Network Working Group                                          A. Newton
Internet-Draft                                                      ARIN
Intended status: Standards Track                           S. Hollenbeck
Expires: December 14, 2013 February 17, 2014                                 Verisign Labs
                                                           June 12,
                                                         August 16, 2013

             Registration Data Access Protocol Lookup Query Format
                    draft-ietf-weirds-rdap-query-05
                    draft-ietf-weirds-rdap-query-06

Abstract

   This document describes uniform patterns to construct HTTP URLs that
   may be used to retrieve registration information from registries
   (including both Regional Internet Registries (RIRs) and Domain Name
   Registries (DNRs)) using "RESTful" web access patterns.

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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   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
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   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on December 14, 2013. February 17, 2014.

Copyright Notice

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   document authors.  All rights reserved.

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Table of Contents

   1.  Conventions Used in This Document . . . . . . . . . . . . . .   2
     1.1.  Acronyms and Abbreviations  . . . . . . . . . . . . . . .   2
   2.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2   3
   3.  Path Segment Specification  . . . . . . . . . . . . . . . . .   4
     3.1.  IP Network  Lookup Path Segment Specification . . . . . . . . . . . .   4
     3.2.  Autonomous System
       3.1.1.  IP Network Path Segment Specification . . . . . .   5
     3.3.  Domain . .   4
       3.1.2.  Autonomous System Path Segment Specification  . . . .   5
       3.1.3.  Domain Path Segment Specification . . . . . . . . . .   6
     3.4.
       3.1.4.  Name Server Path Segment Specification  . . . . . . . . .   6
     3.5.
       3.1.5.  Entity Path Segment Specification . . . . . . . . . .   7
       3.1.6.  Help Path Segment Specification . . . . . . . . . . .   7
     3.6.  Help
     3.2.  Search Path Segment Specification . . . . . . . . . . . .   8
       3.2.1.  Domain Search . . .   7
   4.  Extensibility . . . . . . . . . . . . . . . . .   8
       3.2.2.  Name Server Search  . . . . . . . . . . . . . . . . .   8
       3.2.3.  Entity Search . . . . . . . . . . . . . . . . . . . .   9
   4.  Search Processing . . . . . . . . . . . . . . . . . . . . . .   9
   5.  Extensibility . . . . . . . . . . . . . . . . . . . . . . . .  10
   6.  Internationalization Considerations . . . . . . . . . . . . .   8
   6.  10
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   8
   7.  11
   8.  Security Considerations . . . . . . . . . . . . . . . . . . .   8
   8.  11
   9.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .   8
   9.  11
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . .   9
     9.1.  12
     10.1.  Normative References . . . . . . . . . . . . . . . . . .   9
     9.2.  12
     10.2.  Informative References . . . . . . . . . . . . . . . . .  10  13
   Appendix A.  Path Segment Specification for Search Queries  . . .  11
   Appendix B.  Change Log . . . . . . . . . . . . . . . . . . . . .  11  14
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  12  14

1.  Conventions Used in This Document

   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 RFC 2119 [RFC2119].

1.1.  Acronyms and Abbreviations

      IDN: Internationalized Domain Name
      IDNA: Internationalized Domain Names in Applications
      DNR: Domain Name Registry
      RDAP: Registration Data Access Protocol
      REST: Representational State Transfer State Transfer.  The term
      was first described in a doctoral dissertation [REST].
      RESTful: an adjective that describes a service using HTTP and the
      principles of REST.
      RIR: Regional Internet Registry

2.  Introduction

   This document describes a specification for querying registration
   data using a RESTful web service and uniform query patterns.  The
   service is implemented using the Hypertext Transfer Protocol (HTTP)
   [RFC2616].

   The protocol described in this specification is intended to address
   deficiencies with the WHOIS protocol [RFC3912] that have been
   identified over time, including:

   o  Lack of standardized command structures,
   o  lack of standardized output and error structures,
   o  lack of support for internationalization and localization, and
   o  lack of support for user identification, authentication, and
      access control.

   The patterns described in this document purposefully do not encompass
   all of the methods employed in the WHOIS and RESTful web services of
   all of the RIRs and DNRs.  The intent of the patterns described here
   are to enable lookups queries of:

   o  networks by IP address,
   o  autonomous system numbers by number,
   o  reverse DNS meta-data by domain,
   o  name servers by name,
   o  registrars by name, and
   o  entities (such as contacts) by identifier.

   It is envisioned that each registry will continue to maintain NICNAME
   /WHOIS and/or RESTful web services specific to their needs and those
   of their constituencies, and the information retrieved through the
   patterns described here may reference such services.

   Likewise, future IETF standards may add additional patterns for
   additional query types (for example, "/domains" for a domain search
   query).  And Section 4 defines a types.  A simple pattern namespacing scheme is
   described in Section 5 to accomodate custom extensions that will not
   interfere with the patterns defined in this document or patterns
   defined in future IETF standards.

   WHOIS services, in general, are read-only services.  Therefore URL
   [RFC3986] patterns specified in this document are only applicable to
   the HTTP [RFC2616] GET and HEAD methods.

   This document does not describe the results or entities returned from
   issuing the described URLs with an HTTP GET.  It  JSON [RFC4627] result
   formatting and processing is envisioned that
   other documents will describe these entities described in various serialization
   formats, such as JavaScript Object Notation (JSON, [RFC4627]).
   [I-D.ietf-weirds-json-response].

   Additionally, resource management, provisioning and update functions
   are out of scope for this document.  Registries have various and
   divergent methods covering these functions, and it is unlikely a
   uniform approach for these functions will ever be possible.

   HTTP contains mechanisms for servers to authenticate clients and for
   clients to authenticate servers (from which authorization schemes may
   be built) so such mechanisms are not described in this document.
   Policy, provisioning, and processing of authentication and
   authorization are out-of-scope for this document as deployments will
   have to make choices based on local criteria.  Specified
   authentication mechanisms MUST use HTTP.

3.  Path Segment Specification

   The uniform patterns start with a base URL [RFC3986] specified by
   each registry or any other service provider offering this service.
   The base URL is followed by a resource-type-specific path segment.
   The base URL may contain its own path segments (e.g. http://
   example.com/... or http://example.com/restful-WHOIS/... http://example.com/rdap/... ).  The characters
   used to form a path segment are limited to those that can be used to
   form a URI as specified in RFC 3986 [RFC3986].

3.1.  Lookup Path Segment Specification

   The resource type path segments for exact match lookup are:

   o  'ip': Used to identify IP networks and associated data referenced
      using either an IPv4 or IPv6 address.
   o  'autnum': Autonomous Used to identify autonomous system registrations and
      associated data referenced using an AS Plain autonomous system
      number.
   o  'domain': Reverse Used to identify reverse DNS (RIR) or domain name (DNR)
      information and associated data referenced using a fully-qualified
      domain name.
   o  'nameserver': Used to identify a name server information query. query
      using a host name.
   o  'entity': Used to identify an entity information query.

3.1. query using a
      string identifier.

3.1.1.  IP Network Path Segment Specification

   Syntax: ip/<IP address> or ip/<CIDR prefix>/<CIDR length>

   Queries for information about IP networks are of the form /ip/XXX/...
   or /ip/XXX/YY/...  where the path segment following 'ip' is either an
   IPv4 [RFC1166] or IPv6 [RFC5952] address (i.e. XXX) or an IPv4 or
   IPv6 CIDR [RFC4632] notation address block (i.e. XXX/YY).

   Semantically, the simpler form using the address can be thought of as
   a CIDR block with a bitmask length of 32 for IPv4 and a bitmask
   length of 128 for IPv6.  A given specific address or CIDR may fall
   within multiple IP networks in a hierarchy of networks, therefore
   this query targets the "most-specific" or smallest IP network which
   completely encompasses it in a hierarchy of IP networks.

   The IPv4 and IPv6 address formats supported in this query are
   described in section 3.2.2 of [RFC3986], as IPv4address and
   IPv6address ABNF definitions.  Any valid IPv6 text address format
   [RFC4291] can be used, compressed or not compressed.  The restricted
   rules to write a text representation of an IPv6 address [RFC5952] are
   not mandatory.  However, the zone id [RFC4007] is not appropriate in
   this context and therefore prohibited.

   This is an example URL for the most specific network containing
   192.0.2.0:

   /ip/192.0.2.0

   This is an example of a URL the most specific network containing
   192.0.2.0/24:

   /ip/192.0.2.0/24

   This is an example URL for the most specific network containing
   2001:db8:1:1::1:

   /ip/2001:db8:1:1::1

3.2.

3.1.2.  Autonomous System Path Segment Specification

   Syntax: autnum/<autonomous system number>

   Queries for information regarding autonomous system number
   registrations are of the form /autnum/XXX/... where XXX is an asplain
   autonomous system number [RFC5396].  In some registries, registration
   of autonomous system numbers is done on an individual number basis,
   while other registries may register blocks of autonomous system
   numbers.  The semantics of this query are such that if a number falls
   within a range of registered blocks, the target of the query is the
   block registration, and that individual number registrations are
   considered a block of numbers with a size of 1.

   For example, to find information on autonomous system number 65551,
   the following path would be used:

   /autnum/65551
   The following path would be used to find information on 4-byte
   autonomous system number 65538:

   /autnum/65538

3.3.

3.1.3.  Domain Path Segment Specification

   Syntax: domain/<domain name>

   Queries for domain information are of the form /domain/XXXX/...,
   where XXXX is a fully-qualified domain name [RFC4343] in either the
   in-addr.arpa or ip6.arpa zones (for RIRs) or a fully-qualified domain
   name in a zone administered by the server operator (for DNRs).
   Internationalized domain names represented in either A-label or
   U-label format [RFC5890] are also valid domain names.  IDN labels
   SHOULD NOT be represented as a mixture of A-labels and U-labels.

   If the client sends the server an IDN in U-label format, servers that
   support IDNs MUST convert the IDN into A-label format and perform
   IDNA processing as specified in RFC 5891 [RFC5891].  The server
   should perform an exact match lookup using the A-label.

   The following path would be used to find information describing the
   zone serving the network 192.0.2/24:

   /domain/2.0.192.in-addr.arpa

   The following path would be used to find information describing the
   zone serving the network 2001:db8:1::/48:

   /domain/1.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa

   The following path would be used to find information for the
   example.com domain name:

   /domain/example.com

   The following path would be used to find information for the
   xn--xemple-9ua.example IDN:

   /domain/xn--xemple-9ua.example

3.4.

3.1.4.  Name Server Path Segment Specification

   Syntax: nameserver/<name server name>

   The <name server name> parameter represents a fully qualified name as
   specified in RFC 952 [RFC0952] and RFC 1123 [RFC1123].

   Internationalized names represented in either A-label or U-label
   format [RFC5890] are also valid name server names.  IDN labels SHOULD
   NOT be represented as a mixture of A-labels and U-labels.

   If the client sends the server an IDN in U-label format, servers that
   support IDNs MUST convert the IDN into A-label format and perform
   IDNA processing as specified in RFC 5891 [RFC5891].  The server
   should perform an exact match lookup using the A-label.

   The following path would be used to find information for the
   ns1.example.com name server:

   /nameserver/ns1.example.com

   The following path would be used to find information for the
   ns1.xn--xemple-9ua.example name server:

   /nameserver/ns1.xn--xemple-9ua.example

3.5.

3.1.5.  Entity Path Segment Specification

   Syntax: entity/<handle>

   The <handle> parameter represents an entity (such as a contact,
   registrant, or registrar) identifier.  For example, for some DNRs
   contact identifiers are specified in RFC 5730 [RFC5730] and RFC 5733
   [RFC5733].

   The following path would be used to find information for the entity
   associated with handle CID-4005:

   /entity/CID-4005

3.6.

3.1.6.  Help Path Segment Specification

   Syntax: help

   The help path segment can be used to request helpful information
   (command syntax, terms of service, privacy policy, rate limiting
   policy, supported authentication methods, supported extensions,
   technical support contact, etc.) from an RDAP server.  The response
   to "help" should provide basic information that a client needs to
   successfully use the service.  The following path would be used to
   return "help" information:

   /help

4.

3.2.  Search Path Segment Specification

   The resource type path segments for search are:

   o  'domains': Used to identify a domain name information search using
      a pattern to match a fully-qualified domain name.
   o  'nameservers': Used to identify a name server information search
      using a pattern to match a host name.
   o  'entities': Used to identify an entity information search using a
      pattern to match a string identifier.

   RDAP search path segments are formed using a concatenation of the
   plural form of the object being searched for, a forward slash
   character ('/', ASCII value 0x002F), and an HTTP query string.  The
   HTTP query string is formed using a concatenation of the question
   mark character ('?', ASCII value 0x003F), the JSON object value
   associated with the object being searched for, the equal sign
   character ('=', ASCII value 0x003D), and the search pattern.  For the
   domain and entity objects described in this document the plural
   object forms are "domains" and "entities".

3.2.1.  Domain Search

   Syntax: domains/?ldhName=<domain search pattern>

   Searches for domain information are of the form /domains/
   ?ldhName=XXXX, where XXXX is a search pattern representing a domain
   name in "letters, digits, hyphen" format [RFC5890] in a zone
   administered by the server operator of a DNR.  The following path
   would be used to find DNR information for domain names matching the
   "example*.com" pattern:

   /domains/?ldhName=example*.com

   Internationalized Domain Names (IDNs) in U-label format [RFC5890] can
   also be used as search patterns (see Section 4).  Searches for these
   names are of the form /domains/?unicodeName=XXXX, where XXXX is a
   search pattern representing a domain name in U-label format
   [RFC5890].

3.2.2.  Name Server Search

   Syntax: nameservers/?ldhName=<nameserver search pattern>

   Searches for name server information are of the form /nameservers/
   ?ldhName=XXXX, where XXXX is a search pattern representing a host
   name in "letters, digits, hyphen" format [RFC5890] in a zone
   administered by the server operator of a DNR.  The following path
   would be used to find DNR information for name server names matching
   the "ns1.example*.com" pattern:

   /nameservers/?ldhName=ns1.example*.com

   Internationalized name server names in U-label format [RFC5890] can
   also be used as search patterns (see Section 4).  Searches for these
   names are of the form /nameservers/?unicodeName=XXXX, where XXXX is a
   search pattern representing a name server name in U-label format
   [RFC5890].

3.2.3.  Entity Search

   Syntax: entities/?fn=<entity search pattern>

   Searches for entity information are of the form /entities/?fn=XXXX,
   where XXXX is a search pattern representing an entity name as
   specified in Section 7.1 of [I-D.ietf-weirds-json-response].  The
   following path would be used to find information for entity names
   matching the "Bobby Joe*" pattern.

   /entities/?fn=Bobby%20Joe*

   URLs MUST be properly encoded according to the rules of [RFC3986].
   In the example above, "Bobby Joe*" is encoded to "Bobby%20Joe*".

4.  Search Processing

   Partial string searching uses the asterisk ('*', ASCII value 0x002A)
   character to match zero or more trailing characters.  Additional
   pattern matching processing is beyond the scope of this
   specification.

   If a server receives a search request but cannot process the request
   because it does not support a particular style of partial match
   searching, it SHOULD return an HTTP 422 [RFC4918] error.  When
   returning a 422 error, the server MAY also return an error response
   body as specified in Section 12 of [I-D.ietf-weirds-json-response] if
   the requested media type is one that is specified in
   [I-D.ietf-weirds-using-http].

   Because Unicode characters may be combined with another Unicode
   character or characters, partial matching is not feasible across
   combinations of Unicode characters.  Servers SHOULD NOT partially
   match combinations of Unicode characters where a Unicode character
   may be legally combined with another Unicode character or characters.
   Clients MUST NOT issue a partial match search of Unicode characters
   where a Unicode character may be legally combined with another
   Unicode character or characters.  Partial match searches with
   incomplete combinations of characters where a character must be
   combined with another character or characters are invalid.  Partial
   match searches with characters that may be combined with another
   character or characters are to be considered non-combined characters
   (that is, if character x maybe combined with character y but
   character y is not submitted in the search string then character x is
   a complete character and no combinations of character x are to
   searched).

   Because Unicode characters may be combined with another Unicode
   character or characters, partial matching requires that a server
   maintain a list of valid character combinations to be considered a
   match.  When comparing DNS U-labels, servers SHOULD use the code
   points specified in [RFC5892] to determine partial matches.  When
   comparing entity names, servers SHOULD use the normalization rules
   and code points specified by [I-D.ietf-precis-nickname] to determine
   partial matches.

   Clients SHOULD NOT submit search requests with partial matching for
   DNS A-labels starting with 'xn--'.  A-labels of this type represent
   an encoding that can only be reconstructed properly when the label is
   complete.

5.  Extensibility

   This document describes path segment specifications for a limited
   number of objects commonly registered in both RIRs and DNRs.  It does
   not attempt to describe path segments for all of the objects
   registered in all registries.  Custom path segments can be created
   for objects not specified here using the process described in
   Section TBD of "Using HTTP for RESTful Whois Services by Internet
   Registries" [I-D.ietf-weirds-using-http].

   Custom path segments can be created by prefixing the segment with a
   unique identifier followed by an underscore character (0x5F).  For
   example, a custom entity path segment could be created by prefixing
   "entity" with "custom_", producing "custom_entity".  Servers MUST
   return an appropriate failure status code for a request with an
   unrecognized path segment.

5.

6.  Internationalization Considerations

   There is value in supporting the ability to submit either a U-label
   (Unicode form of an IDN label) or an A-label (ASCII form of an IDN
   label) as a query argument to an RDAP service.  Clients capable of
   processing non-ASCII characters may prefer a U-label since this is
   more visually recognizable and familiar than A-label strings, but
   clients using programmatic interfaces might find it easier to submit
   and display A-labels if they are unable to input U-labels with their
   keyboard configuration.  Both query forms are acceptable.

   Internationalized domain and name server names can contain character
   variants and variant labels as described in RFC 4290 [RFC4290].
   Clients that support queries for internationalized domain and name
   server names MUST accept service provider responses that describe
   variants as specified in "JSON Responses for the Registration Data
   Access Protocol" [I-D.ietf-weirds-json-response].

6.

7.  IANA Considerations

   This document does not specify any IANA actions.

7.

8.  Security Considerations

   Security services for the operations specified in this document are
   described in "Security Services for the Registration Data Access
   Protocol" [I-D.ietf-weirds-rdap-sec].

8.

   Search functionality typically requires more server resources (such
   as memory, CPU cycles, and network bandwidth) when compared to basic
   lookup functionality.  This increases the risk of server resource
   exhaustion and subsequent denial of service due to abuse.  This risk
   can be mitigated by developing and implementing controls to restrict
   search functionality to identified and authorized clients.  If those
   clients behave badly, their search privileges can be suspended or
   revoked.  Rate limiting as described in Section 5.5 of "Using the
   Registration Data Access Protocol (RDAP) with HTTP"
   [I-D.ietf-weirds-using-http] can also be used to control the rate of
   received search requests.  Server operators can also reduce their
   risk by restricting the amount of information returned in response to
   a search request.

9.  Acknowledgements

   This document is derived from original work on RIR query formats
   developed by Byron J. Ellacott of APNIC, Arturo L. Servin of LACNIC,
   Kaveh Ranjbar of the RIPE NCC, and Andrew L. Newton of ARIN.
   Additionally, this document incorporates DNR query formats originally
   described by Francisco Arias and Steve Sheng of ICANN and Scott
   Hollenbeck of Verisign.

   The authors would like to acknowledge the following individuals for
   their contributions to this document: Francisco Arias, Marc Blanchet,
   Ernie Dainow, Jean-Philippe Dionne, Behnam Esfahbod, Edward Lewis,
   and John Levine.

9.

10.  References

9.1.

10.1.  Normative References

   [I-D.ietf-precis-nickname]
              Saint-Andre, P., "Preparation and Comparison of
              Nicknames", draft-ietf-precis-nickname-06 (work in
              progress), July 2013.

   [I-D.ietf-weirds-json-response]
              Newton, A. and S. Hollenbeck, "JSON Responses for the
              Registration Data Access Protocol (RDAP)", draft-ietf-
              weirds-json-response-04 (work in progress), June 2013.

   [I-D.ietf-weirds-rdap-sec]
              Hollenbeck, S. and N. Kong, "Security Services for the
              Registration Data Access Protocol", draft-ietf-weirds-
              rdap-sec-04 (work in progress), June 2013.

   [I-D.ietf-weirds-using-http]
              Newton, A., Ellacott, B., and N. Kong, "HTTP usage in the
              Registration Data Access Protocol (RDAP)", draft-ietf-
              weirds-using-http-05
              weirds-using-http-07 (work in progress), May July 2013.

   [RFC0952]  Harrenstien, K., Stahl, M., and E. Feinler, "DoD Internet
              host table specification", RFC 952, October 1985.

   [RFC1123]  Braden, R., "Requirements for Internet Hosts - Application
              and Support", STD 3, RFC 1123, October 1989.

   [RFC1166]  Kirkpatrick, S., Stahl, M., and M. Recker, "Internet
              numbers", RFC 1166, July 1990.

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

   [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.

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

   [RFC4290]  Klensin, J., "Suggested Practices for Registration of
              Internationalized Domain Names (IDN)", RFC 4290, December
              2005.

   [RFC4291]  Hinden, R. and S. Deering, "IP Version 6 Addressing
              Architecture", RFC 4291, February 2006.

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

   [RFC4632]  Fuller, V. and T. Li, "Classless Inter-domain Routing
              (CIDR): The Internet Address Assignment and Aggregation
              Plan", BCP 122, RFC 4632, August 2006.

   [RFC4918]  Dusseault, L., "HTTP Extensions for Web Distributed
              Authoring and Versioning (WebDAV)", RFC 4918, June 2007.

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

   [RFC5730]  Hollenbeck, S., "Extensible Provisioning Protocol (EPP)",
              STD 69, RFC 5730, August 2009.

   [RFC5733]  Hollenbeck, S., "Extensible Provisioning Protocol (EPP)
              Contact Mapping", STD 69, RFC 5733, August 2009.

   [RFC5890]  Klensin, J., "Internationalized Domain Names for
              Applications (IDNA): Definitions and Document Framework",
              RFC 5890, August 2010.

   [RFC5891]  Klensin, J., "Internationalized Domain Names in
              Applications (IDNA): Protocol", RFC 5891, August 2010.

   [RFC5892]  Faltstrom, P., "The Unicode Code Points and
              Internationalized Domain Names for Applications (IDNA)",
              RFC 5892, August 2010.

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

9.2.

10.2.  Informative References

   [REST]     Fielding, R. and R. Taylor, "Principled Design of the
              Modern Web Architecture", ACM Transactions on Internet
              Technology Vol. 2, No. 2, May 2002.

   [RFC3912]  Daigle, L., "WHOIS Protocol Specification", RFC 3912,
              September 2004.

   [RFC4007]  Deering, S., Haberman, B., Jinmei, T., Nordmark, E., and
              B. Zill, "IPv6 Scoped Address Architecture", RFC 4007,
              March 2005.

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

Appendix A.  Path Segment Specification for Search Queries

   All of the path segments described in this document identify patterns
   for exact-match lookups of data elements.  We have explicitly omitted
   specifications for search queries in the interest of first focusing
   on more basic protocol operations.  Once we understand how exact-
   match queries will work we will attempt to define specifications for
   search queries in other documents.

   It is important to note that there are already multiple
   implementations of RESTful RDAP-like prototypes that provide search
   capabilities.  For example:

   ARIN:   The American Registry for Internet Numbers (ARIN) has
      published an API [1] (see Section 4.4.2) that describes using
      plural forms of path segment identifiers (e.g. "domains") and
      Matrix URIs [2] to indicate that a client is requesting a list of
      values when searching for RIR registration data.  A prototype
      service [3] that implements this API is up and running.
   Verisign:   Verisign has deployed a prototype service [4] that
      implements searches for DNR registration data using HTML query
      strings (e.g. "?_PRE") to identify search parameters.  For
      example, "http://dnrd.verisignlabs.com/dnrd-ap/domain/
      verisign?_PRE" performs a search for domain names with a
      "verisign" prefix.

Appendix B.  Change Log

   Initial -00:  Adopted as working group document.
   -01:  Added "Conventions Used in This Document" section.  Added
      normative reference to draft-ietf-weirds-rdap-sec and some
      wrapping text in the Security Considerations section.
   -02:  Removed "unified" from the title.  Rewrote the last paragraph
      of section 2.  Edited the first paragraph of section 3 to more
      clearly note that only one path segement is provided.  Added
      "bitmask" to "length" in section 3.1.  Changed "lowest IP network"
      to "smallest IP network" in section 3.1.  Added "asplain" to the
      description of autonomous system numbers in section 3.2.  Minor
      change from "semantics is" to "semantics are" in section 3.2.
      Changed the last sentence in section 4 to more clearly specify
      error response behavior.  Added acknowledgements.  Added a
      paragraph in the introduction regarding future IETF standards and
      extensibility.
   -03:  Changed 'query' to 'lookup' in document title to better
      describe the 'exact match lookup' purpose of this document.
      Included a multitude of minor additions and clarifications
      provided by Marc Blanchet and Jean-Philippe Dionne.  Modified the
      domain and name server sections to include support for IDN
      U-labels.
   -04:  Updated the domain and name server sections to use .example IDN
      U-labels.  Added text to note that mixed IDN labels SHOULD NOT be
      used.  Fixed broken sentences in Section 5. 6.
   -05:  Added "help" path segment.
   -06:  Added search text and removed or edited old search text.

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
   Scott Hollenbeck
   Verisign Labs
   12061 Bluemont Way
   Reston, VA  20190
   US

   Email: shollenbeck@verisign.com
   URI:   http://www.verisignlabs.com/