Network Working Group                                          A. Newton
Internet-Draft                                                      ARIN
Intended status: Standards Track                             B. Ellacott
Expires: March 25, June 8, 2013                                              APNIC
                                                                 N. Kong
                                                                   CNNIC
                                                      September 21,
                                                        December 5, 2012

      Using the Registration Data Access Protocol (RDAP) with HTTP
                    draft-ietf-weirds-using-http-00
                    draft-ietf-weirds-using-http-01

Abstract

   This document describes the usage of the Registration Data Access
   Protocol (RDAP) using HTTP.

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
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   This Internet-Draft will expire on March 25, June 8, 2013.

Copyright Notice

   Copyright (c) 2012 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

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   described in the Simplified BSD License.

Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  4
   3.  Design Intents . . . . . . . . . . . . . . . . . . . . . . . .  5
   4.  Queries  . . . . . . . . . . . . . . . . . . . . . . . . . . .  6
     4.1.  Accept Header  . . . . . . . . . . . . . . . . . . . . . .  6
     4.2.  Query Parameters . . . . . . . . . . . . . . . . . . . . .  6
   5.  Types of HTTP Response . . . . . . . . . . . . . . . . . . . .  7
     5.1.  Positive Answers . . . . . . . . . . . . . . . . . . . . .  7
     5.2.  Redirects  . . . . . . . . . . . . . . . . . . . . . . . .  7
     5.3.  Negative Answers . . . . . . . . . . . . . . . . . . . . .  7
     5.4.  Malformed Queries  . . . . . . . . . . . . . . . . . . . .  7
   6.  Use of JSON  . . . . . . . . . . . . . . . . . . . . . . . . .  8
     6.1.  Signaling  Extensibility  . . . . . . . . . . . . . . . . . . . . . . . .  8
     6.2.  Naming .
   7.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . .  9
   8.  Internationalization Considerations  . . . .  8
   7.  Use of XML . . . . . . . . . 10
     8.1.  URIs and IRIs  . . . . . . . . . . . . . . . . . 11
     7.1.  Signaling . . . . . 10
     8.2.  Language Identifiers in Queries and Responses  . . . . . . 10
     8.3.  Language Identifiers in HTTP Headers . . . . . . . . . . . 10
   9.  Normative References . . 11
     7.2.  Naming and Structure . . . . . . . . . . . . . . . . . . . 11
   8.  Common Error Response Body . . . . . . . . . . . . . . . .
   Appendix A.  Cache Busting . . 13
   9.  Common Data Structures . . . . . . . . . . . . . . . . . . 12
   Appendix B.  Changelog . . 14
   10. Common Datatypes . . . . . . . . . . . . . . . . . . . . 13
   Authors' Addresses . . . 16
   11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17
     11.1. IANA Registry 14

1.  Introduction

   This document describes the usage of HTTP for RDAP Extensions  . . . . . . . . . . . . 17
     11.2. Registration Data
   Directory Services running on RESTful web servers.  The goal of RDAP Media Type this
   document is to tie together the usage patterns of HTTP into a common
   profile applicable to the various types of Directory Services serving
   Registration Data using RESTful styling.  By giving the various
   Directory Services common behavior, a single client is better able to
   retrieve data from Directory Services adhering to this behavior.

   In designing these common usage patterns, this draft endeavours to
   satisfy requirements for JSON . . . . . . . . . 18
     11.3. a Registration Data Access Protocol (RDAP)
   that is documented in [draft-kucherawy-weirds-requirements].  This
   draft also introduces an additional design consideration to define a
   simple use of RDAP Media Type for XML  . . . . . . . . . 18
   12. Internationalization Considerations  . . . . . . . . . . . . . 20
     12.1. URIs vs IRIs . . . . . . . . . . . . . . . . . . . . . . . 20
     12.2. Character Encoding . . . . . . . . . . . . . . . . . . . . 20
   13. Normative References . . . . . . . . . . . . . . . . . . . . . 21
   Appendix A.  Cache Busting . . . . . . . . . . . . . . . . . . . . 23
   Appendix B.  Changelog . . . . . . . . . . . . . . . . . . . . . . 24
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 25

1.  Introduction

   This document describes the usage of HTTP for Registration Data
   Directory Services running on RESTful web servers.  The goal of this
   document is to tie together the usage patterns of HTTP into a common
   profile applicable to the various types of Directory Services serving
   Registration Data using RESTful styling.  By giving the various
   Directory Services common behavior, a single client is better able to
   retrieve data from Directory Services adhering to this behavior.

   In designing these common usage patterns, this draft endeavours to
   satisfy requirements for a Registration Data Access Protocol (RDAP)
   that is documented in [draft-kucherawy-weirds-requirements].  This
   draft also introduces an additional design consideration to define a
   simple use of HTTP.  Where complexity may reside, it is the goal of
   this specification to place it upon the server and to keep the client
   as simple as possible.  A client should be possible using common
   operating system scripting tools.

   This is the basic usage pattern for this protocol:

   1.  A client issues an HTTP query using GET.  As an example, a query
       for the network registration 192.168.0.0 might be
       http://example.com/ip/192.168.0.0.

   2.  If the receiving server has the information for the query, it
       examines the Accept header field of the query and returns a 200
       response with a response entity appropriate for the requested
       format.

   3.  If the receiving server does not have the information for the
       query but does have knowledge of where the information can be
       found, it will return a redirection response (3xx) with the
       Redirect header containing an HTTP URL pointing to the
       information.  The client is expected to re-query using that HTTP
       URL.

   4.  If the receiving server does not have the information being
       requested and does not have knowledge of where the information
       can be found, it should return a 404 response.

   It is important to note that it is not the intent of this document to
   redefine the meaning and semantics of HTTP.  The purpose of this
   document is to clarify the use of standard HTTP mechanisms for this
   application.

2.  Terminology

   As is noted in SSAC Report on WHOIS Terminology and Structure
   [SAC-051], the term "Whois" is overloaded, often referring to a
   protocol, a service and data.  In accordance with [SAC-051], this
   document describes the base behavior for a Registration Data Access
   Protocol (RDAP).  [SAC-051] describes a protocol profile of RDAP for
   Doman Name Registries (DNRs), DNRD-AP.  This document and others from
   the IETF WEIRDS working group describe a single protocol, RDAP, for
   access to the data of both DNRs and Regional Internet Registries
   (RIRs).  RIRs are also often refered to as number resource registries
   and are responsible for the registration of IP address networks and
   autonomous system numbers.

3.  Design Intents

   There are a few design criteria this document attempts to support.

   First, each query is meant to return either zero or one result.  With
   the maximum upper bound being set to one, the issuance of redirects
   is simplified to the known query/respone model used by HTTP
   [RFC2616].  Should a result contain more than one result, some of
   which are better served by other servers, the redirection model
   becomes much more complicated.

   Second, multiple response formats are supported by this protocol.
   This document outlines the base usage of JSON and XML, but server
   operators may support other formats as they desire if appropriate.

   Third, HTTP offers a number of transport protocol mechanisms not
   described further in this document.  Operators are able to make use
   of these mechanisms according to their local policy, including cache
   control, authorization, compression, and redirection.  HTTP also
   benefits from widespread investment in scalability, reliability, and
   performance, and widespread programmer understanding of client
   behaviours for RESTful web services, reducing the cost to deploy
   Registration Data Directory Services and clients.

4.  Queries

4.1.  Accept Header

   Clients SHOULD put the media type of the format they desire in the
   Accept header field, and SHOULD use the Accept header parameter
   "level" to indicate the version of the format acceptable [RFC2616].

     Accept: applicaiton/rdap+json;level=0

                                 Figure 1

   Servers SHOULD respond with an appropriate media type in the Content-
   Type header in accordance with the preference rules for the Accept
   header in HTTP [RFC2616].  Servers SHOULD affix a media type
   parameter of "level" appropriate to the version of the format being
   sent.

     Content-Type: application/rdap+json;level=0

                                 Figure 2

   Clients MAY use a generic media type for the desired data format of
   the response (e.g. "application/json"), but servers SHOULD respond
   with the most appropriate media type and corresponding level (e.g.
   "application/rdap+json;level=0").  In other words, a client may use
   "application/json" to express that it desires JSON or "application/
   weirds_blah+json" to express that it desires WEIRDS BLAH in JSON.
   The server MUST respond with "application/rdap+json;level=0".

4.2.  Query Parameters

   Servers SHOULD ignore unknown query parameters.  Use of unknown query
   parameters for cache-busting is described in Appendix A.

5.  Types of HTTP Response

   This section describes the various types of responses a server may
   send to a client.  While no standard HTTP response code is forbidden
   in usage, at a minimum clients should understand the response codes
   described in this section.  It is expected that usage of response
   codes and types for this application not defined here will be
   described in subsequent documents.

5.1.  Positive Answers

   If a server has the information requested by the client and wishes to
   respond to the client with the information according to its policies,
   it should encode the answer in the format most appropriate according
   to the standard and defined rules for processing the HTTP Accept
   header, and return that answer in the body of a 200 response.

5.2.  Redirects

   If a server wishes to inform a client that the answer to a given
   query can be found elsewhere, it SHOULD return either a 301 or a 307
   response code and an HTTP URL in the Redirect header.  The client is
   expected to issue a subsequent query using the given URL without any
   processing of the URL.  In other words, the server is to hand back a
   complete URL and the client should not have to transform the URL to
   follow it.

   A server should use a 301 response to inform the client of a
   permanent move and a 307 response otherwise.  For this application,
   such an example of a permanent move might be a TLD operator informing
   a client the information being sought can be found with another TLD
   operator (i.e. a query for the domain bar in foo.example is found at
   http://foo.example/domain/bar).

5.3.  Negative Answers

   If a server wishes to respond that it has no information regarding
   the query, it SHOULD return a 404 response code.  Optionally, it may
   include additional information regarding the lack of information as
   defined by Section 8.

5.4.  Malformed Queries

   If a server receives a query which it cannot understand, it SHOULD
   return a 400 response code.  Optionally, it may include additional
   information about why it does not understand the query as defined by
   Section 8.

6.  Use of JSON

6.1.  Signaling

   Clients may signal their desire for JSON using the "application/json"
   media type or a more application specific JSON media type.

6.2.  Naming

   Clients processing JSON [RFC4627] responses SHOULD ignore values
   associated with unrecognized names.  Servers MAY insert values
   signified by names into HTTP.  Where complexity may reside, it is the JSON responses which are not specified in
   this document.  Insertion goal of unspecified values into JSON responses
   SHOULD have names prefixed with a short identifier followed by an
   underscore followed by a meaningful name.

   For example, a JSON object may have "handle" and "remarks" formally
   documented in a specification.  Clients adhering to that
   this specification will have appropriate knowledge of to place it upon the meaning of
   "handle" server and "remarks".

   Consider the following JSON response with JSON names.

     {
       "handle" : "ABC123",
       "remarks" : [
         "she sells seas shells",
         "down by the seashore"
       ]
     }

                                 Figure 3

   If The Registry of the Moon desires to express information not found
   in keep the specification, it might select "lunarNic" client
   as its identifying
   prefix and insert, simple as an example, the name
   "lunarNic_beforeOneSmallStep" to signify registrations occuring
   before the first moon landing and the name
   "lunarNic_harshMistressNotes" containing other descriptive text.

   Consider the following JSON response with JSON names, some of which possible.  A client implementation should be ignored by clients without knowledge of their meaning.

     {
       "handle" : "ABC123",
       "lunarNic_beforeOneSmallStep" : "TRUE THAT!",
       "remarks" : [
         "she sells seas shells",
         "down by possible
   using common operating system scripting tools.

   This is the seashore"
       ],
       "lunarNic_harshMistressNotes" : [
         "In space,",
         "nobody can hear you scream."
       ]
     }

                                 Figure 4

   Insertion of unrecognized names ignored by clients may also be used basic usage pattern for future revisions to specifications and specifications deriving
   extensions from this protocol:

   1.  A client issues an HTTP query using GET.  As an example, a base specification.

   JSON names SHOULD only consist of query
       for the alphabetic ASCII characters A
   through Z in both uppercase and lowercase, network registration 192.0.2.0 might be
       http://example.com/ip/192.0.2.0.

   2.  If the numerical digits 0
   through 9, underscore characters, and SHOULD NOT begin with an
   underscore character, numerical digit or receiving server has the characters "xml".  The
   following describes information for the query, it
       examines the produciton Accept header field of JSON names in ABNF [RFC5234].

   ABNF for JSON names

     name = ALPHA *( ALPHA / DIGIT / "_" )

                                 Figure 5

   This restriction is the query and returns a 200
       response with a union response entity appropriate for the requested
       format.

   3.  If the receiving server does not have the information for the
       query but does have knowledge of where the Ruby programming language
   identifier syntax and information can be
       found, it will return a redirection response (3xx) with the XML element name syntax and has two
   purposes.  First, client implementers using modern programming
   languages such as Ruby or Java may use libraries that automatically
   promote JSON names
       Location: header containing an HTTP URL pointing to first order object attributes the
       information or members (e.g.
   using another server known to have knowledge of the example above,
       location of the values may be referenced as
   network.handle or network.lunarNic_beforeOneSmallStep).  Second, a
   clean mapping between JSON and XML information.  The client is easy expected to accomplish re-query
       using that HTTP URL.

   4.  If the
   JSON representation.

   Clients processing JSON responses MUST be prepared for values
   specified in receiving server does not have the registry response documents to information being
       requested and does not have knowledge of where the information
       can be absent from found, it should return a
   response as no JSON value listed 404 response.

   It is required important to appear in the
   response.  In other words, servers MAY remove values as note that it is needed by not the policies intent of this document to
   redefine the server operator.

7.  Use meaning and semantics of XML

7.1.  Signaling

   Clients may signal their desire for XML using HTTP.  The purpose of this
   document is to clarify the "application/xml"
   media type or a more application specific XML media type.

7.2.  Naming use of standard HTTP mechanisms for this
   application.

2.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and Structure

   Well-formed XML may be programmatically produced using the JSON
   encodings due "OPTIONAL" in this
   document are to the JSON naming rules outlined be interpreted as described in RFC 2119 [RFC2119].

   As is noted in Section 6.2 SSAC Report on WHOIS Terminology and Structure
   [SAC-051], the following simple rules:

   1.  Where a JSON name term "Whois" is given, overloaded, often referring to a
   protocol, a service and data.  In accordance with [SAC-051], this
   document describes the corresponding XML element has base behavior for a Registration Data Access
   Protocol (RDAP).  [SAC-051] describes a protocol profile of RDAP for
   Doman Name Registries (DNRs), DNRD-AP.  This document and others from
   the
       same name.

   2.  Where IETF WEIRDS working group describe a JSON value is found, it is single protocol, RDAP, for
   access to the content data of both DNRs and Regional Internet Registries
   (RIRs).  RIRs are also often referred to as number resource
   registries and are responsible for the
       corresponding XML element. registration of IP address
   networks and autonomous system numbers.

3.  Where  Design Intents

   There are a JSON value few design criteria this document attempts to support.

   First, each query is an array, meant to return either zero or one result.  With
   the XML element is maximum upper bound being set to be repeated
       for each element of one, the array.

   4.  The root tag issuance of the XML document redirects
   is simplified to be "response".

   Consider the following JSON response.

     {
       "startAddress" : "10.0.0.0",
       "endAddress" : "10.0.0.255",
       "remarks" : [
         "she sells seas shells",
         "down known query/respone model used by HTTP
   [RFC2616].  Should a result contain more than one result, some of
   which are better served by other servers, the seashore"
       ],
       "uris" : [
         {
           "type" : "source",
           "uri" : "http://whois-rws.net/network/xxxx"
         },
         {
           "type" : "parent",
           "uri" : "http://whois-rws.net/network/yyyy"
         }
       ]
     }

                                 Figure 6

   The corresponding XML would look like this:

     <response>
         <startAddress>10.0.0.0</startAddress>
         <endAddress>10.0.0.255</endAddress>
         <remarks>She sells sea shells</remarks>
         <remarks>down redirection model
   becomes much more complicated.

   Second, multiple response formats are supported by this protocol.  At
   present the seashore</remarks>
         <uris>
             <type>source</type>
             <uri>http://whois-rws.net/network/xxxx</uri>
         </uris>
         <uris>
             <type>parent</type>
             <uri>http://whois-rws.net/network/yyyy</uri>
         </uris>
     </response> IETF WEIRDS working group is defining only a JSON values converted to XML element content MUST be properly
   escaped.  XML offers various means for escaping data,
   [RFC4627] response format, but such
   escaping MUST account for the '<', '>', and '&' characters and MUST
   redact all C0 control characters except tab, carriage return, and
   new-line.  (Redaction of disallowed control characters is server operators may use other data
   formats when those formats are requested.

   Third, HTTP offers a number of transport protocol
   requirement, though in practice most Internet registries do mechanisms not allow
   this data
   described further in this document.  Operators are able to make use
   of these mechanisms according to their data stores local policy, including cache
   control, authorization, compression, and therefore do not need to account
   for this rule.)

   The rules redirection.  HTTP also
   benefits from widespread investment in scalability, reliability, and
   performance, and widespread programmer understanding of client
   behaviours for clients processing XML responses are RESTful web services, reducing the same as those
   with JSON: clients SHOULD ignore unrecognized XML elements, cost to deploy
   Registration Data Directory Services and
   servers MAY insert XML elements clients.

4.  Queries

4.1.  Accept Header

   Clients SHOULD put the media type of the format they desire in the
   Accept header field.

      Accept: application/rdap

   Servers SHOULD respond with tag names according to an appropriate media type in the
   naming rules Content-
   Type header in Section 6.2.  And as accordance with JSON, clients MUST be
   prepared the preference rules for XML elements specified the Accept
   header in HTTP [RFC2616].

      Content-Type: application/rdap

   Clients MAY use a generic media type for the desired data format of
   the registry response
   documents to be absent from (e.g. "application/json"), but servers SHOULD respond
   with the most appropriate media type (e.g. "application/rdap").  In
   other words, a response as no XML element listed is
   required client may use "application/json" to appear in express that it
   desires JSON or "application/rdap" to express that it desires RDAP
   specific JSON, but the response.

8.  Common Error Response Body

   As specified in Section 5, some non-answer responses may return
   entity bodies server would respond with information that could be more descriptive.

   The basic structure "application/rdap".

4.2.  Query Parameters

   Servers SHOULD ignore unknown query parameters.  Use of that response unknown query
   parameters for cache-busting is described in Appendix A.

5.  Types of HTTP Response

   This section describes the various types of responses a data class containing an
   error code number (corresponding server may
   send to the a client.  While no standard HTTP response code) followed
   by a string named "title" followed by an array of strings named
   "description".

   This code is an example of the JSON version of forbidden
   in usage, at a minimum clients SHOULD understand the common response body.

     {
       "errorCode": 418
       "title": "Your beverage choice is not available",
       "description": [
         "I know coffee has more ummppphhh.",
         "But I cannot provide." ]
     }

                                 Figure 7

   This codes
   described in this section.  It is an example of the XML version expected that usage of the common response body.

     <response>
         <errorCode>418</errorCode>
         <title>Your beverage choice is
   codes and types for this application not available</title>
         <description>I know coffee defined here will be
   described in subsequent documents.

5.1.  Positive Answers

   If a server has more ummppphhh.</description>
         <description>But I cannot provide.</description>
     </response>

                                 Figure 8

   The media type for the JSON structure is "application/
   rdap_error+json" information requested by the client and wishes to
   respond to the media type for client with the XML document is
   "application/rdap_error+xml".  Conformance information according to this specification is
   considered its policies,
   it SHOULD encode the answer in the format most appropriate according
   to be level 0 the standard and defined rules for both media types.

   A client MAY simply use processing the HTTP response code as the server is not
   required to include error data Accept
   header, and return that answer in the response body.  However, if body of a
   client 200 response.

5.2.  Redirects

   If a server wishes to parse inform a client that the error data, answer to a given
   query can be found elsewhere, it SHOULD first check that return either a 301 or a 307
   response code and an HTTP URL in the
   Content-Type header contains Location: header.  The client is
   expected to issue a subsequent query using the appropriate media type.

9.  Common Data Structures

   This section defines two common data structures given URL without any
   processing of the URL.  In other words, the server is to be used by
   DNRD-AP, NRRD-AP, hand back a
   complete URL and other RD-AP protocols.  As such, the names
   identifying these data structures are client should not have to be redefined by any
   registry specific RD-AP specifications.  Each of these datatypes MAY
   appear within any other data object of a response, but transform the intended
   purpose is that they will be mostly used in URL to
   follow it.

   A server SHOULD use a 301 response to inform the top-most data object client of a response.

   The first data structure is named "rdapConformance"
   permanent move and is simply a 307 response otherwise.  For this application,
   such an
   array example of strings, each providing a hint as to the specifications used
   in permanent move might be a top level domain (TLD)
   operator informing a client the construction of information being sought can be found
   with another TLD operator (i.e. a query for the response.

   An example rdapConformance data structure.

     "rdapConformance" : [
       "nrrdap_level_0"
     ]

                                 Figure 9

   The second data structure is named "notices" and domain bar in
   foo.example is an array of
   "notice" objects.  Each "notice" object contains found at http://foo.example/domain/bar).

5.3.  Negative Answers

   If a "title" string
   representing the title of server wishes to respond that it has no information regarding
   the notice object, an array of strings
   named "description" for query, it SHOULD return a 404 response code.  Optionally, it MAY
   include additional information regarding the purposes of conveying any descriptive
   text about negative answer in the notice, and
   HTTP entity body.

5.4.  Malformed Queries

   If a "uri" string holding server receives a URI referencing query which it cannot understand, it SHOULD
   return a
   service that may provide 400 response code.  Optionally, it MAY include additional
   information about the notice.

   An exmaple of regarding this negative answer in the notices HTTP entity body.

6.  Extensibility

   For extensibility purposes, this document defines an IANA registry
   for prefixes used in JSON [RFC4627] data structure.

     "notices" : [
       "notice" : {
         "title" : "Terms of Use",
         "description" : [
           "This service is subject to The Registry serialization and URI path
   segments (see Section 7).

   Prefixes and identifiers SHOULD only consist of the Moons",
           "terms of service."
         ],
         "uri" : "http://example.com/our-terms-of-use"
       }
     ]

                                 Figure 10

   This is an example response with alphabetic ASCII
   characters A through Z in both rdapConformance uppercase and notices
   embedded.

     {
       "rdapConformance" : [
         "nrrdap_level_0"
       ]
       "notices" : [
         "notice" : {
           "title" : "Content Redacted",
           "description" : [
             "Without full authorization, content has been redacted.",
             "Sorry, dude!"
           ],
           "uri" : "http://example.com/our-redaction-policies"
         }
       ]
       "startAddress" : "10.0.0.0",
       "endAddress" : "10.0.0.255",
       "remarks" : [
         "she sells seas shells",
         "down by lowercase, the numerical
   digits 0 through 9, underscore characters, and SHOULD NOT begin with
   an underscore character, numerical digit or the seashore"
       ],
       "uris" : [
         {
           "type" : "source",
           "uri" : "http://whois-rws.net/network/xxxx"
         },
         {
           "type" : "parent",
           "uri" : "http://whois-rws.net/network/yyyy"
         }
       ]
     }

                                 Figure 11

10.  Common Datatypes

   This section characters "xml".
   The following describes common data types found in Internet
   registries, the purpose being production of JSON names in ABNF
   [RFC5234].

   ABNF for JSON names

     name = ALPHA *( ALPHA / DIGIT / "_" )

                                 Figure 1

   This restriction is a common and normalized list union of
   normative references to other specifications to be used by multiple
   RD-AP applications.  Unless otherwise stated by the response
   specification of an Internet registry Ruby programming language
   identifier syntax and the XML element name syntax and has two
   purposes.  First, client implementers using this specification modern programming
   languages such as a
   basis, the data types can assume Ruby or Java may use libraries that automatically
   promote JSON names to be as follows:

   1.  IPv4 addresses - [RFC0791]

   2.  IPv6 addresses - [RFC5952]

   3.  country code - [ISO.3166.1988]

   4.  domain name - [RFC4343]

   5.  email address - [RFC5322]

   6.  date first order object attributes or members.
   Second, a clean mapping between JSON and time strings - [RFC3339]

11. XML is easy to accomplish
   using these rules.

7.  IANA Considerations

11.1.  IANA Registry for RDAP Extensions

   This specification proposes an IANA registry for RDAP extensions.
   The purpose of this registry is to ensure uniqueness of extension
   identifier.
   identifiers.  The extension identifier is used as prefix in JSON
   names and as a prefix of path segments in RDAP URLs.

   The production rule for JSON names in response these identifiers is specified in Section 6.2. 6.

   In accordance with RFC5226, the IANA policy for assigning new values
   shall be Specification Required: values and their meanings must be
   documented in an RFC or in some other permanent and readily available
   reference, in sufficient detail that interoperability between
   independent implementations is possible.

   The following is a preliminary template for an RDAP extension
   registration:

      Extension identifier: the identifier of the extension

      Registry operator: the name of the registry operator

      Published specification: RFC number, bibliographical reference or
      URL to a permenant permanent and readily available specification

      Person & email address to contact for further information: The
      names and email addresses of individuals for contact regarding
      this registry entry

      Intended usage: brief reasons for this registry entry

   The following is an example of a regstration registration in the RDAP extension
   registry:

      Extension identifier: lunarNic

      Registry operator: The Registry of the Moon, LLC

      Published specification: http://www.example/moon_apis/rdap

      Person & email address to contact for further information:
      Professor Bernardo de la Paz <berny&moon.example>

      Intended usage: COMMON

11.2.  Registration of RDAP Media Type for JSON

   This specification registers the "application/rdap+json" media type.

      Type name: application

      Subtype name: rdap+json

      Required parameters: n/a

      Optional parameters: level

      Encoding considerations: n/a

      Security considerations: n/a

      Interoperability considerations: n/a

      Published specification: [[ this document ]]

      Applications that use this media type: RDAP

      Additional information: n/a

      Person & email address to contact for further information: Andy
      Newton &andy@hxr.us&

      Intended usage: COMMON

      Restrictions on usage: none

      Author: Andy Newton

      Change controller: IETF

11.3.  Registration of RDAP Media Type for XML

   This specification registers the "application/rdap+xml" media type.

      Type name: application

      Subtype name: rdap+xml

      Required parameters: n/a

      Optional parameters: level
      Encoding considerations: n/a

      Security considerations: n/a

      Interoperability considerations: n/a

      Published specification: [[ this document ]]

      Applications that use this media type: RDAP

      Additional information: n/a

      Person & email address to contact for further information: Andy
      Newton &andy@hxr.us& <berny@moon.example>

      Intended usage: COMMON

      Restrictions on usage: none

      Author: Andy Newton

      Change controller: IETF

12.

8.  Internationalization Considerations

12.1.

8.1.  URIs vs and IRIs

   Clients MAY use IRIs as they see fit, but MUST transform them to URIs
   [RFC3986] for interaction with RD-AP RDAP servers.  RD-AP  RDAP servers MUST use
   URIs in all responses, all responses, and clients MAY transform these URIs to IRIs.

8.2.  Language Identifiers in Queries and Responses

   Depending on the data format of the response, servers MAY include
   data in character sets other than ASCII and languages other than
   English (the data format will most likely be in Unicode and almost
   certainly languages other than English will be encountered).  Under
   most scenarios, clients requesting data will not signal that the data
   be returned in a particular language or script.  On the other hand,
   when servers return data and have knowledge that the data is in a
   language or script, the data should be annotated with language
   identifiers thus allowing clients MAY transform these URIs to IRIs.

12.2.  Character Encoding

   The default text encoding for JSON process and XML responses display the data
   accordingly.

   A language identifier in the response is specified in RD-AP section 5.3 of
   [draft-ietf-weirds-json-response].  It is used to indicate the
   language/script of the response data.  It is possible that
   registration data is
   UTF-8, stored in several different languages and all
   returned in a single response.  Data portion of different language
   types SHOULD be tagged with its corresponding identifier if known.

8.3.  Language Identifiers in HTTP Headers

   Given the description of the use of language identifiers in
   Section 8.2, unless otherwise specified servers SHOULD ignore the
   HTTP [RFC2616] Accept-Language header when formulating responses.

   However, servers and clients MUST support UTF-8.  Servers and
   clients MAY optionally support other character encodings.

13. return language identifiers in the Content-
   Language header so as to inform clients of the intended language of
   HTTP layer messages.

9.  Normative References

   [draft-kucherawy-weirds-requirements]
              Kucherawy, M., "Requirements For Internet Registry
              Services", Work in progress: Internet
              Drafts draft-kucherawy-weirds-requirements-04.txt,
              April 2011.

   [draft-ietf-weirds-json-response]
              Newton, A. and S. Hollenbeck, "JSON Responses for the
              Registration Data Access Protocol (RDAP)", Work in
              progress: Internet
              Drafts draft-ietf-weirds-json-response-01.txt,
              December 2012.

   [SAC-051]  Piscitello, D., Ed., "SSAC Report on Domain Name WHOIS
              Terminology and Structure", September 2011.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC4627]  Crockford, D., "The application/json Media Type for
              JavaScript Object Notation (JSON)", RFC 4627, July 2006.

   [RFC3339]  Klyne, G., Ed. and C. Newman, "Date and Time on the
              Internet: Timestamps", RFC 3339, July 2002.

   [RFC4034]  Arends, R., Austein, R., Larson, M., Massey, D., and S.
              Rose, "Resource Records for the DNS Security Extensions",
              RFC 4034, March 2005.

   [RFC0791]  Postel, J., "Internet Protocol", STD 5, RFC 791,
              September 1981.

   [RFC5952]  Kawamura, S. and M. Kawashima, "A Recommendation for IPv6
              Address Text Representation", RFC 5952, August 2010.

   [ISO.3166.1988]
              International Organization for Standardization, "Codes for
              the representation of names of countries, 3rd edition",
              ISO Standard 3166, August 1988.

   [RFC5396]  Huston, G. and G. Michaelson, "Textual Representation of
              Autonomous System (AS) Numbers", RFC 5396, December 2008.

   [RFC4343]  Eastlake, D., "Domain Name System (DNS) Case Insensitivity
              Clarification", RFC 4343, January 2006.

   [RFC3986]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
              Resource Identifier (URI): Generic Syntax", STD 66,
              RFC 3986, January 2005.

   [RFC5322]  Resnick, P., Ed., "Internet Message Format", RFC 5322,
              October 2008.

   [RFC2616]  Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
              Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext
              Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.

   [RFC5234]  Crocker, D. and P. Overell, "Augmented BNF for Syntax
              Specifications: ABNF", STD 68, RFC 5234, January 2008.

Appendix A.  Cache Busting

   To overcome issues with misbehaving HTTP [RFC2616] cache
   infrastructure, clients may MAY use the an adhoc and improbably used query
   parameter with a random value of their choosing.  As Section 4.2
   instructs servers to ignore unknown parameters, this is unlikely to
   have any known side effects.

   An example of using an unknown query parameter to bust caches:

     http://example.com/ip/192.0.2.0?__fuhgetaboutit=xyz123

   Use of an unknown parameter to overcome misbehaving caches is not
   part of any specification and is offered here for informational
   purposes.

Appendix B.  Changelog

   Initial WG -00:  Updated to working group document 2012-September-20

   -01

      *  Updated for the sections moved to the JSON responses draft.

      *  Simplified media type, removed "level" parameter.

      *  Updated 2119 language and added boilerplate.

      *  In section 1, noted that redirects can go to redirect servers
         as well.

      *  Added Section 8.2 and Section 8.3.

Authors' Addresses

   Andrew Lee Newton
   American Registry for Internet Numbers
   3635 Concorde Parkway
   Chantilly, VA  20151
   US

   Email: andy@arin.net
   URI:   http://www.arin.net

   Byron J. Ellacott
   Asia Pacific Network Information Center
   6 Cordelia Street
   South Brisbane  QLD 4101
   Australia

   Email: bje@apnic.net
   URI:   http://www.apnic.net

   Ning Kong
   China Internet Network Information Center
   4 South 4th Street, Zhongguancun, Haidian District
   Beijing  100190
   China

   Phone: +86 10 5881 3147
   Email: nkong@cnnic.cn