "job-uri".
Note: The target URI is included twice in an operation referencing
the same IPP object, but the two URIs can be different. For example,
the HTTP request URI can be relative while the IPP request URI MUST
be absolute.
HTTP allows Clients to generate and send a relative URI rather than
an absolute URI. A relative URI identifies a resource with the scope
of the HTTP server, but does not include scheme, host or port. The
following statements characterize how URIs are used in the mapping of
IPP onto HTTP:
1. Although potentially redundant, a Client MUST supply the target
of the operation both as an operation attribute and as a URI at
the HTTP layer. The rationale for this decision is to maintain a
consistent set of rules for mapping "application/ipp" to possibly
many communication layers, even where URIs are not used as the
addressing mechanism in the transport layer.
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2. Even though these two URIs might not be literally identical (one
being relative and the other being absolute), they MUST both
reference the same IPP object.
3. The URI in the HTTP layer is either relative or absolute and is
used by the HTTP server to route the HTTP request to the correct
resource relative to that HTTP server.
4. Once the HTTP server resource begins to process the HTTP request,
it can get the reference to the appropriate IPP Printer object
from either the HTTP URI (using to the context of the HTTP server
for relative URIs) or from the URI within the operation request;
the choice is up to the implementation.
5. HTTP URIs can be relative or absolute, but the target URI in the
IPP operation attribute MUST be an absolute URI.
5. IPP URI Schemes
The IPP URI schemes are 'ipp' [RFC3510] and 'ipps' [RFC7472].
Clients and Printers MUST support the ipp-URI value in the following
IPP attributes:
o Job attributes:
* job-uri
* job-printer-uri
o Printer attributes:
* printer-uri-supported
o Operation attributes:
* job-uri
* printer-uri
Each of the above attributes identifies a Printer or Job. The ipp-URI
is intended as the value of the attributes in this list. All of
these attributes have a syntax type of 'uri', but there are
attributes with a syntax type of 'uri' that do not use the 'ipp'
scheme, e.g. "job-more-info".
If a Printer registers its URI with a directory service, the Printer
MUST register an ipp-URI.
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When a Client sends a request, it MUST convert a target ipp-URI to a
target http-URL (or ipps-URI to a target https-URI) for the HTTP
layer according to the following rules:
1. change the 'ipp' scheme to 'http' or 'ipps' scheme to 'https'
2. add an explicit port 631 if the http-URL or https-URL does not
contain an explicit port. Note: port 631 is the IANA assigned
Well Known Port for the 'ipp' and 'ipps' schemes.
The Client MUST use the target http-URL or https-URL in both the HTTP
Request-Line and HTTP headers, as specified by HTTP [RFC7230].
However, the Client MUST use the target ipp-URI or ipps-URI for the
value of the "printer-uri" or "job-uri" operation attribute within
the application/ipp body of the request. The server MUST use the
ipp-URI or ipps-URI for the value of the "printer-uri", "job-uri" or
"printer-uri-supported" attributes within the application/ipp body of
the response.
For example, when an IPP Client sends a request directly, i.e., no
proxy, to an ipp-URI "ipp://printer.example.com/ipp/print/myqueue",
it opens a TCP connection to port 631 (the IPP implicit port) on the
host "printer.example.com" and sends the following data:
POST /ipp/print/myqueue HTTP/1.1
Host: printer.example.com:631
Content-type: application/ipp
Transfer-Encoding: chunked
...
"printer-uri" 'ipp://printer.example.com/ipp/print/myqueue'
(encoded in application/ipp message body)
...
Figure 11: Direct IPP Request
As another example, when an IPP Client sends the same request as
above via a proxy "myproxy.example.com", it opens a TCP connection to
the proxy port 8080 on the proxy host "myproxy.example.com" and sends
the following data:
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POST http://printer.example.com:631/ipp/print/myqueue HTTP/1.1
Host: printer.example.com:631
Content-type: application/ipp
Transfer-Encoding: chunked
...
"printer-uri" 'ipp://printer.example.com/ipp/print/myqueue'
(encoded in application/ipp message body)
...
Figure 12: Proxied IPP Request
The proxy then connects to the IPP origin server with headers that
are the same as the "no-proxy" example above.
6. IANA Considerations
See the section on "IANA Considerations" in the document "Internet
Printing Protocol/1.1: Model and Semantics" [RFC2911bis] for
information on IANA considerations. This document adds no additional
considerations.
7. Internationalization Considerations
See the section on "Internationalization Considerations" in the
document "Internet Printing Protocol/1.1: Model and Semantics"
[RFC2911bis] for information on internationalization. This document
adds no additional issues.
8. Security Considerations
The IPP Model and Semantics document [RFC2911bis] discusses high
level security requirements (Client Authentication, Server
Authentication and Operation Privacy). Client Authentication is the
mechanism by which the Client proves its identity to the server in a
secure manner. Server Authentication is the mechanism by which the
server proves its identity to the Client in a secure manner.
Operation Privacy is defined as a mechanism for protecting operations
from eavesdropping.
8.1. Security Conformance Requirements
This section defines the security requirements for IPP Clients and
IPP objects.
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8.1.1. Digest Authentication
IPP Clients and Printers SHOULD support Digest Authentication
[RFC7616]. If supported, MD5 and MD5-sess MUST be implemented and
supported. Use of the Message Integrity feature (qop="auth-int") is
OPTIONAL.
The reasons that IPP Clients and Printers SHOULD (rather than MUST)
support Digest Authentication are:
1. While Client Authentication is important, there is a certain
class of output devices where it does not make sense.
Specifically, a low-end device with limited ROM space and low
paper throughput may not need Client Authentication. This class
of device typically requires firmware designers to make trade-
offs between protocols and functionality to arrive at the lowest-
cost solution possible. Factored into the designer's decisions
is not just the size of the code, but also the testing,
maintenance, usefulness, and time-to-market impact for each
feature delivered to the customer. Forcing such low-end devices
to provide security in order to claim IPP/1.1 conformance would
not make business sense.
2. Print devices that have high-volume throughput and have available
ROM space are more likely to provide support for Client
Authentication that safeguards the device from unauthorized
access. These devices are prone to a high loss of consumables
and paper if unauthorized access occurs.
8.1.2. Transport Layer Security (TLS)
IPP Clients and Printers SHOULD support Transport Layer Security
(TLS) [RFC5246] [RFC7525] for Server Authentication and Operation
Privacy. IPP Printers MAY also support TLS for Client
Authentication. IPP Clients and Printers MAY support Basic
Authentication [RFC7617] for User Authentication if the channel is
secure.
The IPP Model and Semantics document [RFC2911bis] defines two Printer
attributes ("uri-authentication-supported" and "uri-security-
supported") that the Client can use to discover the security policy
of a Printer. That document also outlines IPP-specific security
considerations and is the primary reference for security implications
with regard to the IPP protocol itself.
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8.2. Using IPP with TLS
IPP uses the "Upgrading to TLS Within HTTP/1.1" mechanism [RFC2817]
for 'ipp' URIs. The Client requests a secure TLS connection by using
the HTTP "Upgrade" header, while the server agrees in the HTTP
response. The switch to TLS occurs either because the server grants
the Client's request to upgrade to TLS, or a server asks to switch to
TLS in its response. Secure communication begins with a server's
response to switch to TLS.
IPP uses the "HTTPS: HTTP over TLS" mechanism [RFC2818] for 'ipps'
URIs. The Client and server negotiate a secure TLS connection
immediately and unconditionally.
9. Interoperability with Other IPP Versions
It is beyond the scope of this specification to mandate conformance
with versions of IPP other than 1.1. IPP was deliberately designed,
however, to make supporting other versions easy. IPP Printer
implementations SHOULD:
o understand any valid request in the format of IPP/1.x or 2.x;
o respond appropriately with a response containing the same
"version-number" parameter value used by the Client in the
request.
IPP Clients SHOULD:
o understand any valid response in the format of IPP/1.1, 2.0, 2.1,
or 2.2.
9.1. The "version-number" Parameter
The following are rules regarding the "version-number" parameter (see
Section 3.3):
1. Clients MUST send requests containing a "version-number"
parameter with the highest supported value, e.g., '1.1', '2.0',
etc., and SHOULD try supplying alternate version numbers if they
receive a 'server-error-version-not-supported' error return in a
response.
2. IPP objects MUST accept requests containing a "version-number"
parameter with a '1.1' value (or reject the request for reasons
other than 'server-error-version-not-supported').
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3. IPP objects SHOULD accept any request with the major version '1'
or '2', or reject the request for reasons other than 'server-
error-version-not-supported'. See [RFC2911bis] "Versions" sub-
section.
4. In any case, security MUST NOT be compromised when a Client
supplies a lower "version-number" parameter in a request. For
example, if an IPP/2.0 conforming Printer accepts version '1.1'
requests and is configured to enforce Digest Authentication, it
MUST do the same for a version '1.1' request.
9.2. Security and URI Schemes
The following are rules regarding security, the "version-number"
parameter, and the URI scheme supplied in target attributes and
responses:
1. When a Client supplies a request, the "printer-uri" or "job-uri"
target operation attribute MUST have the same scheme as that
indicated in one of the values of the "printer-uri-supported"
Printer attribute.
2. When the Printer returns the "job-printer-uri" or "job-uri" Job
Description attributes, it SHOULD return the same scheme ('ipp',
'ipps', etc.) that the Client supplied in the "printer-uri" or
"job-uri" target operation attributes in the Get-Job-Attributes
or Get-Jobs request, rather than the scheme used when the Job was
created. However, when a Client requests Job attributes using
the Get-Job-Attributes or Get-Jobs operations, the Jobs and Job
attributes that the Printer returns depends on: (1) the security
in effect when the Job was created, (2) the security in effect in
the query request, and (3) the security policy in force.
3. The Printer MUST enforce its security and privacy policies based
on the owner of the IPP object and the URI scheme and/or
credentials supplied by the Client in the current request.
10. Changes Since RFC 2910
The following changes have been made since the publication of RFC
2910:
o Added references to current IPP extension specifications.
o Added optional support for HTTP/2.
o Added collection attribute syntax from RFC 3382.
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o Fixed typographical errors.
o Now reference TLS/1.2 and no longer mandate the TLS/1.0 MTI cipher
suites.
o Updated all references.
o Updated document organization to follow current style.
o Updated example ipp: URIs to follow RFC 7472 guidelines.
o Updated version compatibility for all versions of IPP.
o Updated HTTP Digest authentication to optional for Clients.
o Removed references to (experimental) IPP/1.0 and usage of
http:/https: URLs.
11. References
11.1. Normative References
[ASCII] ANSI, "Information Systems - Coded Character Sets - 7-Bit
American National Standard Code for Information
Interchange (7-Bit ASCII)", June 2007.
[PWG5100.12]
Sweet, M. and I. McDonald, "IPP/2.0, 2.1, and 2.2",
October 2015, <http://ftp.pwg.org/pub/pwg/standards/
std-ipp20-20151030-5100.12.pdf>.
[RFC1903] McCloghrie, K., Case, J., Rose, M., and S. Waldbusser,
"Textual Conventions for Version 2 of the Simple Network
Management Protocol (SNMPv2)", RFC 1903, January 1996.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2817] Khare, R. and S. Lawrence, "Upgrading to TLS Within
HTTP/1.1", RFC 2817, May 2000.
[RFC2818] Rescorla, E., "HTTP Over TLS", RFC 2818, May 2000.
[RFC2911bis]
Sweet, M. and I. McDonald, "Internet Printing
Protocol/1.1: Model and Semantics", December 2015,
<https://tools.ietf.org/html/draft-sweet-rfc2911bis>.
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[RFC3510] Herriot, R. and I. McDonald, "Internet Printing
Protocol/1.1: IPP URL Scheme", RFC 3510, April 2003.
[RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO
10646", STD 63, RFC 3629, November 2003.
[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
Resource Identifier (URI): Generic Syntax", STD 66,
RFC 3986, January 2005.
[RFC5234] Crocker, D. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", STD 68, RFC 5234, January 2008.
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246, August 2008.
[RFC7230] Fielding, R. and J. Reschke, "Hypertext Transfer Protocol
(HTTP/1.1): Message Syntax and Routing", RFC 7230, June
2014.
[RFC7231] Fielding, R. and J. Reschke, "Hypertext Transfer Protocol
(HTTP/1.1): Semantics and Content", RFC 7231, June 2014.
[RFC7232] Fielding, R. and J. Reschke, "Hypertext Transfer Protocol
(HTTP/1.1): Conditional Requests", RFC 7232, June 2014.
[RFC7234] Fielding, R., Nottingham, M., and J. Reschke, "Hypertext
Transfer Protocol (HTTP/1.1): Caching", RFC 7234, June
2014.
[RFC7235] Fielding, R. and J. Reschke, "Hypertext Transfer Protocol
(HTTP/1.1): Authentication", RFC 7235, June 2014.
[RFC7472] McDonald, I. and M. Sweet, "Internet Printing Protocol
(IPP) over HTTPS Transport Binding and the 'ipps' URI
Scheme", RFC 7472, March 2015.
[RFC7540] Belshe, M., Peon, R., and M. Thompson, "Hypertext Transfer
Protocol Version 2 (HTTP/2)", May 2015,
<https://tools.ietf.org/html/rfc7540>.
[RFC7541] Peon, R. and H. Ruellan, "HPACK - Header Compression for
HTTP/2", May 2015, <https://tools.ietf.org/html/rfc7541>.
[RFC7616] Shekh-Yusef, R., Ed., Ahrens, D., and S. Bremer, "HTTP
Digest Access Authentication", RFC 7616,
DOI 10.17487/RFC7616, September 2015,
<http://www.rfc-editor.org/info/rfc7616>.
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[RFC7617] Reschke, J., "The 'Basic' HTTP Authentication Scheme",
RFC 7617, DOI 10.17487/RFC7617, September 2015,
<http://www.rfc-editor.org/info/rfc7617>.
[RFC793] Postel, J., "Transmission Control Protocol", STD 7,
RFC 793, September 1981.
11.2. Informative References
[IANA-CON]
Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", BCP 26, RFC 5226,
May 2008.
[IANA-IPP]
"IANA IPP Registry",
<http://www.iana.org/assignments/ipp-registrations/>.
[PWG5100.3]
Ocke, K. and T. Hastings, "IPP Production Printing
Attributes Set 1", February 2001,
<http://ftp.pwg.org/pub/pwg/candidates/
cs-ippprodprint10-20010212-5100.3.pdf>.
[RFC1179] McLaughlin, L., "Line printer daemon protocol", RFC 1179,
August 1990.
[RFC7525] Sheffer, Y., Holz, R., and P. Saint-Andre,
"Recommendations for Secure Use of Transport Layer
Security (TLS) and Datagram Transport Layer Security
(DTLS)", BCP 195, RFC 7525, May 2015.
Appendix A. Protocol Examples
A.1. Print-Job Request
The following is an example of a Print-Job request with "job-name",
"copies", and "sides" specified. The "ipp-attribute-fidelity"
attribute is set to 'true' so that the print request will fail if the
"copies" or the "sides" attribute are not supported or their values
are not supported.
Octets Symbolic Value Protocol field
0x0101 1.1 version-number
0x0002 Print-Job operation-id
0x00000001 1 request-id
0x01 start operation- operation-
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attributes attributes-tag
0x47 charset type value-tag
0x0012 name-length
attributes-charset attributes-charset name
0x0005 value-length
utf-8 UTF-8 value
0x48 natural-language value-tag
type
0x001B name-length
attributes-natural-language attributes-natural- name
language
0x0005 value-length
en-us en-US value
0x45 uri type value-tag
0x000B name-length
printer-uri printer-uri name
0x002C value-length
ipp://printer.example.com/ipp/ printer pinetree value
print/pinetree
0x42 nameWithoutLanguage value-tag
type
0x0008 name-length
job-name job-name name
0x0006 value-length
foobar foobar value
0x22 boolean type value-tag
0x0016 name-length
ipp-attribute-fidelity ipp-attribute- name
fidelity
0x0001 value-length
0x01 true value
0x02 start job-attributes job-attributes-
tag
0x21 integer type value-tag
0x0006 name-length
copies copies name
0x0004 value-length
0x00000014 20 value
0x44 keyword type value-tag
0x0005 name-length
sides sides name
0x0013 value-length
two-sided-long-edge two-sided-long-edge value
0x03 end-of-attributes end-of-
attributes-tag
%!PDF... <PDF Document> data
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A.2. Print-Job Response (successful)
Here is an example of a successful Print-Job response to the previous
Print-Job request. The Printer supported the "copies" and "sides"
attributes and their supplied values. The status code returned is
'successful-ok'.
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Octets Symbolic Value Protocol field
0x0101 1.1 version-number
0x0000 successful-ok status-code
0x00000001 1 request-id
0x01 start operation- operation-
attributes attributes-tag
0x47 charset type value-tag
0x0012 name-length
attributes-charset attributes-charset name
0x0005 value-length
utf-8 UTF-8 value
0x48 natural-language value-tag
type
0x001B name-length
attributes-natural-language attributes- name
natural-language
0x0005 value-length
en-us en-US value
0x41 textWithoutLanguag value-tag
e type
0x000E name-length
status-message status-message name
0x000D value-length
successful-ok successful-ok value
0x02 start job- job-attributes-
attributes tag
0x21 integer value-tag
0x0006 name-length
job-id job-id name
0x0004 value-length
147 147 value
0x45 uri type value-tag
0x0007 name-length
job-uri job-uri name
0x0030 value-length
ipp://printer.example.com/ipp/pr job 147 on value
int/pinetree/147 pinetree
0x23 enum type value-tag
0x0009 name-length
job-state job-state name
0x0004 value-length
0x0003 pending value
0x03 end-of-attributes end-of-
attributes-tag
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A.3. Print-Job Response (failure)
Here is an example of an unsuccessful Print-Job response to the
previous Print-Job request. It fails because, in this case, the
Printer does not support the "sides" attribute and because the value
'20' for the "copies" attribute is not supported. Therefore, no Job
is created, and neither a "job-id" nor a "job-uri" operation
attribute is returned. The error code returned is 'client-error-
attributes-or-values-not-supported' (0x040B).
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Octets Symbolic Value Protocol
field
0x0101 1.1 version-
number
0x040B client-error-attributes-or- status-code
values-not-supported
0x00000001 1 request-id
0x01 start operation-attributes operation-
attributes
tag
0x47 charset type value-tag
0x0012 name-length
attributes-charset attributes-charset name
0x0005 value-length
utf-8 UTF-8 value
0x48 natural-language type value-tag
0x001B name-length
attributes-natural-language attributes-natural-language name
0x0005 value-length
en-us en-US value
0x41 textWithoutLanguage type value-tag
0x000E name-length
status-message status-message name
0x002F value-length
client-error-attributes-or- client-error-attributes-or- value
values-not-supported values-not-supported
0x05 start unsupported- unsupported-
attributes attributes
tag
0x21 integer type value-tag
0x0006 name-length
copies copies name
0x0004 value-length
0x00000014 20 value
0x10 unsupported (type) value-tag
0x0005 name-length
sides sides name
0x0000 value-length
0x03 end-of-attributes end-of-
attributes-
tag
A.4. Print-Job Response (success with attributes ignored)
Here is an example of a successful Print-Job response to a Print-Job
request like the previous Print-Job request, except that the value of
"ipp-attribute-fidelity" is 'false'. The print request succeeds,
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even though, in this case, the Printer supports neither the "sides"
attribute nor the value '20' for the "copies" attribute. Therefore,
a Job is created, and both a "job-id" and a "job-uri" operation
attribute are returned. The unsupported attributes are also returned
in an Unsupported Attributes Group. The error code returned is
'successful-ok-ignored-or-substituted-attributes' (0x0001).
Octets Symbolic Value Protocol field
0x0101 1.1 version-number
0x0001 successful-ok-ignored-or- status-code
substituted-attributes
0x00000001 1 request-id
0x01 start operation-attributes operation-
attributes-tag
0x47 charset type value-tag
0x0012 name-length
attributes-charset attributes-charset name
0x0005 value-length
utf-8 UTF-8 value
0x48 natural-language type value-tag
0x001B name-length
attributes-natural- attributes-natural-language name
language
0x0005 value-length
en-us en-US value
0x41 textWithoutLanguage type value-tag
0x000E name-length
status-message status-message name
0x002F value-length
successful-ok-ignored-or- successful-ok-ignored-or- value
substituted-attributes substituted-attributes
0x05 start unsupported- unsupported-
attributes attributes tag
0x21 integer type value-tag
0x0006 name-length
copies copies name
0x0004 value-length
0x00000014 20 value
0x10 unsupported (type) value-tag
0x0005 name-length
sides sides name
0x0000 value-length
0x02 start job-attributes job-
attributes-tag
0x21 integer value-tag
0x0006 name-length
job-id job-id name
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0x0004 value-length
147 147 value
0x45 uri type value-tag
0x0007 name-length
job-uri job-uri name
0x0030 value-length
ipp://printer.example.com/ job 147 on pinetree value
ipp/print/pinetree/147
0x23 enum type value-tag
0x0009 name-length
job-state job-state name
0x0004 value-length
0x0003 pending value
0x03 end-of-attributes end-of-
attributes-tag
A.5. Print-URI Request
The following is an example of Print-URI request with "copies" and
"job-name" parameters:
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Octets Symbolic Value Protocol field
0x0101 1.1 version-number
0x0003 Print-URI operation-id
0x00000001 1 request-id
0x01 start operation- operation-
attributes attributes-tag
0x47 charset type value-tag
0x0012 name-length
attributes-charset attributes-charset name
0x0005 value-length
utf-8 UTF-8 value
0x48 natural-language value-tag
type
0x001B name-length
attributes-natural-language attributes-natural- name
language
0x0005 value-length
en-us en-US value
0x45 uri type value-tag
0x000B name-length
printer-uri printer-uri name
0x002C value-length
ipp://printer.example.com/ipp/ printer pinetree value
print/pinetree
0x45 uri type value-tag
0x000C name-length
document-uri document-uri name
0x0019 value-length
ftp://foo.example.com/foo ftp://foo.example.co value
m/foo
0x42 nameWithoutLanguage value-tag
type
0x0008 name-length
job-name job-name name
0x0006 value-length
foobar foobar value
0x02 start job-attributes job-attributes-
tag
0x21 integer type value-tag
0x0006 name-length
copies copies name
0x0004 value-length
0x00000001 1 value
0x03 end-of-attributes end-of-
attributes-tag
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A.6. Create-Job Request
The following is an example of Create-Job request with no parameters
and no attributes:
Octets Symbolic Value Protocol field
0x0101 1.1 version-number
0x0005 Create-Job operation-id
0x00000001 1 request-id
0x01 start operation- operation-
attributes attributes-tag
0x47 charset type value-tag
0x0012 name-length
attributes-charset attributes-charset name
0x0005 value-length
utf-8 UTF-8 value
0x48 natural-language value-tag
type
0x001B name-length
attributes-natural-language attributes-natural- name
language
0x0005 value-length
en-us en-US value
0x45 uri type value-tag
0x000B name-length
printer-uri printer-uri name
0x002C value-length
ipp://printer.example.com/ipp/ printer pinetree value
print/pinetree
0x03 end-of-attributes end-of-
attributes-tag
A.7. Create-Job Request with Collection Attributes
The following is an example of Create-Job request with the "media-
col" collection attribute [PWG5100.3] with the value "media-
size={x-dimension=21000 y-dimension=29700} media-type='stationery'":
Octets Symbolic Value Protocol field
0x0101 1.1 version-number
0x0005 Create-Job operation-id
0x00000001 1 request-id
0x01 start operation- operation-
attributes attributes-tag
0x47 charset type value-tag
0x0012 name-length
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attributes-charset attributes-charset name
0x0005 value-length
utf-8 UTF-8 value
0x48 natural-language value-tag
type
0x001B name-length
attributes-natural-language attributes-natural- name
language
0x0005 value-length
en-us en-US value
0x45 uri type value-tag
0x000B name-length
printer-uri printer-uri name
0x002C value-length
ipp://printer.example.com/ipp/ printer pinetree value
print/pinetree
0x34 begCollection value-tag
0x0009 9 name-length
media-col media-col name
0x0000 0 value-length
0x4A memberAttrName value-tag
0x0000 0 name-length
0x000A 10 value-length
media-size media-size value (member-
name)
0x34 begCollection member-value-tag
0x0000 0 name-length
0x0000 0 member-value-
length
0x4A memberAttrName value-tag
0x0000 0 name-length
0x000B 11 value-length
x-dimension x-dimension value (member-
name)
0x21 integer member-value-tag
0x0000 0 name-length
0x0004 4 member-value-
length
0x00005208 21000 member-value
0x4A memberAttrName value-tag
0x0000 0 name-length
0x000B 11 value-length
y-dimension y-dimension value (member-
name)
0x21 integer member-value-tag
0x0000 0 name-length
0x0004 4 member-value-
length
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0x00007404 29700 member-value
0x37 endCollection end-value-tag
0x0000 0 end-name-length
0x0000 0 end-value-length
0x4A memberAttrName value-tag
0x0000 0 name-length
0x000A 10 value-length
media-type media-type value (member-
name)
0x44 keyword member-value-tag
0x0000 0 name-length
0x000A 10 member-value-
length
stationery stationery member-value
0x37 endCollection end-value-tag
0x0000 0 end-name-length
0x0000 0 end-value-length
0x03 end-of-attributes end-of-
attributes-tag
A.8. Get-Jobs Request
The following is an example of Get-Jobs request with parameters but
no attributes:
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Octets Symbolic Value Protocol field
0x0101 1.1 version-number
0x000A Get-Jobs operation-id
0x0000007B 123 request-id
0x01 start operation- operation-
attributes attributes-tag
0x47 charset type value-tag
0x0012 name-length
attributes-charset attributes-charset name
0x0005 value-length
utf-8 UTF-8 value
0x48 natural-language value-tag
type
0x001B name-length
attributes-natural-language attributes-natural- name
language
0x0005 value-length
en-us en-US value
0x45 uri type value-tag
0x000B name-length
printer-uri printer-uri name
0x002C value-length
ipp://printer.example.com/ipp/ printer pinetree value
print/pinetree
0x21 integer type value-tag
0x0005 name-length
limit limit name
0x0004 value-length
0x00000032 50 value
0x44 keyword type value-tag
0x0014 name-length
requested-attributes requested-attributes name
0x0006 value-length
job-id job-id value
0x44 keyword type value-tag
0x0000 additional value name-length
0x0008 value-length
job-name job-name value
0x44 keyword type value-tag
0x0000 additional value name-length
0x000F value-length
document-format document-format value
0x03 end-of-attributes end-of-
attributes-tag
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A.9. Get-Jobs Response
The following is an of Get-Jobs response from previous request with 3
jobs. The Printer returns no information about the second Job
(because of security reasons):
Octets Symbolic Value Protocol field
0x0101 1.1 version-number
0x0000 successful-ok status-code
0x0000007B 123 request-id (echoed
back)
0x01 start operation- operation-attributes-
attributes tag
0x47 charset type value-tag
0x0012 name-length
attributes-charset attributes-charset name
0x0005 value-length
utf-8 UTF-8 value
0x48 natural-language type value-tag
0x001B name-length
attributes-natural- attributes-natural- name
language language
0x0005 value-length
en-us en-US value
0x41 textWithoutLanguage value-tag
type
0x000E name-length
status-message status-message name
0x000D value-length
successful-ok successful-ok value
0x02 start job-attributes job-attributes-tag
(1st object)
0x21 integer type value-tag
0x0006 name-length
job-id job-id name
0x0004 value-length
147 147 value
0x36 nameWithLanguage value-tag
0x0008 name-length
job-name job-name name
0x000C value-length
0x0005 sub-value-length
fr-ca fr-CA value
0x0003 sub-value-length
fou fou name
0x02 start job-attributes job-attributes-tag
(2nd object)
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0x02 start job-attributes job-attributes-tag
(3rd object)
0x21 integer type value-tag
0x0006 name-length
job-id job-id name
0x0004 value-length
148 149 value
0x36 nameWithLanguage value-tag
0x0008 name-length
job-name job-name name
0x0012 value-length
0x0005 sub-value-length
de-CH de-CH value
0x0009 sub-value-length
isch guet isch guet name
0x03 end-of-attributes end-of-attributes-tag
Appendix B. Registration of MIME Media Type Information for
"application/ipp"
This section is strictly informative. The MIME media type listed in
this section should not be re-registered by IANA when this document
is published.
This appendix contains the information that IANA requires for
registering a MIME media type. The information following this
paragraph will be forwarded to IANA to register application/ipp whose
contents are defined in Section 3 "Encoding of the Operation Layer"
in this document:
MIME type name: application
MIME subtype name: ipp
A Content-Type of "application/ipp" indicates an Internet Printing
Protocol message body (request or response) whose syntax is described
in Section 3 "Encoding of the Operation Layer" of [RFC2910bis], and
whose semantics are described in [RFC2911bis].
Required parameters: none
Optional parameters: none
Encoding considerations:
IPP protocol requests/responses MAY contain long lines and ALWAYS
contain binary data (for example attribute value lengths).
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Security considerations:
IPP protocol requests/responses do not introduce any security risks
not already inherent in the underlying transport protocols. Protocol
mixed-version interworking rules in [RFC2911bis] as well as protocol
encoding rules in [RFC2910bis] are complete and unambiguous.
Interoperability considerations:
IPP requests (generated by clients) and responses (generated by
servers) MUST comply with all conformance requirements imposed by the
normative specifications [RFC2911bis] and [RFC2910bis]. Protocol
encoding rules specified in [RFC2910bis] are comprehensive, so that
interoperability between conforming implementations is guaranteed
(although support for specific optional features is not ensured).
Both the "charset" and "natural-language" of all IPP attribute values
which are a LOCALIZED-STRING are explicit within IPP protocol
requests/responses (without recourse to any external information in
HTTP, SMTP, or other message transport headers).
Published specifications:
[RFC2911bis] Sweet, M., McDonald, I., "Internet Printing
Protocol/1.1: Model and Semantics" draft-sweet-rfc2911bis-06.txt,
December, 2015.
[RFC2910bis] Sweet, M., McDonald, I., "Internet Printing
Protocol/1.1: Encoding and Transport", draft-sweet-rfc2910bis-07.txt,
December, 2015.
Applications which use this media type:
Internet Printing Protocol (IPP) print clients and print servers,
communicating using HTTP (see [RFC2910bis]), SMTP/ESMTP, FTP, or
other transport protocol. Messages of type "application/ipp" are
self-contained and transport-independent, including "charset" and
"natural-language" context for any LOCALIZED-STRING value.
Appendix C. Acknowledgements
The authors would like to acknowledge the following individuals for
their contributions to the original IPP/1.1 specification:
Robert Herriot (original RFC 2910 editor), Paul Moore, Sylvan Butler,
Randy Turner, and John Wenn
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Appendix D. Change History
D.1. Changes In -07
The following changes are in draft-sweet-rfc2910bis-06:
o Global: Drop RFC2911bis references after "Model".
o Section 1.1: Fix typo.
o Section 4: Drop note about non-conforming HTTP/1.1 servers.
D.2. Changes In -06
The following changes are in draft-sweet-rfc2910bis-06:
o Global: "Model" changed to just "Model".
o Global: "message-body" changed to "message body".
o Abstract: "MIME" instead of "mime" plus some minor rewording.
o Section 1: Updated references to HTTP Basic and Digest, clarify
that the semantics/model are defined in both the Model and
subsequent extensions.
o Section 2.2: Fixed some typos and added a definition of Model.
o Section 3.1.1: Reworded paragraph about the data field.
o Section 3.2: Reworded and now use figure references, and fixed
section references in figures.
o Section 3.3: Added table reference, fix typo.
o Section 3.4.1: Replace "this document" with reference to 2911bis.
o Section 3.4.3: HTTP status-code (to be consistent with RFC 7230).
o Section 3.5.1: Add table references, capitalize Document, reword
ordering requirements, reword printer requirements.
o Section 3.5.2: Add table references, dropped notes (15 years
without needing it, we don't need the note...)
o Section 3.6: "mal-formed" changed to "malformed", fix RFC2911bis
reference, single quotes around value.
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o Section 3.8: "string" instead of "text", use single quotes for
values.
o Section 3.9: Add table reference.
o Section 4: Fix HTTP references and put Note in a separate
paragraph.
o Section 4.1: Mention the Job ID, clean up Note and get rid of
"NEED NOT" language.
o Section 5: Clients and Printers MUST support, drop "object", use
double quotes around attribute names, drop discussion of UI, fix
typos.
o Section 6: Point to RFC2911bis.
o Section 8.1.1: Update references to HTTP Basic and Digest RFCs.
o Section 9: Allow 1.x and 2.x, fix typos.
o Section 11.1: Updated 5100.12, HTTP Basic and Digest references
o Appendix A: Examples now use UTF-8, fix job-uri to be consistent
with job-id.
o
D.3. Changes In -05
The following changes are in draft-sweet-rfc2910bis-05:
o Submission type is now IETF (AD-sponsored), clarify goals.
o Abstract: This document does not define the 'ipp' URI scheme.
o Section 5: drop reference to RFC 2617
o Section 8.1.1: combine identical Client and Printer requirements
o Section 8.1.2: also applies to clients, HTTP Basic is User
authentication, not Client authentication.
o References to RFC 2617 are updated to the updated drafts in the
RFC editor's queue
o Global: Client, Printer, and Job are defined terms, capitalize
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D.4. Changes In -04
The following changes are in draft-sweet-rfc2910bis-04:
o Removed more references to IPP/1.0.
o Section 5: Be explicit about ipp/s-URI and http/s-URL
o Section 9.1: Reword SHOULD recommendation (avoid passive voice)
o Section 9.2: Reword item 3: the server MUST NOT compromise
security...
o Make sure to use URI for generic schemes and URL for HTTP/HTTPS.
o Fixed incorrect usage of lowercase conformance words.
D.5. Changes In -03
The following changes are in draft-sweet-rfc2910bis-03:
o New HTTP/2 RFCs: 7540, 7541
o Added informative reference to UTA BCP (RFC 7525)
o Culled list of people in acknowledgements to the original RFC 2910
editors, per IPP F2F.
D.6. Changes In -02
The following changes are in draft-sweet-rfc2910bis-02:
o Sections 3.1.x: Dropped "Picture of the encoding of" from titles
o Section 3.4.1: Added reference to IPP version interoperability
section.
o Section 3.4.2: Removed paragraph on status-code as operation
attribute (already covered in 3.4 intro) and updated HTTP status
code 200 name (OK)
o Section 3.5: Added reference to IANA IPP registry for tags.
o Section 3.8: Mention SIGNED-BYTE is 1 octet.
o Section 4.1: Drop mention of URIs not being widely implemented,
and that implementations will pass around URLs (not true). Also
remove more "need not" text.
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o Section 6: Fixed references.
o Section 8.1.1: Make Digest authentication a SHOULD for clients.
o Section 9: Reworked for generic IPP version compatibility.
o Section 9.1: Reworked for IPP 2.x compatibility.
o Section 9.2: Drop reference to IPP/1.0 and http/https URI schemes.
o Appendix A: Updated example URIs to follow IETF and IPP/IPPS URI
examples
o Global: ipp-URL tp ipp-URI, URL to URI
o Global: Don't use conformance language for statements of fact.
o Global: Change "NOTE:" to "Note:" for consistency.
D.7. Changes In -01
The following changes are in draft-sweet-rfc2910bis-01:
o Errata ID 4100: Cleaned up TLS references and recommendations - no
longer include cipher suites.
o Errata ID 4172: Fixed range of standards-track value tags (to
0x3ffffff not 0x37777777)
o Updated RFC references.
o Added HTTP/2 references, made it clear that only HTTP/1.1 is
required and HTTP/2 is optional.
o Added collection attribute encoding from RFC 3382.
Authors' Addresses
Michael Sweet
Apple Inc.
1 Infinite Loop
MS 111-HOMC
Cupertino, CA 95014
US
Email: msweet@apple.com
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Ira McDonald
High North, Inc.
PO Box 221
Grand Marais, MI 49839
US
Phone: +1 906-494-2434
Email: blueroofmusic@gmail.com
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