Domain Name System and Hawker Hector: Difference between pages

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Revision as of 16:05, 26 June 2007

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{{infobox Aircraft

{{introrewrite}}

|name = Hector

|type = Army cooperation

|logo =

|manufacturer = [[Hawker Aircraft]]

|image = Image:hhector.jpg<!--in the ''image:filename'' format, no image tags-->

|caption = <!--image caption; if it isn't descriptive it should be left blank-->

|designer = <!--only appropriate for single designers, not project leaders-->

|first flight = [[14 February]] [[1936]]

|introduction = <!--date the aircraft entered or will enter military or revenue service-->

|retired = <!--date the aircraft left military or revenue service. If vague or multiples, it probably should be skipped-->

|status = <!--in most cases, this field is redundant; use it sparingly-->

|primary user = <!--please list only one, and don't use those tiny flags as they limit horizontal space-->

|more users = <!--limited to three "more users" total. please separate with <br/>-->

|produced = <!--years in production, e.g. 1970-1999, if still in active use but no longer built-->

|number built = 179

|unit cost =

|developed from = <!-- the aircraft which formed the basis for the topic type -->

|variants with their own articles = <!-- variants OF the topic type -->

}}

{{redir|DNS|other uses|DNS (disambiguation)}}

The '''Hawker Hector''' was intended as a replacement for the [[Hawker Audax]] Army co-operation aircraft. Because of the demand for [[Rolls-Royce Kestrel]] engines required for the [[Hawker Hind]] program, an alternative power plant was specified. Consequently the [[Napier & Son|Napier]] Dagger III was used.

{{IPstack}}

Although both the design and the building of the prototype was done by Hawkers, the subsequent production aircraft were built by [[Westland Aircraft]] in [[Yeovil]], Devon. The prototype first flew on on [[14 February]] [[1936]] with [["George" P.S.W. Bulman|George Bulman]] as pilot. One prototype and 178 production aircraft were built. Thirteen of these were supplied to [[Republic of Ireland|Eire]] in 1941-2.

On the [[Internet]], the '''Domain Name System''' (DNS) stores and associates many types of information with [[___domain name]]s; most importantly, it translates ___domain names (computer [[hostname]]s) to [[IP address]]es. It also lists [[mail exchange server]]s accepting [[e-mail]] for each ___domain. In providing a worldwide [[keyword]]-based redirection service, DNS is an essential component of contemporary [[Internet]] use.

The aircraft were later used by the [[Royal Air Force|RAF]] (in 1940) as target-towers, and for towing the [[General Aircraft Hotspur]] training glider.

DNS's most basic use is to translate [[hostname]]s to [[IP address]]s. It is in very simple terms like a phone book. For example, if you want to know the internet address of en.wikipedia.org, DNS can be used to tell you it's 66.230.200.100. DNS also has other important uses.

==Variants==

Pre-eminently, the DNS makes it possible to assign Internet destinations to the human organization or concern they represent, independently of the physical routing hierarchy represented by the numerical [[IP address]]. Because of this, hyperlinks and Internet contact information can remain the same, whatever the current IP routing arrangements may be, and can take a human-readable form (such as "<tt>wikipedia.org</tt>") which is rather easier to remember than an IP address (such as 66.230.200.100). People take advantage of this when they recite meaningful [[Uniform Resource Locator|URL]]s and [[e-mail address]]es without caring how the machine will actually locate them.

* '''Hector Mk I''' : Two-seat army co-operation aircraft for the RAF.

==Operators==

The DNS also distributes the responsibility for assigning ___domain names and mapping them to IP networks by allowing an authoritative server for each ___domain to keep track of its own changes, avoiding the need for a central registrar to be continually consulted and updated.

;{{IRL}}

* [[Irish Air Corps]]

;{{UK}}

* [[Royal Air Force]]

** [[No. 2 Squadron RAF]]

** [[No. 4 Squadron RAF]]

** [[No. 13 Squadron RAF]]

** [[No. 26 Squadron RAF]]

** [[No. 53 Squadron RAF]]

** [[No. 59 Squadron RAF]]

** [[No. 296 Squadron RAF]]

** [[No. 602 Squadron RAF]]

** [[No. 612 Squadron RAF]]

** [[No. 613 Squadron RAF]]

** [[No. 614 Squadron RAF]]

** [[No. 615 Squadron RAF]]

==Specifications (Hector) ==

{{aero-specs}}

{{aircraft specifications

<!-- if you do not understand how to use this template, please ask at [[Wikipedia talk:WikiProject Aircraft]] -->

|plane or copter?=<!-- options: plane/copter --> plane

|jet or prop?=<!-- options: jet/prop/both/neither --> prop

<!-- Now, fill out the specs. Please include units where appropriate (main comes first, alt in parentheses). If an item doesn't apply leave it blank. For instructions on using |more general=, |more performance=, |power original=, and |thrust original= see [[Template talk:Aircraft specifications]]. -->

|ref=Hawker Aircraft since 1920

|crew= Two

|capacity=

|length main= 29 ft 9½ in

|length alt= 9.06 m

|span main= 36 ft 11½ in

|span alt= 11.26 m

|height main= 10 ft 5 in

|height alt= 3.18 m

|area main= <!--ft²-->

|area alt= <!--m²-->

|airfoil=

|empty weight main= 3,389 lb

|empty weight alt= 1,537 kg

|loaded weight main= 4,910 lb

|loaded weight alt= 2,227 kg

|useful load main= <!--lb-->

|useful load alt= <!--kg-->

|max takeoff weight main= <!--lb-->

|max takeoff weight alt= <!--kg-->

|more general=

|engine (prop)= [[Napier Dagger]] III

|type of prop= 24-cylinder air-cooled [[H engine|H-block engine]]

|number of props=1

|power main= 1,000 hp

|power alt= 750 kW

|power original=

|max speed main= 162 knots

|max speed alt= 187 mph, 301 km/h

|max speed more= at 6,560 ft (1,999 m)

|cruise speed main= <!--knots-->

|cruise speed alt= <!--mph,km/h-->

|never exceed speed main= <!--knots-->

|never exceed speed alt= <!--mph,km/h-->

|stall speed main= <!--knots-->

|stall speed alt= <!--mph,km/h-->

|range main= <!--nm-->

|range alt= <!--mi,km-->

|ceiling main= 24,000 ft

|ceiling alt= 7,815 m

|climb rate main= <!--ft/min-->

|climb rate alt= <!--m/s-->

|loading main= <!--lb/ft²-->

|loading alt= <!--kg/m²-->

|thrust/weight= <!--aunitlessratio-->

|power/mass main= <!--hp/lb-->

|power/mass alt= <!--W/kg-->

|more performance=

|armament=

* 1 &times; forward-firing [[.303 British|.303 in]] [[Vickers machine gun]] Mk.V

* 1 &times; .303 in [[Lewis gun]] in the rear cockpit on a Hawker mount

* Mountings for a camera, flares, and two 112 lb (50 kg) bombs (or containers)

|avionics=

}}

== Reference ==

{{Reflist}}

* Francis K Mason, ''Hawker Aircraft since 1920'' (Putnam, 1961)

==DNSRelated in practicecontent==

{{aircontent|

When an application (such as a [[web browser]]) tries to find the IP address of a ___domain name, it doesn't necessarily follow all of the steps outlined in the ''Theory'' section above. We will first look at the concept of caching, and then outline the operation of DNS in "the real world."

|related=

|similar aircraft=

===Caching and time to live===

Because of the huge volume of requests generated by a system like the DNS, the designers wished to provide a mechanism to reduce the load on individual DNS servers. The mechanism devised provided that when a DNS resolver (i.e. client) received a DNS response, it would '''[[cache]]''' that response for a given period of time. A value (set by the administrator of the DNS server handing out the response) called the [[Time to live|time to live (TTL)]], defines that period of time. Once a response goes into cache, the resolver will consult its cached (stored) answer; only when the TTL expires (or when an administrator manually flushes the response from the resolver's memory) will the resolver contact the DNS server for the same information.

|sequence=[[Hawker Hartbees]] -

Generally, the Start of Authority (SOA) record specifies the time to live. The SOA record has the parameters:

[[Hawker Hurricane]] -

* '''Serial''' — the zone serial number, incremented when the [[zone file]] is modified, so the slave and secondary name servers know when the zone has been changed and should be reloaded.

[[Hawker Hector]] -

* '''Refresh''' — the number of seconds between update requests from secondary and slave name servers.

[[Hawker Henley]] -

* '''Retry''' — the number of seconds the secondary or slave will wait before retrying when the last attempt has failed.

[[Hawker Hotspur]] -

* '''Expire''' — the number of seconds a master or slave will wait before considering the data stale if it cannot reach the primary name server.

* '''Minimum''' — previously used to determine the minimum TTL, this offers negative caching.

|lists=

(Newer versions of [[BIND]] (<tt>named</tt>) will accept the suffixes 'M','H','D' or 'W', indicating a time-interval of minutes, hours, days and weeks respectively.)

|see also=[[List of aircraft of the Royal Air Force]]

===Caching time===

}}

As a noteworthy consequence of this distributed and caching architecture, changes to the DNS do not always take effect immediately and globally. This is best explained with an example: If an administrator has set a [[Time to live|TTL]] of 6 hours for the host <tt>www.wikipedia.org</tt>, and then changes the IP address to which <tt>www.wikipedia.org</tt> resolves at 12:01pm, the administrator must consider that a person who cached a response with the old IP address at 12:00pm will not consult the DNS server again until 6:00pm. The period between 12:01pm and 6:00pm in this example is called '''caching time''', which is best defined as a period of time that begins when you make a change to a DNS record and ends after the maximum amount of time specified by the [[Time to live|TTL]] expires. This essentially leads to an important logistical consideration when making changes to the DNS: ''not everyone is necessarily seeing the same thing you're seeing''. RFC 1537 helps to convey basic rules for how to set the TTL.

[[Category:British military reconnaissance aircraft 1930-1939]]

Note that the term "propagation", although very widely used, does not describe the effects of caching well. Specifically, it implies that [1] when you make a DNS change, it somehow spreads to all other DNS servers (instead, other DNS servers check in with yours as needed), and [2] that you do not have control over the amount of time the record is cached (you control the TTL values for all DNS records in your ___domain, except your NS records and any authoritative DNS servers that use your ___domain name).

[[Category:Hawker aircraft]]

Some resolvers may override TTL values, as the protocol supports caching for up to 68 years or no caching at all. Negative caching (the non-existence of records) is determined by name servers authoritative for a zone which MUST include the SOA record when reporting no data of the requested type exists. The MINIMUM field of the SOA record and the TTL of the SOA itself is used to establish the TTL for the negative answer. RFC 2308

Many people incorrectly refer to a mysterious 48 hour or 72 hour propagation time when you make a DNS change. When one changes the NS records for one's ___domain or the IP addresses for hostnames of authoritative DNS servers using one's ___domain (if any), there can be a lengthy period of time before all DNS servers use the new information. This is because those records are handled by the zone parent DNS servers (for example, the .com DNS servers if your ___domain is example.com), which typically cache those records for 48 hours. However, those DNS changes will be immediately available for any DNS servers that do not have them cached. And, any DNS changes on your ___domain other than the NS records and authoritative DNS server names can be nearly instantaneous, if you choose for them to be (by lowering the TTL once or twice ahead of time, and waiting until the old TTL expires before making the change).

===DNS in the real world===

[[Image:DNS in the real world.svg|right|thumb|400px|DNS resolving from program to OS-resolver to ISP-resolver to greater system.]]

Users generally do not communicate directly with a DNS resolver. Instead DNS resolution takes place transparently in client applications such as web browsers (like [[Opera (web browser)|Opera]], [[Mozilla Firefox]], [[Safari (web browser)|Safari]], [[Netscape Navigator]], [[Internet Explorer]], etc.), mail clients ([[Outlook Express]], [[Mozilla Thunderbird]], etc.), and other Internet applications. When a request is made which necessitates a DNS lookup, such programs send a resolution request to the local DNS resolver in the operating system which in turn handles the communications required.

The DNS resolver will almost invariably have a cache (see above) containing recent lookups. If the cache can provide the answer to the request, the resolver will return the value in the cache to the program that made the request. If the cache does not contain the answer, the resolver will send the request to a designated DNS server or servers. In the case of most home users, the [[internet service provider|Internet service provider]] to which the machine connects will usually supply this DNS server: such a user will either configure that server's address manually or allow [[Dynamic Host Configuration Protocol|DHCP]] to set it; however, where systems administrators have configured systems to use their own DNS servers, their DNS resolvers will generally point to their own nameservers. This name server will then follow the process outlined above in ''DNS in theory'', until it either successfully finds a result, or does not. It then returns its results to the DNS resolver; assuming it has found a result, the resolver duly caches that result for future use, and hands the result back to the software which initiated the request.

====Broken resolvers====

An additional level of complexity emerges when resolvers violate the rules of the DNS protocol. Some people have suggested that a number of large ISPs have configured their DNS servers to violate rules (presumably to allow them to run on less-expensive hardware than a fully compliant resolver), such as by disobeying TTLs, or by indicating that a ___domain name does not exist just because one of its name servers does not respond.

As a final level of complexity, some applications such as Web browsers also have their own DNS cache, in order to reduce the use of the DNS resolver library itself. This practice can add extra difficulty to DNS debugging, as it obscures which data is fresh, or lies in which cache. These caches typically have very short caching times of the order of one minute. A notable exception is [[Internet Explorer]]; recent versions cache DNS records for half an hour.<ref>{{cite web| url=http://support.microsoft.com/default.aspx?scid=KB;en-us;263558| title=How Internet Explorer uses the cache for DNS host entries| id=263558| publisher=Microsoft| year=2004| accessdate=2006-03-07}}</ref>

===Other DNS applications===

The system outlined above provides a somewhat simplified scenario. The DNS includes several other functions:

* Hostnames and IP addresses do not necessarily match on a one-to-one basis. Many hostnames may correspond to a single IP address: combined with [[virtual hosting]], this allows a single machine to serve many web sites. Alternatively a single hostname may correspond to many IP addresses: this can facilitate [[fault-tolerance|fault tolerance]] and load distribution, and also allows a site to move physical ___location seamlessly.

* There are many uses of DNS besides translating names to IP addresses. For instance, [[Mail transfer agent]]s use DNS to find out where to deliver [[e-mail]] for a particular address. The ___domain to mail exchanger mapping provided by [[MX record]]s accommodates another layer of fault tolerance and load distribution on top of the name to IP address mapping.

* [[Sender Policy Framework]] and [[DomainKeys]] instead of creating own record types were designed to take advantage of another DNS record type, the TXT record.

* To provide resilience in the event of computer failure, multiple DNS servers provide coverage of each ___domain. In particular, thirteen root servers exist worldwide. DNS programs or operating systems have the IP addresses of these servers built in. At least nominally, the [[United States|USA]] hosts all but three of the root servers. However, because many root servers actually implement [[anycast]], where many different computers can share the same IP address to deliver a single service over a large geographic region, most of the physical (rather than nominal) root servers now operate outside the USA.

The DNS uses [[Transmission Control Protocol|TCP]] and [[User Datagram Protocol|UDP]] on [[TCP and UDP port|port]] 53 to serve requests. Almost all DNS queries consist of a single UDP request from the client followed by a single UDP reply from the server. TCP typically comes into play only when the response data size exceeds 512 bytes, or for such tasks as [[DNS zone transfer|zone transfer]]. Some operating systems such as [[HP-UX]] are known to have resolver implementations that use TCP for all queries, even when UDP would suffice.

=== Extensions to DNS ===

[[EDNS]] is an extension of the DNS protocol which enhances the transport of DNS data in UDP packages, and adds support for expanding the space of request and response codes. It is described in RFC 2671.

=== Implementations of DNS ===

For a commented list of DNS server-side implementations, see [[Comparison of DNS server software]].

==Standards==

* RFC 882 Concepts and Facilities (Deprecated by RFC 1034)

* RFC 883 Domain Names: Implementation specification (Deprecated by RFC 1035)

* RFC 1032 Domain administrators guide

* RFC 1033 Domain administrators operations guide

* RFC 1034 Domain Names - Concepts and Facilities.

* RFC 1035 Domain Names - Implementation and Specification

* RFC 1101 DNS Encodings of Network Names and Other Types

* RFC 1123 Requirements for Internet Hosts -- Application and Support

* RFC 1183 New DNS RR Definitions

* RFC 1706 DNS NSAP Resource Records

* RFC 1876 Location Information in the DNS ([[LOC record|LOC]])

* RFC 1886 DNS Extensions to support [[IPv6|IP version 6]]

* RFC 1912 Common DNS Operational and Configuration Errors

* RFC 1995 Incremental Zone Transfer in DNS

* RFC 1996 A Mechanism for Prompt Notification of Zone Changes (DNS NOTIFY)

* RFC 2136 Dynamic Updates in the ___domain name system (DNS UPDATE)

* RFC 2181 Clarifications to the DNS Specification

* RFC 2182 Selection and Operation of Secondary DNS Servers

* RFC 2308 Negative Caching of DNS Queries (DNS NCACHE)

* RFC 2317 Classless IN-ADDR.ARPA delegation

* RFC 2671 Extension Mechanisms for DNS (EDNS0)

* RFC 2672 Non-Terminal DNS Name Redirection (DNAME record)

* RFC 2782 A DNS RR for specifying the ___location of services (DNS [[SRV record|SRV]])

* RFC 2845 Secret Key Transaction Authentication for DNS ([[TSIG]])

* RFC 2874 DNS Extensions to Support IPv6 Address Aggregation and Renumbering

* RFC 3403 Dynamic Delegation Discovery System (DDDS) ([[NAPTR]] records)

* RFC 3696 Application Techniques for Checking and Transformation of Names

* RFC 4398 Storing Certificates in the Domain Name System

* RFC 4408 [[Sender Policy Framework]] (SPF) (SPF records)

==Types of DNS records==

Important categories of data stored in the DNS include the following:

* An '''A record''' or '''address record''' maps a hostname to a 32-bit [[IPv4]] address.

* An '''AAAA record''' or '''[[IPv6]] address record''' maps a hostname to a 128-bit [[IPv6]] address.

* A '''CNAME record''' or '''[[FQDN|canonical name]] record''' is an alias of one name to another. The A record that the alias is pointing to can be either local or remote - on a foreign name server. This is useful when running multiple services (like an FTP ''and'' a webserver) from a single IP address. Each service can then have its own entry in DNS (like <tt>ftp.example.com</tt> and <tt>www.example.com<tt>.)

* An '''[[MX record]]''' or '''mail exchange record''' maps a ___domain name to a list of [[mail exchange server]]s for that ___domain.

* A '''PTR record''' or '''pointer record''' maps an [[IPv4]] address to the [[canonical name]] for that host. Setting up a PTR record for a hostname in the <tt>in-addr.arpa</tt> ___domain that corresponds to an IP address implements [[reverse DNS lookup]] for that address. For example (at the time of writing), <tt>www.icann.net</tt> has the IP address 192.0.34.164, but a PTR record maps <tt>164.34.0.192.in-addr.arpa</tt> to its canonical name, <tt>referrals.icann.org</tt>.

* An '''NS record''' or '''name server record''' maps a ___domain name to a list of DNS servers authoritative for that ___domain. Delegations depend on NS records.

* An '''SOA record''' or '''start of authority record''' specifies the DNS server providing ''authoritative'' information about an Internet ___domain, the email of the ___domain administrator, the ___domain serial number, and several timers relating to refreshing the zone.

* An '''[[SRV record]]''' is a generalized service ___location record.

* A '''[[TXT record]]''' allows an administrator to insert arbitrary text into a DNS record. For example, this record is used to implement the [[Sender Policy Framework]] and [[DomainKeys]] specifications.

* '''[[NAPTR record]]s''' ("Naming Authority Pointer") are a newer type of DNS record that support regular expression based rewriting.

Other types of records simply provide information (for example, a [[LOC record]] gives the physical ''___location'' of a host), or experimental data (for example, a '''WKS record''' gives a list of servers offering some ''well known service'' such as HTTP or POP3 for a ___domain).

==Internationalised ___domain names==

{{main|Internationalized ___domain name}}

While ___domain names in the DNS have no restrictions on the characters they use and can include non-[[ASCII]] characters, the same is not true for host names. Host names are the names most people see and use for things like e-mail and web browsing. Host names are restricted to a small subset of the ASCII character set that includes the [[Roman alphabet]] in upper and lower case, the digits 0 through 9, the dot, and the [[hyphen]]. (See RFC 3696 section 2 for details.) This prevented the representation of names and words of many languages natively. [[ICANN]] has approved the [[Punycode]]-based [[Internationalized ___domain name|IDNA]] system, which maps [[Unicode]] strings into the valid DNS character set, as a workaround to this issue. Some [[___domain name registry|registries]] have adopted IDNA.

== Security issues in DNS ==

DNS was not originally designed with security in mind, and thus has a number

of security issues.

DNS responses are traditionally not cryptographically signed, leading to

many attack possibilities; [[DNSSEC]] modifies DNS to add support for

cryptographically signed responses.

There are various extensions to support securing zone transfer information as well.

Some ___domain names can spoof other, similar-looking ___domain names. For example, "paypal.com" and "paypa1.com" are different names, yet users may be unable to tell the difference.

This problem is much more serious in systems that support internationalized ___domain names,

since many characters that are different (from the point of view of [[ISO 10646]])

appear identical on typical computer screens.

==Legal users of domains==

===Registrant===

No one in the world really "owns" a ___domain name except the [[Network Information Centre]] (NIC), or [[___domain name registry]].{{Fact|date=February 2007}} Most of the NICs in the world receive an annual fee from a legal user in order for the legal user to utilize the ___domain name (i.e. a sort of a leasing agreement exists, subject to the registry's terms and conditions). Depending on the various naming convention of the registries, legal users become commonly known as "registrants" or as "___domain holders".

[[ICANN]] holds a complete list of ___domain registries in the world. One can find the legal user of a ___domain name by looking in the [[WHOIS]] database held by most ___domain registries.

For most of the more than 240 [[country code top-level ___domain]]s (ccTLDs), the ___domain registries hold the authoritative WHOIS (Registrant, name servers, expiry dates etc.) For instance, [[DENIC]], Germany NIC holds the authoritative WHOIS to a .DE ___domain name.

However, some ___domain registries, such as for .COM, .ORG, .INFO, etc., use a registry-registrar model. There are hundreds of Domain Name Registrars that actually perform the ___domain name registration with the end-user (see lists at [http://www.icann.org/registrars/accredited-list.html ICANN] or [http://www.verisign.com/information-services/naming-services/com-net-registry/page_002166.html VeriSign]). By using this method of distribution, the registry only has to manage the relationship with the registrar, and the registrar maintains the relationship with the end-users, or 'registrants'. For .COM, .NET ___domain names, the ___domain registries, VeriSign holds a basic WHOIS (registrar and name servers etc.) One can find the detailed [[WHOIS]] (Registrant, [[name server]]s, expiry dates etc.) at the registrars.

Since about 2001, most [[gTLD]] registries (.ORG, .BIZ, .INFO) have adopted a so-called "thick" registry approach, i.e. keeping the authoritative [[WHOIS]] with the various registries instead of the registrars.

===Administrative contact===

A registrant usually designates an administrative contact to manage the ___domain name. In practice, the administrative contact usually has the most immediate power over a ___domain. Management functions delegated to the administrative contacts may include (for example):

* the obligation to conform to the requirements of the ___domain registry in order to retain the right to use a ___domain name

* authorization to update the physical address, e-mail address and telephone number etc. in [[WHOIS]]

===Technical contact===

A technical contact manages the name servers of a ___domain name. The many functions of a technical contact include:

* making sure the configurations of the ___domain name conforms to the requirements of the ___domain registry

* updating the ___domain zone

* providing the 24×7 functionality of the name servers (that leads to the accessibility of the ___domain name)

===Billing contact===

The party whom a [[Network Information Centre|NIC]] invoices.

===Name servers===

Namely the authoritative [[name server]]s that host the ___domain name zone of a ___domain name.

==Politics==

Many investigators have voiced criticism of the methods currently used to control ownership of domains. Critics commonly claim abuse by monopolies or near-monopolies, such as [[VeriSign]], Inc. Particularly noteworthy was the [[VeriSign]] [[Site Finder]] system which redirected all unregistered .com and .net domains to a [[VeriSign]] webpage. Despite widespread criticism, VeriSign only reluctantly removed it after [[ICANN]] threatened to revoke its contract to administer the root name servers.

There is also significant disquiet regarding [[United States]] political influence over the [[Internet Corporation for Assigned Names and Numbers|Internet Corporation for Assigned Names and Numbers (ICANN)]]. This was a significant issue in the attempt to create a .xxx [[Top-level ___domain]] and sparked greater interest in [[Alternative DNS root]]s that would be beyond the control of any single country.

===Truth in Domain Names Act===

In the [[United States]], the "Truth in Domain Names Act", in combination with the [[PROTECT Act of 2003|PROTECT Act]], forbids the use of a misleading ___domain name with the intention of attracting people into viewing a [[Internet pornography|visual depiction of sexually explicit conduct]] on the Internet.

==See also==

* [[Cybersquatting]]

* [[Domain hack]]

* [[Dynamic DNS]]

* [[DNS cache poisoning]]

* [[DNSSEC]]

* [[ICANN]]

* [[Root nameserver]]

* [[DNS hosting service]]

* [[DNS management software]]

* [[EveryDNS]]

* [[Geodomain]]

* [[NBNS#Name service|NBNS]]

* [[Network Information Service|NIS]]

* [[Hesiod (name service)|Hesiod]]

* [[OpenDNS]]

==References==

<references/>

==External links==

* {{dmoz|Computers/Internet/Protocols/DNS/Web_Tools|Web-based DNS tools}}

[[Category:Internet protocols]]

[[Category:___domain name system|*]]

[[Category:Application layer protocols]]

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