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Neustar Registry TLD Glossary

Defining the first step in your Digital Identity


AGP (Add Grace Period):

The period following the initial registration of a domain name, typically lasting five days, during which the registration can be reversed, and credit issued to a registrar. It appears as a contractual term in some gTLD registry agreements.

Once a domain name is deleted by the registry at this stage, it is immediately available for registration by any registrant through any registrar. AGP was intended to allow for the no-cost cancellation of domain name registrations resulting from typos and other errors by registrars and registrants as well as some types of fraudulent registrations.

APOC (Abuse Point of Contact):

A single point of contact required to be published for every registry’s website, to enable users to notify registry operators of abusive behavior about their TLD(s). Contact details should include email and snail mail addresses for the primary contact person who handles such inquiries.


An entity that has applied to ICANN for the rights to operate a particular domain name, but has not yet executed its Registry Agreement with ICANN.

Applicant Guidebook:

The Guidebook is an overview of the policies and procedures governing the 2012 new gTLD Application Round. It specifies the documents and information that must be provided, the financial and legal commitments of operating a gTLD, and the application and evaluation processes.

ASCII (American Standard Code for Information Interchange):

A character encoding based on the English alphabet; domains in ASCII-script are limited to the letters A to Z, the digits 0 to 9, and the hyphen in domain names.


A method of resolving string contention sets, which occur when more than one application contains an applied-for string of characters that are identical or confusingly similar. Contention sets must be resolved prior to the execution of a Registry Agreement. Auctions may be conducted privately or facilitated by ICANN as an “auction of last resort.” In private auctions, the proceeds are generally divided among the applicants that do not prevail; in an ICANN auction the proceeds go to ICANN.

These auctions are carried out using an ascending- clock procedure. In these multi-round auctions, the auctioneer sets a start and end price for each round, and parties that match the end price enter the next round. The process continues until enough applications have exited the auction so that those that remain are no longer in contention. The prevailing applicant pays the final price and may proceed toward delegation as a gTLD.

Backend Registry Operator:

The entity responsible for maintaining the registry database for a TLD and carrying out other technical requirements, sometimes referred to as a registry services provider. The backend operator may be the Registry Operator or another entity performing these responsibilities as a subcontractor.


The defensive practice of preventing a domain name from being made available for registration, for a fee. In contrast to registered domains, blocked domains are not associated with a website. Blocks may also be available for multiple TLDs operated by a single applicant.

BRG (Brand Registry Group):

A working group outside of ICANN’s policy-making structure that represents the interests of .brand registry applicants and registry operators in the new gTLD program.

Cash Escrow:

See COI (Continued Operations Instrument)

ccTLD (Country Code Top Level Domain):

These two-letter top-level domains are assignable to countries and territories, such as .uk (United Kingdom), .de (Germany) and .jp (Japan). See the IANA database for an up- to-date listing of all TLDs, including ccTLDs.

Claims Period:

A period during which trademark owners and prospective registrants receive a notice if a domain name is registered that is an identical match to a mark recorded in the Trademark Clearinghouse (TMCH). The Claims Period is one of the mandatory Rights Protection Mechanisms for the 2012 gTLD round. The Claims Period runs during all Limited Registration Periods and for the first 90 days of General Availability. The notifications provided during the claims period are as follows:

  1. If a potential registrant tries to register a domain name that exactly matches a trademark in the TMCH, the Registrar must provide a Claims Notice to the potential registrant. The Claims Notice provides information about the trademark(s) and trademark holder(s), and requires the potential registrant to provide an acknowledgement to proceed. Registration can continue once confirmation is received.
  2. If a domain name that is an exact match to a trademark in the TMCH is successfully registered, a notification e-mail must be sent to the trademark holder(s) that the registration has been made. These notifications are sent directly by the Trademark Clearinghouse.

Closed Registry:

In a closed or exclusive access registry registrations are only permitted by the Registry Operator and its affiliates or trademark licensees. Specification 13 prohibits the operation of a “generic string” TLD as an exclusive access registry.

COI (Continued Operations Instrument):

A financial instrument required of all new gTLD applicants in the form of a letter of credit (LOC) or a cash escrow account that ICANN can draw on to maintain the technical functions of the registry in case it fails.

Community TLD:

A Top Level Domain operated for the benefit of a clearly defined community. An applicant for a community-based TLD must be prepared to substantiate their status as representative of the community named in the application. Community TLDs also require registration restrictions that limit registrations in the TLD to members of that community.

CPE (Community Priority Evaluation):

A process established by ICANN to resolve a string contention if one or more members of a Contention Set is a Community Applicant. If the applicant is successful in its CPE, then it gains priority rights to the string over non-Community applications in the Contention Set. Community Priority Evaluation consists of an independent panel evaluation across four criteria: Community Establishment; Nexus between Proposed String and Community; Registration Policies, and Community Endorsement.


Any group of people and/or businesses that share a common perspective or interest in the domain name space. Constituencies are a formal element of ICANN’s structure and can vote on policies. For example, the Commercial Stakeholder Group is further divided into the Business Constituency, the Intellectual Property Constituency, and the Internet Service Provider Constituency.

Consensus Policy:

A policy created through the Policy Development Process of the GNSO (Generic Names Supporting Organization), as specified in Annex A of the ICANN Bylaws. Once adopted, Consensus Policies become binding for all registries and/or registrars (as applicable).

Contention Set:

A group formed when multiple TLD applicants applied for an identical string. A limited number of Contention Sets exist for strings that are similar but non-identical, as a result of the String Similarity Review or String Confusion Objections.

CQs (Clarifying Questions):

Questions that are asked of a gTLD applicant during evaluation of their application, when evaluators feel they do not have enough information to award a passing score to the application. During the 2012 gTLD round, applicants were given four weeks to respond, and the supplementary documentation or information provided then became part of their Initial Evaluation.


The introduction by ICANN and IANA of a new TLD in the DNS root. At delegation, the root zone, which is managed by IANA, is edited to include the new TLD, and the management of domain name registrations is turned over to the registry operator. The delegation details are included in the Root Zone Database.

DNS (Domain Name System):

The Domain Name System translates user-friendly, unique alphanumeric addresses or domain names, such as “neustar.biz,” into machine-readable, numerical Internet protocol (IP) addresses, such as “”. This protocol identifies every computer on the Internet.

DNSSEC (DNS Security Extensions):

DNS security extensions provide origin authentication and integrity checks of DNS data, to address the problem of DNS cache poisoning. It’s most effective if a particular TLD zone, including its registries, is DNS protected.

Data Escrow:

The practice of storing data with a third party, required of all registrars and gTLD registries by ICANN, to safeguard registrants in case of registry or registrar failure, accreditation termination, or accreditation relapse without renewal.

DRP (Dispute Resolution Provider):

An independent party used by ICANN to resolve domain related disputes. Dispute Resolution Providers are used to resolve Uniform Rapid Suspension (URS) and Uniform Domain Name Dispute Resolution Policy (UDRP) complaints. Registry Operators may also independently appoint Dispute Resolution Procedures to carry out processes such a Sunrise Disputes.

Equal Access:

The requirement that registries subject to the code of conduct treat registrars equally, by executing Registry- Registrar Agreements on the same terms and providing notice of promotions and other updates at the same time.

Extensible Provisioning Protocol (EPP):

Protocol used for electronic communication between a registrar and a registry for provisioning domain names.


Founders’ Program:

A promotional program offered by some Registry Operators in the launch process of a TLD that allows parties who agree to promote actively and market their new domain name (and by extension the new TLD), to use that domain before the general public. This program that is also called a Pioneer Program would be the very first opportunity for anyone to obtain rights to a domain name using that TLD. Highly motivated users and investors could avail themselves of this opportunity to get the most coveted names.

GAC (Governmental Advisory Committee):

The ICANN committee that represents national governments and handles providing public policy advice, particularly in areas related to national and international laws and agreements. The advice may be provided by individual GAC members or by “consensus.” There is a strong precedent for the ICANN Board to accept and implement GAC Consensus Advice.

GAC Early Warning:

A notice issued by the GAC concerning a gTLD application that is seen as potentially sensitive or problematic by one or more governments.

General Availability:

The period when domain names are offered without restriction on a first come, first served basis, according to the standard eligibility requirements for the registry.

GDD (Generic Domains Division):

The department of ICANN which is responsible for New gTLDs.

GDD Portal (Generic Domains Division Portal):

A centralized system at icann.secure.force.com/gdd that allows applicants to submit contact, registry onboarding and TLD startup information required for launching a TLD, and serves as the ongoing system for communication between registry operators and ICANN. Applicants gain access after executing the Registry Agreement with ICANN.

GNSO (Generic Names Supporting Organization):

ICANN’s policy development and advisory body for generic TLDs is made up of four stakeholder groups: Commercial, Non-Commercial, Registries and Registrars. Policy development is conducted by GNSO Working Groups and overseen by the GNSO Council, which includes representatives from these four groups.

Go Live:

A colloquial term for the launch of a TLD. When a new gTLD goes live, people and businesses can apply for or register domains within it.

gTLD (Generic Top Level Domain):

This category includes most TLDs with three or more characters, both unsponsored and sponsored. All gTLDs are subject to Consensus Policies developed through ICANN’s Generic Names Supporting Organization. See the IANA database for an up-to-date listing of all TLDs, including gTLDs.


The practice of awarding a domain name to a registrant based on the pre-existence of another domain name, usually under a different TLD.

IRP (Independent Review Process):

A third party process to review complaints from a person or entity that believes the ICANN Board has acted inconsistently with its Articles of Incorporation or Bylaws. Under current rules, the determinations of the IRP are not binding.

IANA (Internet Assigned Numbers Authority):

The department of ICANN responsible for overseeing IP address allocation; coordinating the assignment of protocol parameters; managing DNS, including delegating top-level domains; and overseeing the root name server system. IANA performs the technical delegation of TLDs and address space and manages protocol parameter assignments.

ICANN (Internet Corporation for Assigned Names and Numbers):

The internationally organized non-profit corporation that manages DNS to ensure the operational stability of the Internet. ICANN handles Internet Protocol (IP) address space allocation, protocol identifier assignment, and root zone management. It also coordinates the development of policies for the Domain Name System through bottom-up, consensus-based processes involving various stakeholders.

IDN (Internationalized Domain Name):

Any domain name that includes characters that are not ASCII characters. An IDN can contain Latin letters with diacritical marks as well as characters from non-Latin scripts, such as Arabic or Chinese. An IDN name permits the global community to use a domain name in their native language or script and is enabled by allowing domain names to have characters from different scripts.

IDNA (Internationalizing Domain Names in Applications):

The technical protocol used for processing domain names containing non-ASCII characters in the DNS.

IE (Initial Evaluation):

The first phase of evaluating a new gTLD application. It includes string reviews, to determine that the applied-for gTLD string is not expected to cause security or stability problems; and applicant reviews to assess whether the applicant has the necessary technical, operational and financial capabilities to operate a registry.

IETF (Internet Engineering Task Force):

A large, open international community of network designers, operators, vendors and researchers concerned with the evolution of Internet architecture, and the smooth operation of the Internet. The IETF handles the development of protocol parameters, which define standards for Internet operations.

IP Claims (Intellectual Property Claims):

See Claims Period

IPC (Intellectual Property Constituency):

The GNSO constituency that represents the interests of intellectual property owners worldwide. The IPC is particularly focused on trademark and copyright concerns and is part of the Commercial Stakeholder Group.


The period immediately following the launch of a TLD when the general public can apply to register a domain name. In recent years, the term has shifted to refer to an interim period between Sunrise and Open Registration where registrants can make submissions for an increased fee.

Launch Phases:

The Sunrise Period is a limited pre- registration period and is the mandatory first phase of all new gTLDs. The Sunrise is the right period to register brand names as domains. All registries are required to have a Sunrise Period open only to holders of a validated trademark record in the Trademark Clearinghouse (TMCH)

Registries have the option of including a Landrush period in their launch timeline, though this phase is not mandatory. Landrush is the right time to register very important names, which are not or cannot be trademarked.

This is the open-ended phase where the TLD is available on a “first-come, first- served” basis to the general public. During the first ninety (90) calendar days after General Availability opens for each new gTLD, registries must provide Trademark Claims. The Claims Period cannot overlap with the Sunrise phase.

The “Quiet Period” is simply a short lull between the Sunrise and Landrush phases, or between Landrush and General Availability. During the Quiet Period, no domains are able to be registered.

Legacy TLDs:

gTLDs that were delegated prior to the 2012 New gTLD Application Round.

LRP (Limited Registration Period):

A period prior to general registration during which a registry operator restricts registrations, generally to a defined pool of applicants other than sunrise-eligible rights holders.

Name Collision:

A concern raised during the 2012 New gTLD Application Round that new TLDs would overlap with strings used to name internal networks, which could give rise to leakage between such systems and the Internet if the networks were improperly configured. As a result of these issues, all registries are required to undertake a 90-day mitigation period from the date of delegation during which no second level domains other than NIC.TLD may be created.

NTAG (New gTLD Applicant Group):

The interest group representing new gTLD applicants within ICANN. It has observer status in the Registry Stakeholder Group and is open to all new gTLD applicants. The NTAG will eventually be sunset as its members execute their Registry Agreements and become eligible for full membership in the RySG.


During the application process, third parties can challenge a new gTLD application on one of four grounds:

  • String Confusion (the string is confusingly similar to another TLD string, either existing or applied-for);
  • Legal Rights (the string violates the legal rights of the objector, e.g., trademark infringement);
  • Community Objection (the community that a string targets believes the application would be detrimental);
  • Limited Public Interest (a string contradicts norms of morality and public order as defined under international law).

PDDRP (Post-Delegation Dispute Resolution Procedure):

PDDRP provides trademark holders with a process to seek redress from new gTLD registry operators that exhibit bad faith intent to profit from the systemic registration of infringing domain names. Remedies can include termination.

PDT (Pre-Delegation Testing):

A technical testing phase prior to delegation during which new gTLD applicants must demonstrate that the registry is ready for operation, and which must be passed before a registry can be introduced into the root zone.

Premium Domain Names:

Domain names that are held back during launches by the Registry Operator in order to be sold at a higher price than “standard” domain names or allocated for special purposes, often through an auction or Request for Proposal (RFP) process. Premium names also refer to names that have already been registered, but not available to be sold at the normal registration price due to their higher perceived value. Domain and market influences set the ‘premium’ price of such domain names.

PIC (Public Interest Commitment):

Additional commitments included in the ICANN Registry Agreement, through the addition of Specification 11, to address GAC advice on new gTLDs. Commitments included in this PIC Specification include:

  • Using only registrars accredited under the 2012 Registrar Accreditation Agreement; • Including language in registration agreements barring abusive and illegal behaviors; • Conducting security monitoring and maintaining records of identified threats;
  • Publishing clear, non-discriminatory registration criteria; and
  • Not operating a “generic string” as a closed registry.

Promotional Names:

Any of the up to 100 domains that are necessary for the “operation or the promotion of the TLD.” They can be self-allocated to the registry without having to use a registrar, and used before the Sunrise Period. All other names must be registered through an ICANN-accredited registrar and cannot be allocated before the conclusion of the Sunrise Period.

Public Interest Commitment Dispute Resolution Procedure (PICDRP):

A dispute resolution procedure available to any third party that believes it has been harmed by a Registry Operator’s failure to adhere to its Public Interest Commitments.

Reconsideration Request:

A process that can be entered into if an entity believes that it was materially affected by an action or inaction by ICANN staff that contravened established policies and procedures, or which failed to consider material information.


An individual who registers a domain name through a registrar. Registrants enter a contract that sets forth the terms under which the registration is accepted and will be maintained.


An entity that has entered into a Registrar Accreditation Agreement with ICANN to accept and maintain registrations for domain names. The registrar collects and retains records containing technical and contact information provided by registrants, which are then submitted to a central directory known as the registry. The registrar can make changes to a registry by adding, deleting, or updating domain name records. There are many different registries competing to sell domains. Unless exempt from the Code of Conduct, registries are required to execute a Registry-Registrar Agreement with all interested registrars on the same terms. See the ICANN Directory for an up-to-date listing of all accredited registrars.

Registrar Tool Kit:

The Registrar Tool Kit is a software development kit that will support the development of a registrar software system for registering Internet domain names in the registry using the EPP registry- registrar protocol. The registrar uses this toolkit to develop automated scripts enabling changes to a registry for the purposes of adding, deleting, or updating domain name records.


The authoritative master database of domain names recorded within a top level domain. A registry operator maintains this master database, and generates the zone files that direct Internet traffic to and from top level domains, either independently or through a contract with a Backend Registry Operator.

Registry Agreement:

The agreement executed between ICANN and a successful gTLD applicant upon completion of Initial Evaluation and resolution of a Contention Set (if applicable).

Registry Operator:

An entity that enters into a Registry Agreement with ICANN and is responsible for setting up and maintaining the operation of the registry either independently or through a contract with a Backend Registry Operator. The Registry Operator also sets the policies for the TLD(s) that it operates.

Restricted Registry:

A TLD with that has implemented registration restrictions limiting who can register in the TLD.

Registry-Registrar Agreement (RRA):

The agreement dictating the terms of the relationship between the registry operator and its registrars including legal terms, registration requirements, registry fees, and more. The registry sets the terms of the RRA. Registries are required to offer non-discriminatory access to all registrars by allowing all registrars to execute an identical RRA. Requirements in the RRA should pass through the registrar to each of its resellers.

Registry Service Provider:

See Backend Registry Operator


An entity selling TLD registrations on behalf of a registrar that is not independently accredited to sell domain names in that TLD. The registrar remains responsible for all RRA requirements for the registrations that it sponsors, whether it has sold them directly or through a reseller.

Reserved Name:

All registry operators are required by their Registry Agreement to exclude certain domain names from registration in a Top Level Domain (TLD). These reserved names include strings that are for Country Code Top Level Domains (ccTLDs), ICANN-related names (such as ICANN), IANA-related names (such as example), and names that the registry operator can use in connection with the operation of the TLD.

RGP (Redemption Grace Period):

A 30-day period following the deletion of a domain name from a registry, intended to allow for the reversal of inadvertent or fraudulent domain name deletions. During this period, the registrant, registry, and/or registrar can identify and amend any mistaken deletions. During the RGP a domain name may be redeemed (or renewed) by the original registrant for an additional fee. Afterwards, there is an additional five-day period before a domain is finally deleted in order to notify all registrars of the deletion.


The root is the authoritative file that identifies each of the top-level domains and its authoritative name servers. ICANN manages the root on which the great majority of Internet traffic flows. ICANN manages its root centrally, but service of the root zone file is provided by a series of geographically and operationally diverse root servers.

Root Nameserver:

A DNS server that answers requests for the DNS root zone, and redirects requests for a particular TLD to that TLD’s nameservers. The term is generally used to describe the thirteen primary root nameservers that implement the root namespace domain for the Internet’s official global implementation of the Domain Name System.

Root Zone:

The root zone database represents the delegation details of top-level domains, including gTLDs and ccTLDs. It is managed by IANA, which is responsible for coordinating delegations.

RSEP (Registry Service Evaluation Process):

The process by which registries can make changes to their Registry Agreements or introduce new registry services. RSEPs are submitted through the Registry Request System (RRS); RRS credentials must be requested through the ICANN GDD Portal.

RYSG (Registries Stakeholder Group):

The GNSO Stakeholder Group representing registry operators. Any entity that has executed a Registry Agreement with ICANN is eligible for membership in the RySG. The RySG engages in information sharing and collective advocacy on ICANN issues affecting registries.

Sponsored TLDs (for example, .aero, .coop, .edu, .jobs, and .museum) were applied for during the 2004 round and have a sponsoring entity that represents the community served by the TLD and that sets many of the policies.

Sponsoring Organization or “Sponsor”:

An organization with defined policymaking authority for a sponsored TLD. The sponsor develops policies so that the TLD operates for the benefit of the sponsored TLD community, which includes entitles most directly interested in it. The sponsor is obligated to exercise its delegated authority according to fairness standards, and in a manner representative of the sponsored TLD community.

SRS (Shared Registration System):

The software provided by a registry to facilitate its management with the intention of an unlimited number of registrars being able to compete in the domain name registration business by using one shared registry. It is used by registrars to connect to the registry to register domain names and update nameservers or contact information.

Specification 13:

An additional specification included in the Registry Agreement for .brand applicants that:

  • Provides an automatic Code of Conduct exemption;
  • Waives the requirement to provide non-discriminatory access to all ICANN registrars, allowing instead for the registry to designate up to three “preferred registrars” to serve the TLD; and
  • Provides a limited 2-year “cooling off” period prior to re-delegation of the TLD to a successor registry operator.

This provision is included in Registry Agreements for .brand registries that complete a qualification process showing that the TLD would be closed; that it corresponds exactly to a registered trademark of the Registry Operator, and that application of the Code of Conduct would not be necessary to protect the public interest.

SG (Stakeholder Group):

The SGs are the basic building blocks of ICANN’s GNSO. The GNSO is divided into four stakeholder groups: the Registries Stakeholder Group (RySG) and Registrar Stakeholder Group (RrSG), which fall within the Contracted Party House; and the Commercial Stakeholder Group (CSG) and Non-Commercial Stakeholder Group (NCSG).

String Contention:

See Contention Set


The launch phase that allows mark holders to register domain names in a TLD before registration is generally available. All new gTLD registries have an obligation to provide a minimum of 30 days notification of Sunrise followed by a 30-day Sunrise period, or to provide a Sunrise of no less than 60 days. To participate in the Sunrise a registrant must have an exact- match trademark to the second level domain in question registered in the Trademark Clearinghouse (TMCH), though the Registry Operator may set additional registration criteria. The Registry Operator also determines the allocation method for multiple submissions requesting the same domain name (e.g., first-come, first-served; an auction; or another method).

Thick Registry:

A registry model in which all information associated with registered entities, including both technical and social information, is stored in the registry repository.

Thin Registry:

A registry model in which only operational data about each domain is stored in the central registry database, while contact and billing information is maintained by the registrar sponsoring the domain name.

Top Level Domain (TLD):

The names at the top of the DNS naming hierarchy, appearing in Internet addresses as the string of letters following the rightmost “dot”, such as “biz” in “www.neustar.biz”.

TMCH (Trademark Clearinghouse):

A central global repository of trademark rights information to protect trademarks in the new gTLD program. It eliminates the need for brand owners to submit their trademark information to separate databases belonging to each registry. The TMCH maintains and distributes to registries the database of Sunrise-eligible labels and provides the mark holder-facing notices of exact-match registrations of their trademarks.

Trademark Claims:

See IP Claims.

UDRP (Uniform Domain Name Dispute Resolution Policy):

A policy for resolving disputes arising from alleged abusive registrations of domain names. It allows for expedited administrative proceedings initiated by a trademark rights holder. A trademark owner that prevails in a UDRP may have the domain name transferred. All gTLDs are required to comply with the UDRP.

URS (Uniform Rapid Suspension):

A rapid and efficient mechanism for trademark holders to “take down” undeniably infringing domain names. A successful proceeding results in suspension of the domain name, rather than transfer, with mandatory compliance by all gTLD operators. It provides a faster and less expensive alternative to UDRP, but only for clear-cut infringements.

UA (Universal Acceptance):

Acceptance of all top-level domains, including IDNs, into Internet systems, applications, fields, and more. UA includes resolution of domain names in all browsers, the ability to send email to and from emails on all new TLDs, and the ability of other systems to recognize new gTLDs as valid, both in internal and external-facing validations. UA can sometimes also refer to “Universal Awareness,” or public awareness of and comfort with new TLDs.


The source for public access to data associated with registered domain names, including the registrant and the administrative, billing and technical contact information provided by registrars for domain name registrations. Registrars are required to remind registrants to update, review and correct their WHOIS data at least once a year.

Zone file:

A text file on a nameserver that designates a domain name with all its associated subdomains, IP addresses, and mail server. It is used for resolving specified Internet domain names to the appropriate number form of an Internet Protocol address (an IP address). A zone file is also called a “DNS table.”

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