Domain-related Terminology and Concepts
Top-Level Domain (TLD): The rightmost part of a domain name, such as .com, .cn, which determines the category and regional attributes of the domain.
Second-Level Domain: The core identifier immediately to the left of the top-level domain, such as "racent" in racent.com, which is the main entity actually registered by the user.
Subdomain: The extended part to the left of the second-level domain, such as "www" in www.racent.com, which can be created for free without quantity limits.
FQDN (Fully Qualified Domain Name): A complete domain name that includes all hierarchy levels, such as mail.racent.com., which ends with a dot for precise resolution.
IP Address: A numeric label for internet-connected devices, such as 192.168.1.1; domain names are converted to IP addresses via DNS resolution to enable access.
Domain Resolution: The process by which the DNS system converts domain names into IP addresses, allowing browsers to access website servers.
DNS (Domain Name System): A distributed database system for the internet that implements the mapping relationship between domain names and IP addresses.
Whois Lookup: A global database for querying domain registration information, where key details such as the registrant, expiration time, and DNS servers can be obtained.
Domain Transfer Code (EPP Key): A 6-16 character secure authorization code used for domain registrar transfer operations.
A Record: The most basic type of DNS record, which points a domain name to an IPv4 address, such as @ A 192.0.2.1.
AAAA Record: A DNS record that points a domain name to an IPv6 address, such as www AAAA 2001:db8::1.
CNAME record: Creates a domain alias that points to the primary domain, for example blog CNAME racent.com.
MX record: Specifies the address of the mail server, for example @ MX 10 mail.racent.com.
TXT record: Stores text verification information, commonly used for email security authentication such as SPF and DKIM.
TTL (Time To Live): The effective duration (in seconds) for which a DNS record remains in cache, which affects the speed of resolution changes.
Domain registrar: An ICANN-accredited domain service provider (such as Racent) that offers registration, renewal, management and other related services.
Domain registry: The official organization that manages the top-level domain database.
Domain status code: A code indicating the management status of a domain, such as clientHold (registrar lock) and serverHold (registry lock).
DNSSEC: Domain Name System Security Extensions, which prevents DNS spoofing attacks through digital signatures.
Domain privacy protection: Hides the registrant's contact information in public Whois data to prevent information leakage.
Domain lifecycle: The complete process from registration to deletion: Available → Registered → Active → Expired → Grace period (30 days) → Redemption period (30 days) → Deleted.
Domain parking: Displaying advertising pages on unused domains to generate revenue.
301 redirect: A permanent domain redirect that passes SEO authority to the new address.
302 redirect: A temporary domain redirect that does not pass SEO authority.
Domain brokerage: A third-party service that professionally facilitates transactions of high-value domains.
UDRP (Uniform Domain-Name Dispute-Resolution Policy): Domain dispute arbitration rules established by ICANN.
IDN (Internationalized Domain Name): A domain name that supports non-English characters, such as 中文.网址, which is actually stored in Punycode format.
CDN (Content Delivery Network): Accelerates website access through global nodes, and is usually connected via CNAME records.
Web3 domain: A blockchain-based domain name system, such as myname.eth, which can be held permanently without renewal.
DNS over HTTPS (DoH): Encrypts DNS query traffic through the HTTPS protocol to improve privacy.
Domain portfolio: A collection of domain assets held by an investor, usually including domains with high-value keywords.
Registrar Lock (Domain Lock): A security feature that prevents unauthorized domain transfers.
Domain renewal grace period: A buffer period of 30 days after expiration during which the domain can be renewed at the original price.
Domain redemption period: The phase after the grace period during which a domain can be redeemed at a high fee (usually $100+).
SSL certificate: A digital certificate that deploys HTTPS encryption for a domain and verifies the identity of the website.
HTTP Strict Transport Security (HSTS): A response header protocol that forces browsers to connect over HTTPS.
Authoritative DNS server: A dedicated server that stores domain resolution records, such as ns1.racent.com.
Recursive DNS server: A DNS query relay server provided by ISPs, such as 8.8.8.8 (Google DNS).
Domain traffic analytics: A service that collects statistics on data such as domain visit volume and traffic sources.
Domain valuation: Assesses the market value of a domain based on factors such as keywords, length, and suffix.
Domain auction: A mode of trading domains through a bidding platform.
Domain backorder: A service that automatically registers a domain the moment it is deleted.
Domain template: A pre-saved set of registration information used for fast bulk domain registration.
DNS propagation: The time process during which DNS servers worldwide update records, usually taking 24–48 hours.
Secondary domain market: A trading platform for already registered domains.
Domain arbitration: Resolving domain disputes through legal procedures, such as WIPO arbitration.
Domain monitoring: An alert service that tracks changes in domain status (such as expiration and transfer).
Domain API: A programmatic interface for managing domains programmatically, supporting bulk operations.
Domain blacklist: A list of domains blocked by security agencies due to abuse.
Domain whitelist: A list of trusted domains that are exempt from inspection, commonly used in email systems.
Domain Authority: A trust score (0–100) assigned to a domain by search engines.
Naked Domain: A primary domain without the www prefix, such as racent.com.
Wildcard DNS: *.racent.com points all subdomains to the same IP address.
Domain health check: An automated service that monitors risks such as resolution anomalies and expiration time.