SherbyNet - /page/wikibook/entry.mu

Micron Document

<!DOCTYPE html>

<title>Root name server</title>

</head>

Root name server

</h1>

</header>

A root name server is a <a href="Name_server" title="Name server">name server</a> for the root zone of the Domain Name System (DNS) of the Internet. It directly answers requests for records in the root zone and answers other requests by returning a list of the authoritative name servers for the appropriate top-level domain (TLD). The root name servers are a critical part of the Internet infrastructure because they are the first step in resolving human-readable host names into IP addresses that are used in communication between Internet hosts.

A combination of limits in the DNS and certain protocols, namely the practical size of unfragmented User Datagram Protocol (UDP) packets, resulted in a decision to limit the number of root servers to thirteen server addresses.<a href="#cite_note-1">[1]</a><a href="#cite_note-2">[2]</a> The use of anycast addressing permits the actual number of root server instances to be much larger, and is 1,733 as of March 4, 2024.<a href="#cite_note-root-servers-org-3">[3]</a>

<div class="mw-heading mw-heading2"><h2 id="Root_domain">Root domain</h2></div>

The DNS is a hierarchical naming system for computers, services, or any resource participating in the Internet. The top of that hierarchy is the root domain. The root domain does not have a formal name and its label in the DNS hierarchy is an empty string. All fully qualified domain names (FQDNs) on the Internet can be regarded as ending with this empty string for the root domain, and therefore ending in a full stop character (the label delimiter), e.g., "<style data-mw-deduplicate="TemplateStyles:r886049734">

/* start https://en.wikipedia.org/ */

.mw-parser-output .monospaced{font-family:monospace,monospace}

/* end https://en.wikipedia.org/ */

</style>www.example.com.". This is generally implied rather than explicit, as modern DNS software does not actually require that the terminating dot be included when attempting to translate a domain name to an IP address.

The root domain contains all top-level domains of the Internet. As of July 2015, it contained 1058 TLDs, including 730 generic top-level domains (gTLDs) and 301 country code top-level domains (ccTLDs) in the root domain. In addition, the domain is used for technical name spaces in the management of Internet addressing and other resources. A domain is used for testing internationalized domain names.

<div class="mw-heading mw-heading2"><h2 id="Resolver_operation">Resolver operation</h2></div>

When a computer on the Internet needs to resolve a domain name, it uses <a href="Domain_Name_System#DNS_resolvers" title="Domain Name System">resolver</a> software to perform the lookup. A resolver breaks the name up into its labels from right to left. The first component (TLD) is queried using a root server to obtain the responsible authoritative server. Queries for each label return more specific name servers until a name server returns the answer of the original query.

In practice, most of this information does not change very often over a period of hours and therefore it is <a href="Cache_(computing)" title="Cache (computing)">cached</a> by intermediate name servers or by a name cache built into the user's application. DNS lookups to the root name servers may therefore be relatively infrequent. A survey in 2003 reported that only 2% of all queries to the root servers were legitimate. Incorrect or non-existent caching was responsible for 75% of the queries, 12.5% were for unknown TLDs, 7% were for lookups using IP addresses as if they were domain names, etc.<a href="#cite_note-4">[4]</a> Some misconfigured desktop computers even tried to update the root server records for the TLDs. A similar list of observed problems and recommended fixes has been published in RFC 4697.

Although any local implementation of DNS can implement its own private root name servers, the term "root name server" is generally used to describe the thirteen well-known root name servers that implement the root name space domain for the Internet's official global implementation of the Domain Name System. Resolvers use a small 3 <a href="Kilobyte" title="Kilobyte">KB</a> root.hints file published by Internic<a href="#cite_note-root_dataset-5">[5]</a> to bootstrap this initial list of root server addresses; in other words, root.hints is necessary to break the <a href="Circular_dependency" title="Circular dependency">circular dependency</a> of needing to know the addresses of a root name server to lookup the same address.

<div class="mw-heading mw-heading2"><h2 id="Root_server_addresses">Root server addresses</h2></div>

There are 13 logical root name servers specified, with logical names in the form letter.root-servers.net, where letter ranges from a to m. The choice of thirteen name servers was made because of limitations in the original DNS specification, which specifies a maximum packet size of 512 bytes when using the <a href="User_Datagram_Protocol" title="User Datagram Protocol">User Datagram Protocol</a> (UDP).<a href="#cite_note-6">[6]</a> Technically however, fourteen name servers fit into an IPv4 packet. The addition of IPv6 addresses for the root name servers requires more than 512 bytes, which is facilitated by the <a href="Extension_Mechanisms_for_DNS" title="Extension Mechanisms for DNS">EDNS0 extension</a> to the DNS standard.<a href="#cite_note-7">[7]</a>

This does not mean that there are only 13 physical servers; each operator uses redundant computer equipment to provide reliable service even if failure of hardware or software occurs. Additionally, all operate in multiple geographical locations using a routing technique called <a href="Anycast" title="Anycast">anycast</a> addressing, providing increased performance and even more fault tolerance. An informational homepage exists for every logical server (except G-Root) under the <a rel="nofollow" class="external text" href="https://root-servers.org/">Root Server Technical Operations Association</a> domain with web address in the form http://letter.root-servers.org/, where letter ranges from a to m.

Ten servers were originally in the United States; all are now operated using anycast addressing. Three servers were originally located in Stockholm (I-Root), Amsterdam (K-Root), and Tokyo (M-Root) respectively.

Older servers had their own name before the policy of using similar names was established. With anycast, most of the physical root servers are now outside the United States, allowing for high performance worldwide.

<th>Letter

</th>

<th><a href="IPv4" title="IPv4">IPv4</a> address

</th>

<th><a href="IPv6" title="IPv6">IPv6</a> address

</th>

<th><a href="Autonomous_system_(Internet)" title="Autonomous system (Internet)">AS-number</a><a href="#cite_note-root_org-8">[8]</a>

</th>

<th>Old name

</th>

<th>Operator

</th>

<th>Operator origin

</th>

<th>Location & no. of sites (global/local)<a href="#cite_note-9">[9]</a>

</th>

<th>Software

</th></tr>

<tr>

</th>

<td>198.41.0.4

</td>

<td>2001:503:ba3e::2:30

</td>

</td>

<td>ns.internic.net

</td>

<td><a href="Verisign" title="Verisign">Verisign</a>

</td>

<td> <a href="United_States" title="United States">United States</a>

</td>

<td>Distributed using <a href="Anycast" title="Anycast">anycast</a> 14/2

</td>

<td><a href="NSD" title="NSD">NSD</a> and Verisign ATLAS

</td></tr>

<tr>

</th>

</td>

</td>

</td>

<td>ns1.isi.edu

</td>

</td>

<td> <a href="United_States" title="United States">United States</a>

</td>

<td>Distributed using <a href="Anycast" title="Anycast">anycast</a> 6/0

</td>

</td></tr>

<tr>

</th>

<td>192.33.4.12

</td>

<td>2001:500:2::c

</td>

</td>

<td>c.psi.net

</td>

<td><a href="Cogent_Communications" title="Cogent Communications">Cogent Communications</a>

</td>

<td> <a href="United_States" title="United States">United States</a>

</td>

<td>Distributed using <a href="Anycast" title="Anycast">anycast</a> 10/0

</td>

</td></tr>

<tr>

</th>

</td>

<td>2001:500:2d::d

</td>

</td>

<td>terp.umd.edu

</td>

<td><a href="University_of_Maryland%2C_College_Park" title="University of Maryland, College Park">University of Maryland</a>

</td>

<td> <a href="United_States" title="United States">United States</a>

</td>

<td>Distributed using <a href="Anycast" title="Anycast">anycast</a> 22/127

</td>

</td></tr>

<tr>

</th>

<td>192.203.230.10

</td>

<td>2001:500:a8::e

</td>

</td>

<td>ns.nasa.gov

</td>

<td><a href="Ames_Research_Center" title="Ames Research Center">NASA Ames Research Center</a>

</td>

<td> <a href="United_States" title="United States">United States</a>

</td>

<td>Distributed using <a href="Anycast" title="Anycast">anycast</a> 117/137

</td>

</td></tr>

<tr>

</th>

<td>192.5.5.241

</td>

<td>2001:500:2f::f

</td>

</td>

<td>ns.isc.org

</td>

<td><a href="Internet_Systems_Consortium" title="Internet Systems Consortium">Internet Systems Consortium</a>

</td>

<td> <a href="United_States" title="United States">United States</a>

</td>

<td>Distributed using <a href="Anycast" title="Anycast">anycast</a> 119/119

</td>

<td><a href="BIND" title="BIND">BIND</a><a href="#cite_note-f-29">[24]</a> and Cloudflare <a href="#cite_note-30">[25]</a>

</td></tr>

<tr>

</th>

</td>

</td>

</td>

<td>ns.nic.ddn.mil

</td>

<td><a href="Defense_Information_Systems_Agency" title="Defense Information Systems Agency">Defense Information Systems Agency</a>

</td>

<td> <a href="United_States" title="United States">United States</a>

</td>

<td>Distributed using <a href="Anycast" title="Anycast">anycast</a> 6/0

</td>

</td></tr>

<tr>

</th>

</td>

</td>

</td>

<td>aos.arl.army.mil

</td>

<td><a href="United_States_Army_Research_Laboratory" title="United States Army Research Laboratory">U.S. Army Research Lab</a>

</td>

<td> <a href="United_States" title="United States">United States</a>

</td>

<td>Distributed using <a href="Anycast" title="Anycast">anycast</a> 8/0

</td>

</td></tr>

<tr>

</th>

<td>192.36.148.17

</td>

<td>2001:7fe::53

</td>

</td>

<td>nic.nordu.net

</td>

<td><a href="Netnod_Internet_Exchange_i_Sverige" class="mw-redirect" title="Netnod Internet Exchange i Sverige">Netnod</a>

</td>

<td> <a href="Sweden" title="Sweden">Sweden</a>

</td>

<td>Distributed using <a href="Anycast" title="Anycast">anycast</a> 63/2

</td>

</td></tr>

<tr>

</th>

</td>

<td>2001:503:c27::2:30

</td>

</td>

<td data-sort-value="" style="background: var(--background-color-interactive, #ececec); color: var(--color-base, inherit); vertical-align: middle; text-align: center;" class="table-na">—

</td>

<td><a href="Verisign" title="Verisign">Verisign</a>

</td>

<td> <a href="United_States" title="United States">United States</a>

</td>

<td>Distributed using <a href="Anycast" title="Anycast">anycast</a> 63/55

</td>

<td><a href="NSD" title="NSD">NSD</a> and Verisign ATLAS

</td></tr>

<tr>

</th>

<td>193.0.14.129

</td>

<td>2001:7fd::1

</td>

</td>

<td data-sort-value="" style="background: var(--background-color-interactive, #ececec); color: var(--color-base, inherit); vertical-align: middle; text-align: center;" class="table-na">—

</td>

</td>

<td> <a href="Netherlands" title="Netherlands">Netherlands</a>

</td>

<td>Distributed using <a href="Anycast" title="Anycast">anycast</a> 70/3

</td>

</td></tr>

<tr>

</th>

</td>

</td>

</td>

<td data-sort-value="" style="background: var(--background-color-interactive, #ececec); color: var(--color-base, inherit); vertical-align: middle; text-align: center;" class="table-na">—

</td>

<td><a href="ICANN" title="ICANN">ICANN</a>

</td>

<td> <a href="United_States" title="United States">United States</a>

</td>

<td>Distributed using <a href="Anycast" title="Anycast">anycast</a> 165/0

</td>

</td></tr>

<tr>

</th>

<td>202.12.27.33

</td>

<td>2001:dc3::35

</td>

</td>

<td data-sort-value="" style="background: var(--background-color-interactive, #ececec); color: var(--color-base, inherit); vertical-align: middle; text-align: center;" class="table-na">—

</td>

<td><a href="WIDE_Project" title="WIDE Project">WIDE Project</a>

</td>

<td> <a href="Japan" title="Japan">Japan</a>

</td>

<td>Distributed using <a href="Anycast" title="Anycast">anycast</a> 4/1

</td>

</td></tr></tbody></table>

There are also several alternative namespace systems with an <a href="Alternative_DNS_root" title="Alternative DNS root">alternative DNS root</a> using their own set of root name servers that exist in parallel to the mainstream name servers. The first, <a href="AlterNIC" title="AlterNIC">AlterNIC</a>, generated a substantial amount of press.

The function of a root name server may also be implemented locally, or on a provider network. Such servers are synchronized with the official root zone file <a rel="nofollow" class="external text" href="https://www.internic.net/zones/root.zone">as published</a> by <a href="ICANN" title="ICANN">ICANN</a>, and do not constitute an alternate root.

/* start https://en.wikipedia.org/ */

.mw-parser-output .ambox{border:1px solid #a2a9b1;border-left:10px solid #36c;background-color:#fbfbfb;box-sizing:border-box}.mw-parser-output .ambox+link+.ambox,.mw-parser-output .ambox+link+style+.ambox,.mw-parser-output .ambox+link+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+style+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+link+.ambox{margin-top:-1px}html body.mediawiki .mw-parser-output .ambox.mbox-small-left{margin:4px 1em 4px 0;overflow:hidden;width:238px;border-collapse:collapse;font-size:88%;line-height:1.25em}.mw-parser-output .ambox-speedy{border-left:10px solid #b32424;background-color:#fee7e6}.mw-parser-output .ambox-delete{border-left:10px solid #b32424}.mw-parser-output .ambox-content{border-left:10px solid #f28500}.mw-parser-output .ambox-style{border-left:10px solid #fc3}.mw-parser-output .ambox-move{border-left:10px solid #9932cc}.mw-parser-output .ambox-protection{border-left:10px solid #a2a9b1}.mw-parser-output .ambox .mbox-text{border:none;padding:0.25em 0.5em;width:100%}.mw-parser-output .ambox .mbox-image{border:none;padding:2px 0 2px 0.5em;text-align:center}.mw-parser-output .ambox .mbox-imageright{border:none;padding:2px 0.5em 2px 0;text-align:center}.mw-parser-output .ambox .mbox-empty-cell{border:none;padding:0;width:1px}.mw-parser-output .ambox .mbox-image-div{width:52px}@media(min-width:720px){.mw-parser-output .ambox{margin:0 10%}}@media print{body.ns-0 .mw-parser-output .ambox{display:none!important}}

/* end https://en.wikipedia.org/ */

</style>

As the root name servers are an important part of the Internet, they have come <a href="DNS_Backbone_DDoS_Attacks" class="mw-redirect" title="DNS Backbone DDoS Attacks">under attack</a> several times, although none of the attacks have ever been serious enough to severely affect the performance of the Internet.

<div class="mw-heading mw-heading2"><h2 id="Root_server_supervision">Root server supervision</h2></div>

The DNS Root Server System Advisory Committee is an <a href="ICANN" title="ICANN">ICANN</a> committee. ICANN's bylaws<a href="#cite_note-54">[41]</a> say the committee provides advice to ICANN but the committee claims no authority over the servers or server operators.

The root zone file is a small (about 2 <a href="Megabyte" title="Megabyte">MB</a>) data set<a href="#cite_note-root_dataset-5">[5]</a> whose publication is the primary purpose of root name servers. This is not to be confused with the root.hints file used to bootstrap a resolver.

The root zone file is at the apex of a hierarchical distributed database called the <a href="Domain_Name_System" title="Domain Name System">Domain Name System</a> (DNS). This database is used by almost all Internet applications to translate worldwide unique names such as www.wikipedia.org into other identifiers such as <a href="IP_address" title="IP address">IP addresses</a>.

The contents of the root zone file is a list of names and numeric IP addresses of the root domain <a href="Name_server" title="Name server">authoritative DNS servers</a> for all <a href="Top-level_domains" class="mw-redirect" title="Top-level domains">top-level domains</a> (TLDs) such as com, org, edu, and the <a href="Country_code_top-level_domain" title="Country code top-level domain">country code top-level domains</a> (it also includes that info for root domain, the dot). On 12 December 2004, 773 different authoritative servers for the TLDs were listed. Later the number of TLDs increased greatly. As of July 2020, the root zone consisted of 1511 useful TLDs (excluded are: 55 domains that are not assigned, 8 that are retired, and 11 test domains). Other name servers forward queries for which they do not have any information about authoritative servers to a root name server. The root name server, using its root zone file, answers with a referral to the authoritative servers for the appropriate TLD or with an indication that no such TLD exists.<a href="#cite_note-55">[42]</a>

/* start https://en.wikipedia.org/ */

.mw-parser-output .portalbox{padding:0;margin:0.5em 0;display:table;box-sizing:border-box;max-width:175px;list-style:none}.mw-parser-output .portalborder{border:1px solid var(--border-color-base,#a2a9b1);padding:0.1em;background:var(--background-color-neutral-subtle,#f8f9fa)}.mw-parser-output .portalbox-entry{display:table-row;font-size:85%;line-height:110%;height:1.9em;font-style:italic;font-weight:bold}.mw-parser-output .portalbox-image{display:table-cell;padding:0.2em;vertical-align:middle;text-align:center}.mw-parser-output .portalbox-link{display:table-cell;padding:0.2em 0.2em 0.2em 0.3em;vertical-align:middle}@media(min-width:720px){.mw-parser-output .portalleft{margin:0.5em 1em 0.5em 0}.mw-parser-output .portalright{clear:right;float:right;margin:0.5em 0 0.5em 1em}}

/* end https://en.wikipedia.org/ */

</style>

<ul><li><a href="Blackhole_server" title="Blackhole server">Blackhole server</a></li>

<li><a href="Distributed_denial-of-service_attacks_on_root_nameservers" title="Distributed denial-of-service attacks on root nameservers">Distributed denial-of-service attacks on root nameservers</a></li>

<li><a href="Extension_Mechanisms_for_DNS" title="Extension Mechanisms for DNS">Extension Mechanisms for DNS</a> (Extended DNS, version 0)</li>

<li><a href="Internet_backbone" title="Internet backbone">Internet backbone</a></li>

<li><a href="Open_Root_Server_Network" title="Open Root Server Network">Open Root Server Network</a></li>

<div class="mw-heading mw-heading2"><h2 id="Notes">Notes</h2></div>

/* start https://en.wikipedia.org/ */

.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}

/* end https://en.wikipedia.org/ */

</style><div class="reflist">

<li id="cite_note-10"><a href="#cite_ref-10">^</a> <a rel="nofollow" class="external text" href="https://stat.ripe.net/widget/bgplay#w.resource=AS19836&w.ignoreReannouncements=true&w.rrcs=0,1,6,7,11,14,3,4,5,10,12,13,15&w.starttime=1356998400&w.endtime=1389250800&w.instant=null&w.type=bgp">AS19836</a> is not listed by the RIPEstat tool, though one can see it in <a rel="nofollow" class="external free" href="https://stat.ripe.net/AS19836#tabId=at-a-glance">https://stat.ripe.net/AS19836#tabId=at-a-glance</a>

</li>

<li id="cite_note-11"><a href="#cite_ref-11">^</a> <a rel="nofollow" class="external text" href="http://www.ris.ripe.net/cgi-bin/riswhois.cgi?address=198.41.0.4&matchtype=L&submit=Query+RISwhois">AS64820</a> is listed as "private use" in RIPE's RISwhois tool

</li>

<li id="cite_note-18"><a href="#cite_ref-18">^</a> Originally it was 128.9.0.107; on 29 January 2004, it was changed to 192.228.79.201.<a href="#cite_note-14">[12]</a> On 24 October 2017, it was changed to 199.9.14.201.<a href="#cite_note-iana-list-13">[11]</a><a href="#cite_note-15">[13]</a> On 27 November 2023 it was changed to 170.247.170.2, which is the current address.<a href="#cite_note-b-change-2023-usc-16">[14]</a><a href="#cite_note-b-change-2023-lacnic-17">[15]</a>

</li>

<li id="cite_note-22"><a href="#cite_ref-22">^</a> Since 3 January 2013; originally was 128.8.10.90.

</li>

<li id="cite_note-24"><a href="#cite_ref-24">^</a> Since November 2017; originally was AS27.

</li>

<li id="cite_note-31"><a href="#cite_ref-31">^</a> Formerly <a rel="nofollow" class="external text" href="https://web.archive.org/web/20110621074912/http://www.nic.mil/">http://www.nic.mil/ (Internet Archive link)</a>; unlike all other DNS root servers, G-Root does not implement a homepage under root-servers.org, i.e. <a rel="nofollow" class="external text" href="http://g.root-servers.org/">http://g.root-servers.org/</a>.

</li>

<li id="cite_note-noping-32">^ <a href="#cite_ref-noping_32-0">a</a> <a href="#cite_ref-noping_32-1">b</a> Unlike all other DNS root servers, G-Root does not respond to <a href="Ping_(networking_utility)" title="Ping (networking utility)">pings</a>.

</li>

<li id="cite_note-34"><a href="#cite_ref-34">^</a> Since 1 December 2015; originally was 128.63.2.53.

</li>

<li id="cite_note-36"><a href="#cite_ref-36">^</a> Since 1 December 2015; originally was 2001:500:1::803f:235.

</li>

<li id="cite_note-37"><a href="#cite_ref-37">^</a> Since 1 December 2015; originally was AS13.

</li>

<li id="cite_note-40"><a href="#cite_ref-40">^</a> Since November 2002; originally was 198.41.0.10.

</li>

<li id="cite_note-45"><a href="#cite_ref-45">^</a> Since 1 November 2007; originally was 198.32.64.12.

</li>

<li id="cite_note-47"><a href="#cite_ref-47">^</a> Since 23 March 2016; originally was 2001:500:3::42.

</li>

</ol></div></div>

<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>

/* start https://en.wikipedia.org/ */

.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("./mw/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("./mw/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("./mw/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("./mw/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}}

/* end https://en.wikipedia.org/ */

</style><cite id="CITEREFMark_Andrews,_ISC2011" class="citation mailinglist cs1">Mark Andrews, <a href="Internet_Systems_Consortium" title="Internet Systems Consortium">ISC</a> (11 November 2011). <a rel="nofollow" class="external text" href="https://lists.isc.org/pipermail/bind-users/2011-November/085653.html">"Reason for Limited number of Root DNS Servers"</a>. bind-users (Mailing list). Retrieved 8 January 2016.</cite>

</li>

<li id="cite_note-2"><a href="#cite_ref-2">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.netnod.se/dns/dns-root-server-faq">"DNS root server FAQ"</a>. <a href="Netnod" title="Netnod">Netnod</a>. Retrieved 18 January 2016.</cite>

</li>

<li id="cite_note-root-servers-org-3"><a href="#cite_ref-root-servers-org_3-0">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://root-servers.org/">"root-servers.org"</a>. Retrieved 4 March 2024.</cite>

</li>

<li id="cite_note-4"><a href="#cite_ref-4">^</a> <cite id="CITEREFDuane_WesselsMarina_Fomenkov2003" class="citation web cs1">Duane Wessels; Marina Fomenkov (2003). <a rel="nofollow" class="external text" href="http://dns.measurement-factory.com/writings/wessels-pam2003-paper.pdf">"Wow, That's a Lot of Packets"</a> (PDF). Retrieved 7 November 2013.</cite>

</li>

<li id="cite_note-root_dataset-5">^ <a href="#cite_ref-root_dataset_5-0">a</a> <a href="#cite_ref-root_dataset_5-1">b</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.iana.org/domains/root/files">"IANA – Root Files"</a>. www.iana.org. Retrieved 10 July 2019.</cite>

</li>

<li id="cite_note-6"><a href="#cite_ref-6">^</a> RFC 1035 Domain names – implementation and specification

</li>

<li id="cite_note-7"><a href="#cite_ref-7">^</a> <a rel="nofollow" class="external text" href="https://www.icann.org/en/system/files/files/sac-018-en.pdf">ICANN: Accommodating IP Version 6 Address Resource Records for the Root of the Domain Name System</a>

</li>

<li id="cite_note-root_org-8">^ <a href="#cite_ref-root_org_8-0">a</a> <a href="#cite_ref-root_org_8-1">b</a> <a href="#cite_ref-root_org_8-2">c</a> <a href="#cite_ref-root_org_8-3">d</a> <a href="#cite_ref-root_org_8-4">e</a> <a href="#cite_ref-root_org_8-5">f</a> <a href="#cite_ref-root_org_8-6">g</a> <a href="#cite_ref-root_org_8-7">h</a> <a href="#cite_ref-root_org_8-8">i</a> <a href="#cite_ref-root_org_8-9">j</a> <a href="#cite_ref-root_org_8-10">k</a> <a href="#cite_ref-root_org_8-11">l</a> AS-numbers and IP-addresses from <a rel="nofollow" class="external text" href="https://root-servers.org/">Root-servers.org homepage</a> checked 9 January 2014

</li>

<li id="cite_note-9"><a href="#cite_ref-9">^</a> Location and sites from <a rel="nofollow" class="external text" href="http://root-servers.org/">Root-servers.org homepage</a> checked 10 October 2014

</li>

<li id="cite_note-RISwhois_A-12"><a href="#cite_ref-RISwhois_A_12-0">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.ris.ripe.net/cgi-bin/riswhois.cgi?address=198.41.0.4&matchtype=L&submit=Query+RISwhois">"RIS – RIPE Network Coordination Centre"</a>. Ris.ripe.net. Retrieved 23 January 2014.</cite>

</li>

<li id="cite_note-iana-list-13">^ <a href="#cite_ref-iana-list_13-0">a</a> <a href="#cite_ref-iana-list_13-1">b</a> <a href="#cite_ref-iana-list_13-2">c</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.iana.org/domains/root/servers">"List of Root Servers"</a>.</cite>

</li>

<li id="cite_note-14"><a href="#cite_ref-14">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://b.root-servers.org/news/2004/02/02/new-ipv4.html">"New IPv4 address for b.root-servers.net"</a>. b.root-servers.org. 2 February 2004. Retrieved 23 October 2023.</cite>

</li>

<li id="cite_note-15"><a href="#cite_ref-15">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://b.root-servers.org/news/2017/08/09/new-ipv4.html">"B-Root's IPv4 address to be renumbered 2017-10-24"</a>. b.root-servers.org. 9 August 2017. Retrieved 23 October 2023.</cite>

</li>

<li id="cite_note-b-change-2023-usc-16"><a href="#cite_ref-b-change-2023-usc_16-0">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://b.root-servers.org/news/2023/05/16/new-addresses.html">"New addresses for b.root-servers.net"</a>. b.root-servers.org. 16 May 2023. Retrieved 23 October 2023.</cite>

</li>

<li id="cite_note-b-change-2023-lacnic-17"><a href="#cite_ref-b-change-2023-lacnic_17-0">^</a> <cite class="citation web cs1 cs1-prop-foreign-lang-source"><a rel="nofollow" class="external text" href="https://www.lacnic.net/6868/1/lacnic/lacnic-asigna-recursos-de-numeracion-al-servidor-raiz-de-usc_isi">"LACNIC asigna recursos de numeración al servidor raíz de USC/ISI"</a> [LACNIC assigns numbering resources to the USC/ISI root server]. www.lacnic.net (in Spanish). 30 May 2023. Retrieved 23 October 2023.</cite>

</li>

<li id="cite_note-19"><a href="#cite_ref-19">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://root-servers.org/">"Root Server Technical Operations Assn"</a>. root-servers.org. 7 August 2017. Retrieved 7 August 2017.</cite>

</li>

<li id="cite_note-20"><a href="#cite_ref-20">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://b.root-servers.org/news/2021/02/18/bind-and-knot.html">"B-Root Software Diversity With Bind and Knot"</a>. <a href="University_of_Southern_California" title="University of Southern California">USC</a>-<a href="Information_Sciences_Institute" title="Information Sciences Institute">ISI</a>. 18 February 2021. Retrieved 21 February 2021.</cite>

</li>

<li id="cite_note-21"><a href="#cite_ref-21">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.ris.ripe.net/cgi-bin/riswhois.cgi?address=192.33.4.12&matchtype=L&submit=Query+RISwhois">"RIS – RIPE Network Coordination Centre"</a>. Ris.ripe.net. 13 October 2013. Retrieved 23 January 2014.</cite>

</li>

<li id="cite_note-23"><a href="#cite_ref-23">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20130310100321/http://d.root-servers.org/renumber.html">"D-Root is Changing its IPv4 Address on 3 January 2013"</a>. Archived from <a rel="nofollow" class="external text" href="http://d.root-servers.org/renumber.html">the original</a> on 10 March 2013. Retrieved 16 December 2012.</cite>

</li>

<li id="cite_note-25"><a href="#cite_ref-25">^</a> <a rel="nofollow" class="external text" href="http://www.ris.ripe.net/cgi-bin/riswhois.cgi?address=199.7.91.13&matchtype=L&submit=Query+RISwhois">RISwhois</a>, excluding less-specific AS3303 route announcement

</li>

<li id="cite_note-d-26"><a href="#cite_ref-d_26-0">^</a> <a rel="nofollow" class="external text" href="http://d.root-servers.org/history.html">D-root History page</a>

</li>

<li id="cite_note-RISwhois_E-27"><a href="#cite_ref-RISwhois_E_27-0">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.ris.ripe.net/cgi-bin/riswhois.cgi?address=192.203.230.10&matchtype=L&submit=Query+RISwhois">"RIS – RIPE Network Coordination Centre"</a>. Ris.ripe.net. Retrieved 30 October 2017.</cite>

</li>

<li id="cite_note-RISwhois_F-28"><a href="#cite_ref-RISwhois_F_28-0">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.ris.ripe.net/cgi-bin/riswhois.cgi?address=192.5.5.241&matchtype=L&submit=Query+RISwhois">"RIS – RIPE Network Coordination Centre"</a>. Ris.ripe.net. Retrieved 23 January 2014.</cite>

</li>

<li id="cite_note-f-29"><a href="#cite_ref-f_29-0">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20130325180234/http://www.isc.org/community/f-root">"F-root | Internet Systems Consortium"</a>. Archived from <a rel="nofollow" class="external text" href="https://www.isc.org/community/f-root/">the original</a> on 25 March 2013. Retrieved 9 September 2009.</cite>

</li>

<li id="cite_note-30"><a href="#cite_ref-30">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://blog.cloudflare.com/f-root/">"Delivering Dot"</a>.</cite>

</li>

<li id="cite_note-33"><a href="#cite_ref-33">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.ris.ripe.net/cgi-bin/riswhois.cgi?address=192.112.36.4&matchtype=L&submit=Query+RISwhois">"RIS – RIPE Network Coordination Centre"</a>. Ris.ripe.net. 18 September 2013. Retrieved 23 January 2014.</cite>

</li>

<li id="cite_note-hrootchange-35">^ <a href="#cite_ref-hrootchange_35-0">a</a> <a href="#cite_ref-hrootchange_35-1">b</a> <a href="#cite_ref-hrootchange_35-2">c</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.ietf.org/mail-archive/web/dnsop/current/msg15330.html">"Advance notice – H-root address change on December 1, 2015"</a>. DNSOP. 31 August 2015. Retrieved 19 February 2018.</cite>

</li>

<li id="cite_note-38"><a href="#cite_ref-38">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.ris.ripe.net/cgi-bin/riswhois.cgi?address=128.63.2.53&matchtype=L&submit=Query+RISwhois">"RIS – RIPE Network Coordination Centre"</a>. Ris.ripe.net. 2 January 2014. Retrieved 23 January 2014.</cite>

</li>

<li id="cite_note-39"><a href="#cite_ref-39">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.ris.ripe.net/cgi-bin/riswhois.cgi?address=192.36.148.17&matchtype=L&submit=Query+RISwhois">"RIS – RIPE Network Coordination Centre"</a>. Ris.ripe.net. Retrieved 23 January 2014.</cite>

</li>

<li id="cite_note-RISwhois_J-41">^ <a href="#cite_ref-RISwhois_J_41-0">a</a> <a href="#cite_ref-RISwhois_J_41-1">b</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.ris.ripe.net/cgi-bin/riswhois.cgi?address=192.58.128.30&matchtype=L&submit=Query+RISwhois">"RIS – RIPE Network Coordination Centre"</a>. Ris.ripe.net. Retrieved 23 January 2014.</cite>

</li>

<li id="cite_note-42"><a href="#cite_ref-42">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.ris.ripe.net/cgi-bin/riswhois.cgi?address=193.0.14.129&matchtype=L&submit=Query+RISwhois">"RIS – RIPE Network Coordination Centre"</a>. Ris.ripe.net. 20 June 2013. Retrieved 23 January 2014.</cite>

</li>

<li id="cite_note-43"><a href="#cite_ref-43">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.peeringdb.com/asn/25152">"Peering Networks Detailed View"</a>. Peeringdb.com. 21 October 2013. Retrieved 23 January 2014.</cite>

</li>

<li id="cite_note-k-44"><a href="#cite_ref-k_44-0">^</a> <a rel="nofollow" class="external text" href="http://k.root-servers.org/">K-root Homepage</a>

</li>

<li id="cite_note-46"><a href="#cite_ref-46">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.icann.org/news/blog/advisory-l-root-changing-ip-address-on-1st-november">"Advisory — "L Root" changing IP address on 1 November"</a>. <a href="ICANN" title="ICANN">ICANN</a>.</cite>

</li>

<li id="cite_note-48"><a href="#cite_ref-48">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20160422133507/http://www.dns.icann.org/2015/11/05/l-root-ipv6-renumbering/">"L-Root IPv6 Renumbering"</a>. <a href="ICANN" title="ICANN">ICANN</a>. Archived from <a rel="nofollow" class="external text" href="http://www.dns.icann.org/2015/11/05/l-root-ipv6-renumbering/">the original</a> on 22 April 2016.</cite>

</li>

<li id="cite_note-49"><a href="#cite_ref-49">^</a> <a rel="nofollow" class="external autonumber" href="http://www.ris.ripe.net/cgi-bin/riswhois.cgi?address=199.7.83.42&matchtype=L&submit=Query+RISwhois">[1]</a>, excluding less-specific AS3303 route announcement

</li>

<li id="cite_note-50"><a href="#cite_ref-50">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.peeringdb.com/asn/20144">"Peering Networks Detailed View"</a>. Peeringdb.com. 15 April 2013. Retrieved 23 January 2014.</cite>

</li>

<li id="cite_note-l-51"><a href="#cite_ref-l_51-0">^</a> <a rel="nofollow" class="external text" href="http://l.root-servers.org/">l.root-servers.net</a>

</li>

<li id="cite_note-52"><a href="#cite_ref-52">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.ris.ripe.net/cgi-bin/riswhois.cgi?address=202.12.27.33&matchtype=L&submit=Query+RISwhois">"RIS – RIPE Network Coordination Centre"</a>. Ris.ripe.net. 21 October 2013. Retrieved 23 January 2014.</cite>

</li>

<li id="cite_note-53"><a href="#cite_ref-53">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.peeringdb.com/asn/7500">"Peering Networks Detailed View"</a>. Peeringdb.com. 23 December 2013. Retrieved 23 January 2014.</cite>

</li>

<li id="cite_note-54"><a href="#cite_ref-54">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.icann.org/resources/pages/governance/bylaws-en#XI-2.3">"BYLAWS FOR INTERNET CORPORATION FOR ASSIGNED NAMES AND NUMBERS | A California Nonprofit Public-Benefit Corporation – ICANN"</a>. www.icann.org. Retrieved 10 July 2019.</cite>

</li>

<li id="cite_note-55"><a href="#cite_ref-55">^</a> ISOC, DNS Root Name Servers explained for the non-expert, (<a rel="nofollow" class="external text" href="https://www.internetsociety.org/resources/doc/2004/the-internet-domain-name-system-explained-for-non-experts-by-daniel-karrenberg/">Available online</a>, accessed 19 March 2010.)

</li>

</ol></div></div>

<div class="mw-heading mw-heading2"><h2 id="Further_reading">Further reading</h2></div>

<ul><li><a rel="nofollow" class="external text" href="https://root-servers.org/">Root Server Technical Operations Association</a></li>

<li><a rel="nofollow" class="external text" href="https://www.iana.org/domains/root/servers">List of Root Servers, IANA</a></li>

<li><a rel="nofollow" class="external text" href="https://www.circleid.com/posts/dns_root_servers_google_maps/">Root Servers' Geographical Locations on Google Maps</a></li>

<li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20030927191521/http://www.rssac.org/">DNS Root Server System Advisory Committee</a></li>

<li><a rel="nofollow" class="external text" href="https://www.internetsociety.org/resources/doc/2004/the-internet-domain-name-system-explained-for-non-experts-by-daniel-karrenberg/">DNS Root Name Servers Explained For Non-Experts</a></li>

<li><a rel="nofollow" class="external text" href="https://www.internetsociety.org/briefings/020/">DNS Root Name Servers Frequently Asked Questions</a></li>

<li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20051229123012/http://www.apnic.net/services/rootserver/">Location of Root servers in Asia-Pacific</a></li>

<li><a rel="nofollow" class="external text" href="https://www.bind9.net/dnshealth/">Bogus Queries received at the Root Servers</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20060821195930/http://www.bind9.net/dnshealth/">Archived</a> 21 August 2006 at the <a href="Wayback_Machine" title="Wayback Machine">Wayback Machine</a></li>

<li>RFC <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc2826">2826</a> – IAB Technical Comment on the Unique DNS Root</li>

<li>RFC <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc2870">2870</a> – Root Name Server Operational Requirements</li>

<li>RFC <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc4697">4697</a> – Observed DNS Resolution Misbehavior (from observations on the Root Servers)</li>

<li><a rel="nofollow" class="external text" href="https://project-is-offline.orsn.net/">ORSN, Open Root Server Network – an unrelated, competing DNS-based name infrastructure</a></li>

<li><a rel="nofollow" class="external text" href="https://www.icann.org/en/system/files/files/rssac-023-04nov16-en.pdf">RSSAC023, about the origins</a></li></ul>

<div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2></div>

<ul><li><a rel="nofollow" class="external text" href="https://root-servers.org/">Root Server Technical Operations Association</a></li>

<li><a rel="nofollow" class="external text" href="https://www.iana.org/domains/root/files">Root Files, IANA</a></li>

<li><a rel="nofollow" class="external text" href="https://project-is-offline.orsn.net/">orsn.org Open Root Server Network</a></li>

<li><a rel="nofollow" class="external text" href="https://www.internic.net/domain/root-servers.net.zone">root-servers.net.zone</a></li>

<li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20070606075755/http://private.dnsstuff.com/info/roottimes.htm">Root Server response times</a></li>

<li><a rel="nofollow" class="external text" href="https://www.internetsociety.org/resources/doc/2004/the-internet-domain-name-system-explained-for-non-experts-by-daniel-karrenberg/">DNS root nameservers explained for non-experts</a></li></ul></div><div><div class="zim-footer">

This article is issued from <a class="external text" title="Last edited on 2025-06-05" href="https://en.wikipedia.org/wiki/?title=Root_name_server&oldid=1294029150">Wikipedia</a>. The text is available under <a class="external text" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en">Creative Commons Attribution-Share Alike 4.0</a> unless otherwise noted. Additional terms may apply for the media files.

</div>

</div></div>

</div>

</main>

</div>

</body></html>