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data-event-name="pinnable-header.vector-toc.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-toc.unpin">hide</button> </div> <ul class="vector-toc-contents" id="mw-panel-toc-list"> <li id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">(Top)</div> </a> </li> <li id="toc-X.500_protocols" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#X.500_protocols"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>X.500 protocols</span> </div> </a> <ul id="toc-X.500_protocols-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Transport_Protocols" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Transport_Protocols"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Transport Protocols</span> </div> </a> <ul id="toc-Transport_Protocols-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-X.500_data_models" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#X.500_data_models"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>X.500 data models</span> </div> </a> <ul id="toc-X.500_data_models-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-The_relationship_of_the_X.500_Directory_and_X.509v3_digital_certificates" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#The_relationship_of_the_X.500_Directory_and_X.509v3_digital_certificates"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>The relationship of the X.500 Directory and X.509v3 digital certificates</span> </div> </a> <ul id="toc-The_relationship_of_the_X.500_Directory_and_X.509v3_digital_certificates-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-List_of_X.500_series_standards" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#List_of_X.500_series_standards"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>List of X.500 series standards</span> </div> </a> <ul id="toc-List_of_X.500_series_standards-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Criticism" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Criticism"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Criticism</span> </div> </a> <ul id="toc-Criticism-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> 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<h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">X.500</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. 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lang="cs" hreflang="cs" data-title="X.500" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/X.500" title="X.500 – Danish" lang="da" hreflang="da" data-title="X.500" data-language-autonym="Dansk" data-language-local-name="Danish" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/X.500" title="X.500 – German" lang="de" hreflang="de" data-title="X.500" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/X.500" title="X.500 – Estonian" lang="et" hreflang="et" data-title="X.500" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/X.500" title="X.500 – Spanish" lang="es" hreflang="es" data-title="X.500" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/X.500" title="X.500 – French" lang="fr" hreflang="fr" data-title="X.500" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/X.500" title="X.500 – Korean" lang="ko" hreflang="ko" data-title="X.500" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/X.500" title="X.500 – Italian" lang="it" hreflang="it" data-title="X.500" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/X.500" title="X.500 – Hungarian" lang="hu" hreflang="hu" data-title="X.500" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/X.500" title="X.500 – Dutch" lang="nl" hreflang="nl" data-title="X.500" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/X.500" title="X.500 – Japanese" lang="ja" hreflang="ja" data-title="X.500" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/X.500" title="X.500 – Polish" lang="pl" hreflang="pl" data-title="X.500" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/X.500" title="X.500 – Portuguese" lang="pt" hreflang="pt" data-title="X.500" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/X.500" title="X.500 – Russian" lang="ru" hreflang="ru" data-title="X.500" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/X.500" title="X.500 – Finnish" lang="fi" hreflang="fi" data-title="X.500" data-language-autonym="Suomi" data-language-local-name="Finnish" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/X.500" title="X.500 – Ukrainian" lang="uk" hreflang="uk" data-title="X.500" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-yo mw-list-item"><a href="https://yo.wikipedia.org/wiki/X.500" title="X.500 – Yoruba" lang="yo" hreflang="yo" data-title="X.500" data-language-autonym="Yorùbá" data-language-local-name="Yoruba" class="interlanguage-link-target"><span>Yorùbá</span></a></li><li class="interlanguage-link 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class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Series of computer networking standards covering electronic directory services</div> <p><b>X.500</b> is a series of computer networking standards covering electronic <a href="/wiki/Directory_service" title="Directory service">directory services</a>. The X.500 series was developed by the <a href="/wiki/ITU-T" title="ITU-T">Telecommunication Standardization Sector of the International Telecommunication Union</a> (ITU-T). ITU-T was formerly known as the Consultative Committee for International Telephony and Telegraphy (CCITT). X.500 was first approved in 1988.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> The directory services were developed to support requirements of <a href="/wiki/X.400" title="X.400">X.400</a> electronic mail exchange and name lookup. The <a href="/wiki/International_Organization_for_Standardization" title="International Organization for Standardization">International Organization for Standardization</a> (ISO) and <a href="/wiki/International_Electrotechnical_Commission" title="International Electrotechnical Commission">International Electrotechnical Commission</a> (IEC) were partners in developing the standards, incorporating them into the <a href="/wiki/Open_Systems_Interconnection" class="mw-redirect" title="Open Systems Interconnection">Open Systems Interconnection</a> suite of protocols. <b>ISO/IEC 9594</b> is the corresponding ISO/IEC identification. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="X.500_protocols">X.500 protocols</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=X.500&action=edit&section=1" title="Edit section: X.500 protocols"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The protocols defined by X.500 include: </p> <table class="wikitable"> <caption> </caption> <tbody><tr> <th>Protocol Name </th> <th>Description </th> <th>Defining Specification* </th></tr> <tr> <td>Directory Access Protocol (DAP) </td> <td>"Defines the exchange of requests and outcomes between a DUA and a DSA." <p>This is how a client interacts with the directory system. </p> </td> <td>ITU Recommendation X.511 </td></tr> <tr> <td>Directory System Protocol (DSP) </td> <td>"Defines the exchange of requests and outcomes between two DSAs." <p>This is how two directory servers interact with each other. </p> </td> <td>ITU Recommendation X.518 </td></tr> <tr> <td>Directory Information Shadowing Protocol (DISP) </td> <td>"Defines the exchange of replication information between two DSAs that have established shadowing agreements." <p>This is how directory servers replicate information. </p> </td> <td>ITU Recommendation X.525 </td></tr> <tr> <td>Directory Operational Bindings Management Protocol (DOP) </td> <td>"Defines the exchange of administrative information between two DSAs to administer operational bindings between them." <p>This is how directories manage agreements, such as those relating to replication, between each other. </p> </td> <td>ITU Recommendation X.501 </td></tr> <tr> <td>Certificate Authority Subscription Protocol (CASP) </td> <td> </td> <td>ITU Recommendation X.509 </td></tr> <tr> <td>Authorization Validation Management Protocol (AVMP) </td> <td> </td> <td>ITU Recommendation X.509 </td></tr> <tr> <td>Trust Broker Protocol (TBP) </td> <td> </td> <td>ITU Recommendation X.510 </td></tr></tbody></table> <p>* These protocols are typically defined piecemeal throughout multiple specifications and <a href="/wiki/ASN.1" title="ASN.1">ASN.1</a> modules. The "Defining Specification" column above indicates (subjectively) which specification contributes most specifically to a protocol. </p><p>Because these protocols used the <a href="/wiki/Open_Systems_Interconnection" class="mw-redirect" title="Open Systems Interconnection">OSI</a> networking stack, a number of alternatives to DAP were developed to allow Internet clients to access the X.500 Directory using the <a href="/wiki/Internet_protocol_suite" title="Internet protocol suite">TCP/IP</a> networking stack. The most well-known alternative to DAP is Lightweight Directory Access Protocol (<a href="/wiki/Lightweight_Directory_Access_Protocol" title="Lightweight Directory Access Protocol">LDAP</a>). While DAP and the other X.500 protocols can now use the TCP/IP networking stack, LDAP remains a popular directory access protocol. </p> <div class="mw-heading mw-heading2"><h2 id="Transport_Protocols">Transport Protocols</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=X.500&action=edit&section=2" title="Edit section: Transport Protocols"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The X.500 protocols traditionally use the <a href="/wiki/Open_Systems_Interconnection" class="mw-redirect" title="Open Systems Interconnection">OSI</a> networking stack. However, the Lightweight Directory Access Protocol (<a href="/wiki/Lightweight_Directory_Access_Protocol" title="Lightweight Directory Access Protocol">LDAP</a>) uses TCP/IP for transport. In later versions of the ITU Recommendation X.519, the Internet Directly-Mapped (IDM) protocols were introduced to allow X.500 protocol data units (PDUs) to be transported over the TCP/IP stack. This transport involves ISO Transport over TCP as well as a simple record-based binary protocol to frame protocol datagrams. </p> <div class="mw-heading mw-heading2"><h2 id="X.500_data_models">X.500 data models</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=X.500&action=edit&section=3" title="Edit section: X.500 data models"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The primary concept of X.500 is that there is a single <a href="/wiki/Directory_Information_Tree" class="mw-redirect" title="Directory Information Tree">Directory Information Tree</a> (DIT), a hierarchical organization of entries which are distributed across one or more servers, called <a href="/wiki/Directory_System_Agent" title="Directory System Agent">Directory System Agents</a> (DSA). An entry consists of a set of attributes, each attribute with one or more values. Each entry has a unique <a href="/wiki/Distinguished_Name" class="mw-redirect" title="Distinguished Name">Distinguished Name</a>, formed by combining its <a href="/wiki/Relative_Distinguished_Name" class="mw-redirect" title="Relative Distinguished Name">Relative Distinguished Name</a> (RDN), one or more attributes of the entry itself, and the RDNs of each of the superior entries up to the root of the DIT. As LDAP implements a very similar data model to that of X.500, there is further description of the data model in the article on <a href="/wiki/Lightweight_Directory_Access_Protocol" title="Lightweight Directory Access Protocol">LDAP</a>. </p><p><a href="/w/index.php?title=X.520&action=edit&redlink=1" class="new" title="X.520 (page does not exist)">X.520</a> and <a href="/w/index.php?title=X.521&action=edit&redlink=1" class="new" title="X.521 (page does not exist)">X.521</a> together provide a definition of a set of attributes and object classes to be used for representing people and organizations as entries in the DIT. They are one of the most widely deployed <a href="/wiki/White_pages_schema" title="White pages schema">white pages schema</a>. </p><p><a href="/wiki/X.509" title="X.509">X.509</a>, the portion of the standard providing for an authentication framework, is now also widely used outside of the X.500 directory protocols. It specifies a standard format for public-key certificates. </p> <div class="mw-heading mw-heading2"><h2 id="The_relationship_of_the_X.500_Directory_and_X.509v3_digital_certificates">The relationship of the X.500 Directory and X.509v3 digital certificates</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=X.500&action=edit&section=4" title="Edit section: The relationship of the X.500 Directory and X.509v3 digital certificates"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The current use of X.509v3 certificates outside the Directory structure loaded directly into <a href="/wiki/Web_browser" title="Web browser">web browsers</a> was necessary for e-commerce to develop by allowing for secure web based (SSL/TLS) communications which did not require the X.500 directory as a source of digital certificates as originally conceived in X.500 (1988). One should contrast the role of X.500 and X.509 to understand their relationship in that X.509 was designed to be the secure access method for updating X.500 before the WWW, but when web browsers became popular there needed to be a simple method of encrypting connections on the transport layer to web sites. Hence the trusted root certificates for supported certificate authorities were pre loaded into certificate storage areas on the personal computer or device. </p><p>Added security is envisaged by the scheduled 2011-2014 implementation of the US <a href="/wiki/National_Strategy_for_Trusted_Identities_in_Cyberspace" title="National Strategy for Trusted Identities in Cyberspace">National Strategy for Trusted Identities in Cyberspace</a>, a two- to three-year project protecting digital identities in cyberspace.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p><p>The WWW e-commerce implementation of X.509v3 bypassed but did not replace the original ISO standard authentication mechanism of binding distinguished names in the X.500 Directory. </p><p>These packages of certificates can be added or removed by the end user in their software, but are reviewed by Microsoft and Mozilla in terms of their continued trustworthiness. Should a problem arise, such as what occurred with <a href="/wiki/DigiNotar" title="DigiNotar">DigiNotar</a>, browser security experts can issue an update to mark a certificate authority as untrusted, but this is a serious removal effectively of that CA from "internet trust". X.500 offers a way to view which organization claims a specific root certificate, outside of that provided bundle. This can function as a "4 corner model of trust" adding another check to determine if a root certificate has been compromised. Rules governing the Federal Bridge policy for revoking compromised certificates are available at <a rel="nofollow" class="external text" href="https://www.idmanagement.gov">www.idmanagement.gov</a>. </p><p>The contrast of this browser bundled approach is that in X.500 or LDAP the attribute "caCertificate" can be "bound" to a directory entry and checked in addition to the default pre-loaded bundle of certificates of which end users typically have never noticed unless an SSL warning message has appeared. </p><p>For example, a web site using SSL, typically the DNS site name "www.foobar.com" is verified in a browser by the software using libraries that would check to see if the certificate was signed by one of the trusted root certificates given to the user. </p><p>Therefore, creating trust for users that they had reached the correct web site via HTTPS. </p><p>However, stronger checks are also possible, to indicate that more than the domain name was verified. To contrast this with X.500, the certificate is one attribute of many for an entry, in which the entry could contain anything allowable by the specific Directory schema. Thus X.500 does store the digital certificate, but it is one of many attributes that could potentially verify the organization, such as physical address, a contact telephone number and an email contact. </p><p>CA Certs or certificate authority certs are loaded into the browser automatically (in the case of Microsoft's update mechanism), or in new version updates of browsers, and the user is given further choices to import, delete, or develop an individual trust relationship with the loaded Certificate Authorities and determine how the browser will behave if OCSP revocation servers are unreachable. </p><p>This is in contrast with the Directory model which associates the attribute <a rel="nofollow" class="external text" href="http://tools.ietf.org/html/rfc4523">caCertificate</a> with a listed certificate authority. </p><p>Thus the browser can verify the SSL cert of the website by means of the loaded group of accepted certificates or the root certificates can be looked up in an X.500 or LDAP Directory (or via HTTP/S) and imported into the list of trusted certificate authorities. </p><p>The "bound" distinguished name is located in the subject fields of the certificate which matches the Directory entry. X.509v3 can contain other extensions depending on the community of interest other than international domain names. For broad Internet use, RFC-5280 PKIX describes a profile for fields that may be useful for applications such as encrypted email. </p><p>An end user who relies on the authenticity of a certificate being presented to a browser or email has no simple way to compare a forged certificate presented (perhaps which triggers a browser warning) with a valid certificate, without also being given the opportunity to validate the DN or Distinguished Name which was designed to be looked up in an X.500 DIT. </p><p>The certificate itself is public and considered to be unforgeable and can therefore be distributed in any manner, but an associated binding to an identity occurs in the Directory. Binding is what links the certificate to the identity who claims to be using that certificate. For example, the X.500 software that runs the Federal Bridge has cross certificates that enable trust between certificate authorities. </p><p>Simple homographic matching of domain names has resulted in phishing attacks where a domain can appear to be legitimate, but is not. </p><p>If a X.509v3 certificate is bound to a valid organization's distinguished name within the Directory, then a simple check can be made in regards to the authenticity of the certificate by a comparison with what is presented to the browser with what is present in the Directory. </p><p>Some options do exist to check notaries to see if a certificate has only recently been seen, and therefore more likely to have been compromised.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> If the cert is likely to be trusted and is failing because the domain name is a slight mismatch, it will then initially fail in the browser, but then be subjected to the notary trust, which can then bypass the browser warning. </p><p>A valid organizational entry, such as o=FoobarWidgets, will also have an associated alphanumeric OID, and it has been "identity proofed" by ANSI, providing another layer of assurance regarding binding the certificate to the identity. </p><p>Recent events (2011) have indicated a threat from unknown actors in nation states who have forged certificates. This was done in order to create a <a href="/wiki/Man-in-the-middle_attack" title="Man-in-the-middle attack">MITM</a> attack against political activists in Syria accessing Facebook over the web. This would have normally triggered a browser warning, but would not if the MITM certificate was issued by a valid certificate authority already trusted by a browser or other software. Similar attacks were used by Stuxnet which allowed software to impersonate trusted code. The point of certificate transparency is to allow an end user to determine, using a simple procedure if a certificate is in fact valid. Checking against the default bundle of certificates may not be enough to do this, and therefore an additional check is desired. Other suggestions for certificate transparency have also been advanced.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p><p>A different attack was used against Comodo, a certificate authority, that resulted in forged certificates that were directed at high-profile communications websites. This necessitated an emergency patch to major browsers. These certificates were actually issued from a trusted Certificate Authority, and therefore a user would have had no warning if they had gone to a faked website, in contrast with the Syria incident, where the certificate was crudely forged, including substituting Alto Palo, for Palo Alto. and incorrect serial numbers. </p><p>Some projects designed to exchange PHI, protected Health Information (which is considered to be highly <a href="/wiki/Health_Insurance_Portability_and_Accountability_Act" title="Health Insurance Portability and Accountability Act">HIPAA</a> sensitive) may obtain X.509v3 certs via a CERT DNS resource record, or via LDAP to a X.500[2008] Directory. The issue of an authoritative bind then is detailed in RFCs related to the accuracy of the DNS information secured by signing from the root using DNSSEC. </p><p>The concept of root name servers has been a source of major contention in the Internet community, but for DNS is largely resolved. The name space associated with X.500 has traditionally been thought to start with a national naming authority, which mirrors the ISO/ITU approach to global systems with national representation. Thus different countries will create their own unique X.500 services. The U.S. X.500 was privatized in 1998, when the U.S. Government no longer offered X.500 or DNS registration outside of known government agencies. </p><p>The X.500 pilot project has been in development in the commercial space, and the technology continues to be present in major installations of millions of users within corporate data centers, and within the U.S. Government for credentialing. </p> <div class="mw-heading mw-heading2"><h2 id="List_of_X.500_series_standards">List of X.500 series standards</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=X.500&action=edit&section=5" title="Edit section: List of X.500 series standards"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <table class="wikitable"> <tbody><tr> <th>ITU-T number </th> <th><a href="/wiki/ISO/IEC" class="mw-redirect" title="ISO/IEC">ISO/IEC</a> number </th> <th>Title of Standard </th></tr> <tr> <td> </td> <td><a href="/w/index.php?title=ISO/IEC_9594-1&action=edit&redlink=1" class="new" title="ISO/IEC 9594-1 (page does not exist)">ISO/IEC 9594-1</a> </td> <td>The Directory: Overview of concepts, models and services </td></tr> <tr> <td> </td> <td><a href="/w/index.php?title=ISO/IEC_9594-2&action=edit&redlink=1" class="new" title="ISO/IEC 9594-2 (page does not exist)">ISO/IEC 9594-2</a> </td> <td>The Directory: Models </td></tr> <tr> <td> </td> <td><a href="/w/index.php?title=ISO/IEC_9594-8&action=edit&redlink=1" class="new" title="ISO/IEC 9594-8 (page does not exist)">ISO/IEC 9594-8</a> </td> <td>The Directory: <a href="/wiki/Public-key" class="mw-redirect" title="Public-key">Public-key</a> and attribute certificate frameworks </td></tr> <tr> <td><a href="/w/index.php?title=ISO/IEC_9594-3&action=edit&redlink=1" class="new" title="ISO/IEC 9594-3 (page does not exist)">ISO/IEC 9594-3</a> </td> <td>The Directory: Abstract service definition </td></tr> <tr> <td>[] </td> <td><a href="/w/index.php?title=ISO/IEC_9594-4&action=edit&redlink=1" class="new" title="ISO/IEC 9594-4 (page does not exist)">ISO/IEC 9594-4</a> </td> <td>The Directory: Procedures for distributed operation </td></tr> <tr> <td>[] </td> <td><a href="/w/index.php?title=ISO/IEC_9594-5&action=edit&redlink=1" class="new" title="ISO/IEC 9594-5 (page does not exist)">ISO/IEC 9594-5</a> </td> <td>The Directory: Protocol specifications </td></tr> <tr> <td> </td> <td><a href="/w/index.php?title=ISO/IEC_9594-6&action=edit&redlink=1" class="new" title="ISO/IEC 9594-6 (page does not exist)">ISO/IEC 9594-6</a> </td> <td>The Directory: Selected attribute types </td></tr> <tr> <td>[[]] </td> <td><a href="/w/index.php?title=ISO/IEC_9594-7&action=edit&redlink=1" class="new" title="ISO/IEC 9594-7 (page does not exist)">ISO/IEC 9594-7</a> </td> <td>The Directory: Selected object classes </td></tr> <tr> <td>[[]] </td> <td><a href="/w/index.php?title=ISO/IEC_9594-9&action=edit&redlink=1" class="new" title="ISO/IEC 9594-9 (page does not exist)">ISO/IEC 9594-9</a> </td> <td>The Directory: Replication </td></tr> <tr> <td>[[]] </td> <td><a href="/w/index.php?title=ISO/IEC_9594-10&action=edit&redlink=1" class="new" title="ISO/IEC 9594-10 (page does not exist)">ISO/IEC 9594-10</a> </td> <td>The Directory: Use of systems management for administration of the Directory </td></tr></tbody></table> <div class="mw-heading mw-heading2"><h2 id="Criticism">Criticism</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=X.500&action=edit&section=6" title="Edit section: Criticism"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The authors of RFC 2693 (concerning <a href="/wiki/SPKI" class="mw-redirect" title="SPKI">SPKI</a>) note that "The original X.500 plan is unlikely ever to come to fruition. Collections of directory entries... are considered valuable or even confidential by those owning the lists and are not likely to be released to the world in the form of an X.500 directory sub-tree." and that "The X.500 idea of a distinguished name (a single, globally unique name that everyone could use when referring to an entity) is also not likely to occur." </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=X.500&action=edit&section=7" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/ISO/IEC_JTC_1/SC_6" title="ISO/IEC JTC 1/SC 6">ISO/IEC JTC 1/SC 6</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=X.500&action=edit&section=8" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://www.collectionscanada.gc.ca/iso/ill/document/ill_directory/X_500andLDAP.pdf">X.500 and LDAP</a>collectionscanada.gc.ca <a rel="nofollow" class="external text" href="https://web.archive.org/web/20210401105523/https://www.collectionscanada.gc.ca/iso/ill/document/ill_directory/X_500andLDAP.pdf">Archived</a> 2021-04-01 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.nist.gov/nstic">"National Strategy for Trusted Identities in Cyberspace"</a><span class="reference-accessdate">. Retrieved <span class="nowrap">10 September</span> 2023</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=National+Strategy+for+Trusted+Identities+in+Cyberspace&rft_id=https%3A%2F%2Fwww.nist.gov%2Fnstic&rfr_id=info%3Asid%2Fen.wikipedia.org%3AX.500" class="Z3988"></span></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFWendlandtAndersenPerrig2008" class="citation journal cs1">Wendlandt, Dan; Andersen, David G.; Perrig, Adrian (June 2008). <a rel="nofollow" class="external text" href="https://www.usenix.org/legacy/events/usenix08/tech/full_papers/wendlandt/wendlandt.pdf">"Perspectives: Improving SSH-style Host Authentication with Multi-Path Probing"</a> <span class="cs1-format">(PDF)</span>. <i>Proceedings of the 2008 USENIX Annual Technical Conference</i>: <span class="nowrap">321–</span>334.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Proceedings+of+the+2008+USENIX+Annual+Technical+Conference&rft.atitle=Perspectives%3A+Improving+SSH-style+Host+Authentication+with+Multi-Path+Probing&rft.pages=%3Cspan+class%3D%22nowrap%22%3E321-%3C%2Fspan%3E334&rft.date=2008-06&rft.aulast=Wendlandt&rft.aufirst=Dan&rft.au=Andersen%2C+David+G.&rft.au=Perrig%2C+Adrian&rft_id=https%3A%2F%2Fwww.usenix.org%2Flegacy%2Fevents%2Fusenix08%2Ftech%2Ffull_papers%2Fwendlandt%2Fwendlandt.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AX.500" class="Z3988"></span></span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.certificate-transparency.org/">"Certificate Transparency"</a>. <i>www.certificate-transparency.org</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.certificate-transparency.org&rft.atitle=Certificate+Transparency&rft_id=http%3A%2F%2Fwww.certificate-transparency.org%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AX.500" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=X.500&action=edit&section=9" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHardcastle-Kille1993" class="citation journal cs1">Hardcastle-Kille, S. (1993). <a rel="nofollow" class="external text" href="https://tools.ietf.org/html/rfc1485">"RFC1485: A String Representation of Distinguished Names"</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.17487%2FRFC1485">10.17487/RFC1485</a></span><span class="reference-accessdate">. Retrieved <span class="nowrap">2021-02-10</span></span>. <q>Many OSI Applications make use of Distinguished Names (DN) as defined in the OSI Directory, commonly known as X.500 [CCI88]. This specification assumes familiarity with X.500, and the concept of Distinguished Name.</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=RFC1485%3A+A+String+Representation+of+Distinguished+Names&rft.date=1993&rft_id=info%3Adoi%2F10.17487%2FRFC1485&rft.aulast=Hardcastle-Kille&rft.aufirst=S.&rft_id=https%3A%2F%2Ftools.ietf.org%2Fhtml%2Frfc1485&rfr_id=info%3Asid%2Fen.wikipedia.org%3AX.500" class="Z3988"></span> <span class="cs1-visible-error citation-comment"><code class="cs1-code">{{<a href="/wiki/Template:Cite_journal" title="Template:Cite journal">cite journal</a>}}</code>: </span><span class="cs1-visible-error citation-comment">Cite journal requires <code class="cs1-code">|journal=</code> (<a href="/wiki/Help:CS1_errors#missing_periodical" title="Help:CS1 errors">help</a>)</span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFChadwick1994" class="citation web cs1">Chadwick, D W (1994). <a rel="nofollow" class="external text" href="http://sec.cs.kent.ac.uk/x500book/">"Understanding X.500 - The Directory"</a><span class="reference-accessdate">. Retrieved <span class="nowrap">2017-12-06</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Understanding+X.500+-+The+Directory&rft.date=1994&rft.aulast=Chadwick&rft.aufirst=D+W&rft_id=http%3A%2F%2Fsec.cs.kent.ac.uk%2Fx500book%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AX.500" class="Z3988"></span></li> <li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20190104231951/http://www.x500standard.com/">X500Standard.com – The X.500 community site that is both a guide to the X.500 Standard and a repository for existing and new work being carried out on the standard.</a> at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a> (archived January 4, 2019)</li></ul> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output 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.navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:ISO_standards" title="Template:ISO standards"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:ISO_standards" title="Template talk:ISO standards"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:ISO_standards" title="Special:EditPage/Template:ISO standards"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="ISO_standards_by_standard_number451" style="font-size:114%;margin:0 4em"><a href="/wiki/International_Organization_for_Standardization" title="International Organization for Standardization">ISO</a> standards <span class="nobold">by standard number</span></div></th></tr><tr><td class="navbox-abovebelow" colspan="2"><div>List of <a href="/wiki/List_of_ISO_standards" title="List of ISO standards">ISO standards</a> – <a href="/wiki/List_of_ISO_romanizations" title="List of ISO romanizations">ISO romanizations</a> – <a href="/wiki/List_of_IEC_standards" title="List of IEC standards">IEC standards</a></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">1–9999</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/ISO_1" title="ISO 1">1</a></li> <li><a href="/wiki/ISO_2" title="ISO 2">2</a></li> <li><a href="/wiki/Renard_series" title="Renard series">3</a></li> <li><a href="/wiki/ISO_4" title="ISO 4">4</a></li> <li><a href="/wiki/Film_speed" title="Film speed">6</a></li> <li><a href="/wiki/British_Standard_Pipe" title="British Standard Pipe">7</a></li> <li><a href="/wiki/ISO_9" title="ISO 9">9</a></li> <li><a href="/wiki/A440_(pitch_standard)" title="A440 (pitch standard)">16</a></li> <li><a href="/wiki/Renard_series" title="Renard series">17</a></li> <li><a href="/wiki/ISO_31" title="ISO 31">31</a> <ul><li><a href="/wiki/ISO_31-0" title="ISO 31-0">-0</a></li> <li><a href="/wiki/ISO_31-1" title="ISO 31-1">-1</a></li> <li><a href="/wiki/ISO_31-3" title="ISO 31-3">-3</a></li> <li><a href="/wiki/ISO_31-4" title="ISO 31-4">-4</a></li> <li><a href="/wiki/ISO_31-5" title="ISO 31-5">-5</a></li> <li><a href="/wiki/ISO_31-6" title="ISO 31-6">-6</a></li> <li><a href="/wiki/ISO_31-7" title="ISO 31-7">-7</a></li> <li><a href="/wiki/ISO_31-8" title="ISO 31-8">-8</a></li> <li><a href="/wiki/ISO_31-9" class="mw-redirect" title="ISO 31-9">-9</a></li> <li><a href="/wiki/ISO_31-10" title="ISO 31-10">-10</a></li> <li><a href="/wiki/ISO_31-11" title="ISO 31-11">-11</a></li> <li><a href="/wiki/ISO_31-12" class="mw-redirect" title="ISO 31-12">-12</a></li> <li><a href="/wiki/ISO_31-13" class="mw-redirect" title="ISO 31-13">-13</a></li></ul></li> <li><a href="/wiki/ISO_metric_screw_thread" title="ISO metric screw thread">68-1</a></li> <li><a href="/wiki/ISO_128" title="ISO 128">128</a></li> <li><a href="/wiki/ISO_216" title="ISO 216">216</a></li> <li><a href="/wiki/ISO_217" title="ISO 217">217</a></li> <li><a href="/wiki/Equal-loudness_contour" title="Equal-loudness contour">226</a></li> <li><a href="/wiki/British_Standard_Pipe" title="British Standard Pipe">228</a></li> <li><a href="/wiki/ISO_233" title="ISO 233">233</a></li> <li><a href="/wiki/ISO_259" title="ISO 259">259</a></li> <li><a href="/wiki/ISO_metric_screw_thread" title="ISO metric screw thread">261</a></li> <li><a href="/wiki/ISO_metric_screw_thread" title="ISO metric screw thread">262</a></li> <li><a href="/wiki/Kappa_number" title="Kappa number">302</a></li> <li><a href="/wiki/Vicat_softening_point" title="Vicat softening point">306</a></li> <li><a href="/wiki/Hazard_symbol#Ionizing_radiation_symbol" title="Hazard symbol">361</a></li> <li><a href="/wiki/Power_take-off" title="Power take-off">500</a></li> <li><a href="/wiki/Hot_shoe" title="Hot shoe">518</a></li> <li><a href="/wiki/Prontor-Compur" title="Prontor-Compur">519</a></li> <li><a href="/wiki/ISO_639" title="ISO 639">639</a> <ul><li><a href="/wiki/ISO_639-1" title="ISO 639-1">-1</a></li> <li><a href="/wiki/ISO_639-2" title="ISO 639-2">-2</a></li> <li><a href="/wiki/ISO_639-3" title="ISO 639-3">-3</a></li> <li><a href="/wiki/ISO_639-5" title="ISO 639-5">-5</a></li> <li><a href="/wiki/ISO_639-6" title="ISO 639-6">-6</a></li></ul></li> <li><a href="/wiki/ISO/IEC_646" title="ISO/IEC 646">646</a></li> <li><a href="/wiki/ISO_657" title="ISO 657">657</a></li> <li><a href="/wiki/ISO_668" title="ISO 668">668</a></li> <li><a href="/wiki/ISO_690" title="ISO 690">690</a></li> <li><a href="/wiki/ISO_704" title="ISO 704">704</a></li> <li><a href="/wiki/ISO_732" title="ISO 732">732</a></li> <li><a href="/wiki/Antimagnetic_watch" title="Antimagnetic watch">764</a></li> <li><a href="/wiki/Hole_punch" title="Hole punch">838</a></li> <li><a href="/wiki/ISO_843" title="ISO 843">843</a></li> <li><a href="/wiki/ISO_860" title="ISO 860">860</a></li> <li><a href="/wiki/ISO_898" title="ISO 898">898</a></li> <li><a href="/wiki/ISO_965" title="ISO 965">965</a></li> <li><a href="/wiki/ISO_999" title="ISO 999">999</a></li> <li><a href="/wiki/ISO_1000" title="ISO 1000">1000</a></li> <li><a href="/wiki/Magnetic_ink_character_recognition" title="Magnetic ink character recognition">1004</a></li> <li><a href="/wiki/135_film" title="135 film">1007</a></li> <li><a href="/wiki/OCR-A" title="OCR-A">1073-1</a></li> <li><a href="/wiki/OCR-B" title="OCR-B">1073-2</a></li> <li><a href="/wiki/Longitudinal_redundancy_check" title="Longitudinal redundancy check">1155</a></li> <li><a href="/wiki/Shock-resistant_watch#ISO_1413_shock-resistant_standard" title="Shock-resistant watch">1413</a></li> <li><a href="/wiki/ALGOL_60" title="ALGOL 60">1538</a></li> <li><a href="/wiki/ISO_1629" title="ISO 1629">1629</a></li> <li><a href="/wiki/ISO_1745" title="ISO 1745">1745</a></li> <li><a href="/wiki/COBOL" title="COBOL">1989</a></li> <li><a href="/wiki/ISO_2014" title="ISO 2014">2014</a></li> <li><a href="/wiki/ISO_2015" title="ISO 2015">2015</a></li> <li><a href="/wiki/ISO/IEC_2022" title="ISO/IEC 2022">2022</a></li> <li><a href="/wiki/ISO_2033" title="ISO 2033">2033</a></li> <li><a href="/wiki/ISO_2047" title="ISO 2047">2047</a></li> <li><a href="/wiki/ISBN" title="ISBN">2108</a></li> <li><a href="/wiki/ISO_2145" title="ISO 2145">2145</a></li> <li><a href="/wiki/ISO_2146" title="ISO 2146">2146</a></li> <li><a href="/wiki/Film_speed" title="Film speed">2240</a></li> <li><a href="/wiki/Water_Resistant_mark" title="Water Resistant mark">2281</a></li> <li><a href="/wiki/International_Standard_Atmosphere" title="International Standard Atmosphere">2533</a></li> <li><a href="/wiki/ISO_2709" title="ISO 2709">2709</a></li> <li><a href="/wiki/ISO_2711" title="ISO 2711">2711</a></li> <li><a href="/wiki/Film_speed" title="Film speed">2720</a></li> <li><a href="/wiki/ISO_2788" title="ISO 2788">2788</a></li> <li><a href="/wiki/ISO_2848" title="ISO 2848">2848</a></li> <li><a href="/wiki/ISO_2852" title="ISO 2852">2852</a></li> <li><a href="/wiki/ISO_2921" title="ISO 2921">2921</a></li> <li><a href="/wiki/126_film" title="126 film">3029</a></li> <li><a href="/wiki/ISO_3103" title="ISO 3103">3103</a></li> <li><a href="/wiki/ISO_3166" title="ISO 3166">3166</a> <ul><li><a href="/wiki/ISO_3166-1" title="ISO 3166-1">-1</a></li> <li><a href="/wiki/ISO_3166-2" title="ISO 3166-2">-2</a></li> <li><a href="/wiki/ISO_3166-3" title="ISO 3166-3">-3</a></li></ul></li> <li><a href="/wiki/ISSN" title="ISSN">3297</a></li> <li><a href="/wiki/ISO_3307" title="ISO 3307">3307</a></li> <li><a href="/wiki/O-ring" title="O-ring">3601</a></li> <li><a href="/wiki/Kunrei-shiki_romanization" title="Kunrei-shiki romanization">3602</a></li> <li><a href="/wiki/ISO_3864" title="ISO 3864">3864</a></li> <li><a href="/wiki/International_Standard_Recording_Code" title="International Standard Recording Code">3901</a></li> <li><a href="/wiki/FDI_World_Dental_Federation_notation" title="FDI World Dental Federation notation">3950</a></li> <li><a href="/wiki/ISO_3977" title="ISO 3977">3977</a></li> <li><a href="/wiki/ISO_4031" title="ISO 4031">4031</a></li> <li><a href="/wiki/ISO_4157" class="mw-redirect" title="ISO 4157">4157</a></li> <li><a href="/wiki/ISO_4165" title="ISO 4165">4165</a></li> <li><a href="/wiki/ISO_4217" title="ISO 4217">4217</a></li> <li><a href="/wiki/ISO/IEC_4909" title="ISO/IEC 4909">4909</a></li> <li><a href="/wiki/ISO/IEC_5218" title="ISO/IEC 5218">5218</a></li> <li><a href="/wiki/ISO_5426" title="ISO 5426">5426</a></li> <li><a href="/wiki/ISO_5427" title="ISO 5427">5427</a></li> <li><a href="/wiki/ISO_5428" title="ISO 5428">5428</a></li> <li><a href="/wiki/Accuracy_and_precision" title="Accuracy and precision">5725</a></li> <li><a href="/wiki/ISO_5775" title="ISO 5775">5775</a></li> <li><a href="/wiki/ISO_5776" title="ISO 5776">5776</a></li> <li><a href="/wiki/Film_speed" title="Film speed">5800</a></li> <li><a href="/wiki/Flowchart" title="Flowchart">5807</a></li> <li><a href="/wiki/ISO_5964" title="ISO 5964">5964</a></li> <li><a href="/wiki/International_Securities_Identification_Number" title="International Securities Identification Number">6166</a></li> <li><a href="/wiki/ISO_6344" title="ISO 6344">6344</a></li> <li><a href="/wiki/ISO_6346" title="ISO 6346">6346</a></li> <li><a href="/wiki/Minimal_BASIC" title="Minimal BASIC">6373</a></li> <li><a href="/wiki/ISO_6385" title="ISO 6385">6385</a></li> <li><a href="/wiki/Water_Resistant_mark" title="Water Resistant mark">6425</a></li> <li><a href="/wiki/ANSI_escape_code" title="ANSI escape code">6429</a></li> <li><a href="/wiki/ISO_6438" title="ISO 6438">6438</a></li> <li><a href="/wiki/ISO/IEC_6523" title="ISO/IEC 6523">6523</a></li> <li><a href="/wiki/ISO_6709" title="ISO 6709">6709</a></li> <li><a href="/wiki/ISO_6943" title="ISO 6943">6943</a></li> <li><a href="/wiki/ISO_7001" title="ISO 7001">7001</a></li> <li><a href="/wiki/ISO_7002" title="ISO 7002">7002</a></li> <li><a href="/wiki/ISO_7010" title="ISO 7010">7010</a></li> <li><a href="/wiki/ISO_7027" title="ISO 7027">7027</a></li> <li><a href="/wiki/ISO/IEC_7064" title="ISO/IEC 7064">7064</a></li> <li><a href="/wiki/Pinyin" title="Pinyin">7098</a></li> <li><a href="/wiki/Pascal_(programming_language)" title="Pascal (programming language)">7185</a></li> <li><a href="/wiki/ISO_7200" title="ISO 7200">7200</a></li> <li><a href="/wiki/OSI_model" title="OSI model">7498</a> <ul><li><a href="/wiki/OSI_model" title="OSI model">-1</a></li></ul></li> <li><a href="/wiki/ISO_7637" title="ISO 7637">7637</a></li> <li><a href="/wiki/ISO_7736" title="ISO 7736">7736</a></li> <li><a href="/wiki/ISO/IEC_7810" title="ISO/IEC 7810">7810</a></li> <li><a href="/wiki/ISO/IEC_7811" title="ISO/IEC 7811">7811</a></li> <li><a href="/wiki/ISO/IEC_7812" title="ISO/IEC 7812">7812</a></li> <li><a href="/wiki/ISO/IEC_7813" title="ISO/IEC 7813">7813</a></li> <li><a href="/wiki/ISO/IEC_7816" title="ISO/IEC 7816">7816</a></li> <li><a href="/wiki/Graphical_Kernel_System" title="Graphical Kernel System">7942</a></li> <li><a href="/wiki/ISO_8000" title="ISO 8000">8000</a></li> <li><a href="/wiki/On-board_diagnostics" title="On-board diagnostics">8093</a></li> <li><a href="/wiki/ISO_8178" title="ISO 8178">8178</a></li> <li><a href="/wiki/Fuel_oil" title="Fuel oil">8217</a></li> <li><a href="/wiki/ISO_8373" class="mw-redirect" title="ISO 8373">8373</a></li> <li><a href="/wiki/ISO_8501-1" title="ISO 8501-1">8501-1</a></li> <li><a href="/wiki/FTAM" title="FTAM">8571</a></li> <li><a href="/wiki/ISO_8583" title="ISO 8583">8583</a></li> <li><a href="/wiki/ISO_8601" title="ISO 8601">8601</a></li> <li><a href="/wiki/Open_Document_Architecture" title="Open Document Architecture">8613</a></li> <li><a href="/wiki/Computer_Graphics_Metafile" title="Computer Graphics Metafile">8632</a></li> <li><a href="/wiki/Graphical_Kernel_System" title="Graphical Kernel System">8651</a></li> <li><a href="/wiki/ISO/IEC_8652" title="ISO/IEC 8652">8652</a></li> <li><a href="/wiki/ISO_8691" title="ISO 8691">8691</a></li> <li><a href="/wiki/Graphical_Kernel_System" title="Graphical Kernel System">8805/8806</a></li> <li><a href="/wiki/Language_of_Temporal_Ordering_Specification" title="Language of Temporal Ordering Specification">8807</a></li> <li><a href="/wiki/Automotive_fuse" title="Automotive fuse">8820-5</a></li> <li><a href="/wiki/ISO/IEC_8859" title="ISO/IEC 8859">8859</a> <ul><li><a href="/wiki/ISO/IEC_8859-1" title="ISO/IEC 8859-1">-1</a></li> <li><a href="/wiki/ISO/IEC_8859-2" title="ISO/IEC 8859-2">-2</a></li> <li><a href="/wiki/ISO/IEC_8859-3" title="ISO/IEC 8859-3">-3</a></li> <li><a href="/wiki/ISO/IEC_8859-4" title="ISO/IEC 8859-4">-4</a></li> <li><a href="/wiki/ISO/IEC_8859-5" title="ISO/IEC 8859-5">-5</a></li> <li><a href="/wiki/ISO/IEC_8859-6" title="ISO/IEC 8859-6">-6</a></li> <li><a href="/wiki/ISO/IEC_8859-7" title="ISO/IEC 8859-7">-7</a></li> <li><a href="/wiki/ISO/IEC_8859-8" title="ISO/IEC 8859-8">-8</a></li> <li><a href="/wiki/ISO-8859-8-I" title="ISO-8859-8-I">-8-I</a></li> <li><a href="/wiki/ISO/IEC_8859-9" title="ISO/IEC 8859-9">-9</a></li> <li><a href="/wiki/ISO/IEC_8859-10" title="ISO/IEC 8859-10">-10</a></li> <li><a href="/wiki/ISO/IEC_8859-11" title="ISO/IEC 8859-11">-11</a></li> <li><a href="/wiki/ISO/IEC_8859-12" class="mw-redirect" title="ISO/IEC 8859-12">-12</a></li> <li><a href="/wiki/ISO/IEC_8859-13" title="ISO/IEC 8859-13">-13</a></li> <li><a href="/wiki/ISO/IEC_8859-14" title="ISO/IEC 8859-14">-14</a></li> <li><a href="/wiki/ISO/IEC_8859-15" title="ISO/IEC 8859-15">-15</a></li> <li><a href="/wiki/ISO/IEC_8859-16" title="ISO/IEC 8859-16">-16</a></li></ul></li> <li><a href="/wiki/Standard_Generalized_Markup_Language" title="Standard Generalized Markup Language">8879</a></li> <li><a href="/wiki/ISO_9000_family" title="ISO 9000 family">9000/9001</a></li> <li><a href="/wiki/ASMO_449" title="ASMO 449">9036</a></li> <li><a href="/wiki/SQL" title="SQL">9075</a></li> <li><a href="/wiki/ISO/IEC_9126" title="ISO/IEC 9126">9126</a></li> <li><a href="/wiki/On-board_diagnostics" title="On-board diagnostics">9141</a></li> <li><a href="/wiki/Salt_spray_test" title="Salt spray test">9227</a></li> <li><a href="/wiki/ISO_9241" title="ISO 9241">9241</a></li> <li><a href="/wiki/File_Allocation_Table" title="File Allocation Table">9293</a></li> <li><a href="/wiki/Fiber_Distributed_Data_Interface" title="Fiber Distributed Data Interface">9314</a></li> <li><a href="/wiki/ISO_9362" title="ISO 9362">9362</a></li> <li><a href="/wiki/Shoe_size" title="Shoe size">9407</a></li> <li><a href="/wiki/CHILL" title="CHILL">9496</a></li> <li><a href="/wiki/Manufacturing_Message_Specification" title="Manufacturing Message Specification">9506</a></li> <li><a href="/wiki/ISO/IEC_9529" title="ISO/IEC 9529">9529</a></li> <li><a href="/wiki/ISO_9564" title="ISO 9564">9564</a></li> <li><a href="/wiki/PHIGS" title="PHIGS">9592/9593</a></li> <li><a class="mw-selflink selflink">9594</a></li> <li><a href="/wiki/ISO_9660" title="ISO 9660">9660</a></li> <li><a href="/wiki/ISO/IEC_9797-1" title="ISO/IEC 9797-1">9797-1</a></li> <li><a href="/wiki/ISO_9897" title="ISO 9897">9897</a></li> <li><a href="/wiki/ANSI_C" title="ANSI C">9899</a></li> <li><a href="/wiki/POSIX" title="POSIX">9945</a></li> <li><a href="/wiki/Romanization_of_Georgian" title="Romanization of Georgian">9984</a></li> <li><a href="/wiki/Romanization_of_Armenian" title="Romanization of Armenian">9985</a></li> <li><a href="/wiki/ISO/IEC_9995" title="ISO/IEC 9995">9995</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">10000–19999</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/ISO_10006" title="ISO 10006">10006</a></li> <li><a href="/wiki/ISO_10007" title="ISO 10007">10007</a></li> <li><a href="/wiki/ISO/IEC_10116" title="ISO/IEC 10116">10116</a></li> <li><a href="/wiki/Whirlpool_(hash_function)" title="Whirlpool (hash function)">10118-3</a></li> <li><a href="/wiki/ISO_10160" title="ISO 10160">10160</a></li> <li><a href="/wiki/ISO_10161" title="ISO 10161">10161</a></li> <li><a href="/wiki/Guidelines_for_the_Definition_of_Managed_Objects" title="Guidelines for the Definition of Managed Objects">10165</a></li> <li><a href="/wiki/Document_Style_Semantics_and_Specification_Language" title="Document Style Semantics and Specification Language">10179</a></li> <li><a href="/wiki/Pascal_(programming_language)#ISO/IEC_10206:1990_Extended_Pascal" title="Pascal (programming language)">10206</a></li> <li><a href="/wiki/ISO_10218" title="ISO 10218">10218</a></li> <li><a href="/wiki/Full_BASIC" title="Full BASIC">10279</a></li> <li><a href="/wiki/ISO_10303" title="ISO 10303">10303</a> <ul><li><a href="/wiki/EXPRESS_(data_modeling_language)" title="EXPRESS (data modeling language)">-11</a></li> <li><a href="/wiki/ISO_10303-21" title="ISO 10303-21">-21</a></li> <li><a href="/wiki/ISO_10303-22" title="ISO 10303-22">-22</a></li> <li><a href="/wiki/ISO_10303-28" title="ISO 10303-28">-28</a></li> <li><a href="/wiki/STEP-NC" title="STEP-NC">-238</a></li></ul></li> <li><a href="/wiki/Market_Identifier_Code" title="Market Identifier Code">10383</a></li> <li><a href="/wiki/ArmSCII" title="ArmSCII">10585</a></li> <li><a href="/wiki/IS-IS" title="IS-IS">10589</a></li> <li><a href="/wiki/ISO_10628" title="ISO 10628">10628</a></li> <li><a href="/wiki/Universal_Coded_Character_Set" title="Universal Coded Character Set">10646</a></li> <li><a href="/wiki/Torx" title="Torx">10664</a></li> <li><a href="/wiki/RM-ODP" title="RM-ODP">10746</a></li> <li><a href="/wiki/Multibus" title="Multibus">10861</a></li> <li><a href="/wiki/International_Standard_Music_Number" title="International Standard Music Number">10957</a></li> <li><a href="/wiki/ISO_10962" title="ISO 10962">10962</a></li> <li><a href="/wiki/ISO/IEC_10967" title="ISO/IEC 10967">10967</a></li> <li><a href="/wiki/ISO/IEEE_11073" title="ISO/IEEE 11073">11073</a></li> <li><a href="/wiki/ISO_11170" title="ISO 11170">11170</a></li> <li><a href="/wiki/MPEG-1" title="MPEG-1">11172</a></li> <li><a href="/wiki/ISO/IEC_11179" title="ISO/IEC 11179">11179</a></li> <li><a href="/wiki/ISO/IEC_11404" title="ISO/IEC 11404">11404</a></li> <li><a href="/wiki/JBIG" title="JBIG">11544</a></li> <li><a href="/wiki/ISO_11783" title="ISO 11783">11783</a></li> <li><a href="/wiki/ISO_11784_and_ISO_11785" title="ISO 11784 and ISO 11785">11784</a></li> <li><a href="/wiki/ISO_11784_and_ISO_11785" title="ISO 11784 and ISO 11785">11785</a></li> <li><a href="/wiki/ISO/IEC_11801" title="ISO/IEC 11801">11801</a></li> <li><a href="/wiki/Trusted_Platform_Module" title="Trusted Platform Module">11889</a></li> <li><a href="/wiki/CAN_bus#CAN_lower-layer_standards" title="CAN bus">11898</a></li> <li><a href="/wiki/ISO_11940" title="ISO 11940">11940</a> (<a href="/wiki/ISO_11940-2" title="ISO 11940-2">-2</a>)</li> <li><a href="/wiki/ISO/TR_11941" title="ISO/TR 11941">11941</a></li> <li><a href="/wiki/ISO/TR_11941" title="ISO/TR 11941">11941 (TR)</a></li> <li><a href="/wiki/ISO_11992" title="ISO 11992">11992</a></li> <li><a href="/wiki/ISO_12006" title="ISO 12006">12006</a></li> <li><a href="/wiki/DICOM" title="DICOM">12052</a></li> <li><a href="/wiki/ISO/IEC_TR_12182" title="ISO/IEC TR 12182">12182</a></li> <li><a href="/wiki/ISO/IEC_12207" title="ISO/IEC 12207">12207</a></li> <li><a href="/wiki/TIFF/EP" title="TIFF/EP">12234-2</a></li> <li><a href="/wiki/Linguistic_categories#ISO_12620_(ISO_TC37_Data_Category_Registry,_ISOcat)" title="Linguistic categories">12620</a></li> <li><a href="/wiki/Prolog" title="Prolog">13211</a> <ul><li><a href="/wiki/Prolog" title="Prolog">-1</a></li> <li><a href="/wiki/Prolog" title="Prolog">-2</a></li></ul></li> <li><a href="/wiki/Isofix" title="Isofix">13216</a></li> <li><a href="/wiki/Topic_map" title="Topic map">13250</a></li> <li><a href="/wiki/ISO_13399" title="ISO 13399">13399</a></li> <li><a href="/wiki/ISO_13406-2" title="ISO 13406-2">13406-2</a></li> <li><a href="/wiki/110_film" title="110 film">13450</a></li> <li><a href="/wiki/ISO_13485" title="ISO 13485">13485</a></li> <li><a href="/wiki/ISO_13490" title="ISO 13490">13490</a></li> <li><a href="/wiki/ISO_13567" title="ISO 13567">13567</a></li> <li><a href="/wiki/Z_notation" title="Z notation">13568</a></li> <li><a href="/wiki/ISO_13584" title="ISO 13584">13584</a></li> <li><a href="/wiki/International_Bank_Account_Number" title="International Bank Account Number">13616</a></li> <li><a href="/wiki/ISLISP" title="ISLISP">13816</a></li> <li><a href="/wiki/MPEG-2" title="MPEG-2">13818</a></li> <li><a href="/wiki/ISO_14000_family" title="ISO 14000 family">14000</a></li> <li><a href="/wiki/ISO_14031" title="ISO 14031">14031</a></li> <li><a href="/wiki/ISO_14224" title="ISO 14224">14224</a></li> <li><a href="/wiki/PDF/UA" title="PDF/UA">14289</a></li> <li><a href="/wiki/Horsepower" title="Horsepower">14396</a></li> <li><a href="/wiki/ISO/IEC_14443" title="ISO/IEC 14443">14443</a></li> <li><a href="/wiki/MPEG-4" title="MPEG-4">14496</a> <ul><li><a href="/wiki/MPEG-4_Part_2" title="MPEG-4 Part 2">-2</a></li> <li><a href="/wiki/MPEG-4_Part_3" title="MPEG-4 Part 3">-3</a></li> <li><a href="/wiki/Delivery_Multimedia_Integration_Framework" title="Delivery Multimedia Integration Framework">-6</a></li> <li><a href="/wiki/Advanced_Video_Coding" title="Advanced Video Coding">-10</a></li> <li><a href="/wiki/MPEG-4_Part_11" title="MPEG-4 Part 11">-11</a></li> <li><a href="/wiki/ISO_base_media_file_format" title="ISO base media file format">-12</a></li> <li><a href="/wiki/MP4_file_format" title="MP4 file format">-14</a></li> <li><a href="/wiki/MP4_file_format" title="MP4 file format">-17</a></li> <li><a href="/wiki/MP4_file_format" title="MP4 file format">-20</a></li></ul></li> <li><a href="/wiki/ISO_14617" title="ISO 14617">14617</a></li> <li><a href="/wiki/ISO_14644" title="ISO 14644">14644</a></li> <li><a href="/wiki/STEP-NC" title="STEP-NC">14649</a></li> <li><a href="/wiki/ISO/IEC_14651" title="ISO/IEC 14651">14651</a></li> <li><a href="/wiki/ISO_14698" title="ISO 14698">14698</a></li> <li><a href="/wiki/Software_maintenance" title="Software maintenance">14764</a></li> <li><a href="/wiki/C%2B%2B" title="C++">14882</a></li> <li><a href="/wiki/ISO_14971" title="ISO 14971">14971</a></li> <li><a href="/wiki/ISO_15022" title="ISO 15022">15022</a></li> <li><a href="/wiki/ISO_15189" title="ISO 15189">15189</a></li> <li><a href="/wiki/ISO/IEC_15288" title="ISO/IEC 15288">15288</a></li> <li><a href="/wiki/Ada_Semantic_Interface_Specification" title="Ada Semantic Interface Specification">15291</a></li> <li><a href="/wiki/ISO_15398" title="ISO 15398">15398</a></li> <li><a href="/wiki/Common_Criteria" title="Common Criteria">15408</a></li> <li><a href="/wiki/JPEG_2000" title="JPEG 2000">15444</a> <ul><li><a href="/wiki/Motion_JPEG_2000" title="Motion JPEG 2000">-3</a></li> <li><a href="/wiki/JPIP" title="JPIP">-9</a></li></ul></li> <li><a href="/wiki/HTML" title="HTML">15445</a></li> <li><a href="/wiki/PDF417" title="PDF417">15438</a></li> <li><a href="/wiki/ISO/IEC_15504" title="ISO/IEC 15504">15504</a></li> <li><a href="/wiki/International_Standard_Identifier_for_Libraries_and_Related_Organizations" title="International Standard Identifier for Libraries and Related Organizations">15511</a></li> <li><a href="/wiki/ISO_15686" title="ISO 15686">15686</a></li> <li><a href="/wiki/ISO/IEC_15693" title="ISO/IEC 15693">15693</a></li> <li><a href="/wiki/International_Standard_Audiovisual_Number" title="International Standard Audiovisual Number">15706</a> <ul><li><a href="/wiki/International_Standard_Audiovisual_Number" title="International Standard Audiovisual Number">-2</a></li></ul></li> <li><a href="/wiki/International_Standard_Musical_Work_Code" title="International Standard Musical Work Code">15707</a></li> <li><a href="/wiki/ISO/IEC_15897" title="ISO/IEC 15897">15897</a></li> <li><a href="/wiki/ISO_15919" title="ISO 15919">15919</a></li> <li><a href="/wiki/ISO_15924" title="ISO 15924">15924</a></li> <li><a href="/wiki/ISO_15926" title="ISO 15926">15926</a></li> <li><a href="/wiki/ISO_15926_WIP" title="ISO 15926 WIP">15926 WIP</a></li> <li><a href="/wiki/PDF/X" title="PDF/X">15930</a></li> <li><a href="/wiki/MPEG-7" title="MPEG-7">15938</a></li> <li><a href="/wiki/MaxiCode" title="MaxiCode">16023</a></li> <li><a href="/wiki/ECMAScript" title="ECMAScript">16262</a></li> <li><a href="/wiki/Quality_function_deployment" title="Quality function deployment">16355-1</a></li> <li><a href="/wiki/Mixed_raster_content" title="Mixed raster content">16485</a></li> <li><a href="/wiki/PDF/VT" title="PDF/VT">16612-2</a></li> <li><a href="/wiki/ISO_16750" title="ISO 16750">16750</a></li> <li><a href="/wiki/IATF_16949" title="IATF 16949">16949 (TS)</a></li> <li><a href="/wiki/ISO/IEC_17024" title="ISO/IEC 17024">17024</a></li> <li><a href="/wiki/ISO/IEC_17025" title="ISO/IEC 17025">17025</a></li> <li><a href="/wiki/ISO_17100" title="ISO 17100">17100</a></li> <li><a href="/wiki/Open_Virtualization_Format" title="Open Virtualization Format">17203</a></li> <li><a href="/wiki/SDMX" title="SDMX">17369</a></li> <li><a href="/wiki/Legal_Entity_Identifier" title="Legal Entity Identifier">17442</a></li> <li><a href="/wiki/COLLADA" title="COLLADA">17506</a></li> <li><a href="/wiki/ISO/IEC_27002" title="ISO/IEC 27002">17799</a></li> <li><a href="/wiki/QR_code" title="QR code">18004</a></li> <li><a href="/wiki/ISO/IEC_18014" title="ISO/IEC 18014">18014</a></li> <li><a href="/wiki/JPEG_XL" title="JPEG XL">18181</a></li> <li><a href="/wiki/ISO_18245" title="ISO 18245">18245</a></li> <li><a href="/wiki/Process_Specification_Language" title="Process Specification Language">18629</a></li> <li><a href="/wiki/Photographic_Activity_Test" title="Photographic Activity Test">18916</a></li> <li><a href="/wiki/PDF/A" title="PDF/A">19005</a></li> <li><a href="/wiki/ISO_19011" title="ISO 19011">19011</a></li> <li><a href="/wiki/ISO_19092" title="ISO 19092">19092</a> <ul><li><a href="/wiki/ISO_19092-1" class="mw-redirect" title="ISO 19092-1">-1</a></li> <li><a href="/wiki/ISO_19092-2" class="mw-redirect" title="ISO 19092-2">-2</a></li></ul></li> <li><a href="/wiki/ISO_19114" title="ISO 19114">19114</a></li> <li><a href="/wiki/Geospatial_metadata#ISO_19115:_Geographic_information_–_Metadata" title="Geospatial metadata">19115</a></li> <li><a href="/wiki/Simple_Features" title="Simple Features">19125</a></li> <li><a href="/wiki/Geography_Markup_Language#ISO_19136" title="Geography Markup Language">19136</a></li> <li><a href="/wiki/Shoe_size" title="Shoe size">19407</a></li> <li><a href="/wiki/ISO_19439" title="ISO 19439">19439</a></li> <li><a href="/wiki/Common_Object_Request_Broker_Architecture" title="Common Object Request Broker Architecture">19500</a></li> <li><a href="/wiki/Unified_Modeling_Language" title="Unified Modeling Language">19501</a></li> <li><a href="/wiki/Meta-Object_Facility" title="Meta-Object Facility">19502</a></li> <li><a href="/wiki/XML_Metadata_Interchange" title="XML Metadata Interchange">19503</a></li> <li><a href="/wiki/Unified_Modeling_Language" title="Unified Modeling Language">19505</a></li> <li><a href="/wiki/Knowledge_Discovery_Metamodel" title="Knowledge Discovery Metamodel">19506</a></li> <li><a href="/wiki/Object_Constraint_Language" title="Object Constraint Language">19507</a></li> <li><a href="/wiki/Meta-Object_Facility" title="Meta-Object Facility">19508</a></li> <li><a href="/wiki/XML_Metadata_Interchange" title="XML Metadata Interchange">19509</a></li> <li><a href="/wiki/Business_Process_Model_and_Notation" title="Business Process Model and Notation">19510</a></li> <li><a href="/wiki/ISO_19600" title="ISO 19600">19600</a></li> <li><a href="/wiki/ISO/IEC_19752" title="ISO/IEC 19752">19752</a></li> <li><a href="/wiki/RELAX_NG" title="RELAX NG">19757</a></li> <li><a href="/wiki/ISO/IEC_19770" title="ISO/IEC 19770">19770</a></li> <li><a href="/wiki/X3D" title="X3D">19775-1</a></li> <li><a href="/wiki/ISO/IEC_19794-5" title="ISO/IEC 19794-5">19794-5</a></li> <li><a href="/wiki/Cloud_Infrastructure_Management_Interface" title="Cloud Infrastructure Management Interface">19831</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">20000–29999</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/ISO/IEC_20000" title="ISO/IEC 20000">20000</a></li> <li><a href="/wiki/ISO_20022" title="ISO 20022">20022</a></li> <li><a href="/wiki/ISO_20121" title="ISO 20121">20121</a></li> <li><a href="/wiki/ISO_20400" title="ISO 20400">20400</a></li> <li><a href="/wiki/Open_Data_Protocol" title="Open Data Protocol">20802</a></li> <li><a href="/wiki/Han_Xin_code" title="Han Xin code">20830</a></li> <li><a href="/wiki/MPEG-21" title="MPEG-21">21000</a></li> <li><a href="/wiki/ISO_21001" title="ISO 21001">21001</a></li> <li><a href="/wiki/International_Standard_Text_Code" title="International Standard Text Code">21047</a></li> <li><a href="/wiki/JPEG_XS" title="JPEG XS">21122</a></li> <li><a href="/wiki/ISO_21500" title="ISO 21500">21500</a></li> <li><a href="/wiki/ISO/IEC_21827" title="ISO/IEC 21827">21827</a></li> <li><a href="/wiki/ISO_22000" title="ISO 22000">22000</a></li> <li><a href="/wiki/ECMAScript" title="ECMAScript">22275</a></li> <li><a href="/wiki/ISO_22300" title="ISO 22300">22300</a></li> <li><a href="/wiki/ISO_22301" title="ISO 22301">22301</a></li> <li><a href="/wiki/ISO_22395" title="ISO 22395">22395</a></li> <li><a href="/wiki/ECMAScript_for_XML" title="ECMAScript for XML">22537</a></li> <li><a href="/wiki/MPEG-A" title="MPEG-A">23000</a></li> <li><a href="/wiki/MPEG-D" title="MPEG-D">23003</a></li> <li><a href="/wiki/MPEG-H" title="MPEG-H">23008</a></li> <li><a href="/wiki/Dynamic_Adaptive_Streaming_over_HTTP" title="Dynamic Adaptive Streaming over HTTP">23009</a></li> <li><a href="/wiki/Versatile_Video_Coding" title="Versatile Video Coding">23090-3</a></li> <li><a href="/wiki/MPEG-G" title="MPEG-G">23092</a></li> <li><a href="/wiki/Essential_Video_Coding" title="Essential Video Coding">23094-1</a></li> <li><a href="/wiki/LCEVC" title="LCEVC">23094-2</a></li> <li><a href="/wiki/C_Sharp_(programming_language)" title="C Sharp (programming language)">23270</a></li> <li><a href="/wiki/Common_Language_Infrastructure" title="Common Language Infrastructure">23271</a></li> <li><a href="/wiki/Linux_Standard_Base" title="Linux Standard Base">23360</a></li> <li><a href="/wiki/Rectangular_Micro_QR_Code" title="Rectangular Micro QR Code">23941</a></li> <li><a href="/wiki/PDF/E" title="PDF/E">24517</a></li> <li><a href="/wiki/Lexical_Markup_Framework" title="Lexical Markup Framework">24613</a></li> <li><a href="/wiki/ISO-TimeML" title="ISO-TimeML">24617</a></li> <li><a href="/wiki/Common_Logic" title="Common Logic">24707</a></li> <li><a href="/wiki/MicroPDF417" title="MicroPDF417">24728</a></li> <li><a href="/wiki/ISO_25178" title="ISO 25178">25178</a></li> <li><a href="/wiki/ISO_25964" title="ISO 25964">25964</a></li> <li><a href="/wiki/ISO_26000" title="ISO 26000">26000</a></li> <li><a href="/wiki/ISO_26262" title="ISO 26262">26262</a></li> <li><a href="/wiki/OpenDocument" title="OpenDocument">26300</a></li> <li><a href="/wiki/Digital_object_identifier" title="Digital object identifier">26324</a></li> <li><a href="/wiki/ISO/IEC_27000_family" title="ISO/IEC 27000 family">27000 series</a></li> <li><a href="/wiki/ISO/IEC_27000" title="ISO/IEC 27000">27000</a></li> <li><a href="/wiki/ISO/IEC_27001" title="ISO/IEC 27001">27001</a></li> <li><a href="/wiki/ISO/IEC_27002" title="ISO/IEC 27002">27002</a></li> <li><a href="/wiki/ISO/IEC_27005" title="ISO/IEC 27005">27005</a></li> <li><a href="/wiki/ISO/IEC_27006" title="ISO/IEC 27006">27006</a></li> <li><a href="/wiki/International_Standard_Name_Identifier" title="International Standard Name Identifier">27729</a></li> <li><a href="/wiki/ISO_28000" title="ISO 28000">28000</a></li> <li>29110</li> <li><a href="/wiki/Requirements_engineering" title="Requirements engineering">29148</a></li> <li><a href="/wiki/JPEG_XR" title="JPEG XR">29199-2</a></li> <li><a href="/wiki/Office_Open_XML" title="Office Open XML">29500</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">30000+</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Ruby_(programming_language)" title="Ruby (programming language)">30170</a></li> <li><a href="/wiki/ISO_31000" title="ISO 31000">31000</a></li> <li><a href="/wiki/PDF" title="PDF">32000</a></li> <li><a href="/wiki/ISO_37001" title="ISO 37001">37001</a></li> <li><a href="/wiki/ISO/IEC_38500" title="ISO/IEC 38500">38500</a></li> <li><a href="/wiki/Graph_Query_Language" title="Graph Query Language">39075</a></li> <li><a href="/wiki/Web_Content_Accessibility_Guidelines" title="Web Content Accessibility Guidelines">40500</a></li> <li><a href="/wiki/ISO/IEC_42010" title="ISO/IEC 42010">42010</a></li> <li><a href="/wiki/ISO_45001" title="ISO 45001">45001</a></li> <li><a href="/wiki/ISO_50001" title="ISO 50001">50001</a></li> <li><a href="/wiki/ISO_55000" title="ISO 55000">55000</a></li> <li><a href="/wiki/ISO_56000" title="ISO 56000">56000</a></li> <li><a href="/wiki/ISO/IEC_80000" title="ISO/IEC 80000">80000</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" 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