DNS Service Discovery (DNS-SD)
A naming convention and query method for discovering service instances and their parameters using PTR, SRV, and TXT records. It is often paired with multicast DNS on local networks.
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Browse the glossaryDNS glossary — page 4
311 definitions associated with DNS.
Browse DNS definitions
311 matching terms
Page 4 of 13DNS shadowing
The malicious creation of many subdomains beneath a legitimately registered domain, often after account compromise, to host phishing, malware, or command-and-control infrastructure. The parent domain can initially appear reputable.
Read definitionDNS sinkhole
A controlled DNS response that directs prohibited or suspicious names to an analysis, notification, or non-routable destination. Sinkholes can disrupt malware while generating telemetry about affected clients.
Read definitionDNS spoofing
The delivery of a forged DNS response intended to be accepted as legitimate. It can target a stub, recursive resolver, application, or network path.
Read definitionDNS tunneling
The encoding of data or command traffic inside DNS labels, record data, or query patterns to bypass normal channels. Detection often examines label length, entropy, query volume, record types, and destination reputation.
Read definitionDNS UPDATE
The standardized DNS operation that adds, deletes, or changes records in a zone. Updates can use prerequisites and are normally authenticated with TSIG, SIG(0), GSS-TSIG, or platform access controls.
Read definitionDNS view
A server-side configuration that provides different DNS data or behavior to different clients, often based on source network, interface, or identity. Views are commonly used for split DNS and overlapping namespaces.
Read definitionDNS water torture
A random-subdomain denial-of-service attack that sends many queries for unique nonexistent names, forcing recursive and authoritative servers to do repeated work while bypassing positive cache reuse.
Read definitionDNS zone
A coherently managed portion of the DNS namespace served as authoritative data. A zone begins at its apex and ends at delegated child-zone cuts.
Read definitionDNS64
A resolver function that synthesizes AAAA records from IPv4 A records using a configured IPv6 prefix, allowing IPv6-only clients to reach IPv4 services through NAT64.
Read definitiondnstap
A structured binary event stream for recording DNS message and resolver processing data. It provides richer and often more efficient telemetry than plain-text query logs.
Read definitionDomain
A node in the DNS namespace together with all names below it. A domain is not necessarily the same as a zone because delegations can divide a domain into separately administered zones.
Read definitionDomain generation algorithm (DGA)
An algorithm used to produce many candidate domain names, often so malware can locate command-and-control infrastructure despite takedowns. DGA domains may show unusual entropy, length, timing, and NXDOMAIN patterns.
Read definitionDomain name
An ordered sequence of DNS labels representing a node in the namespace. In presentation format, labels are separated by dots.
Read definitionDomain shadowing
Abuse in which an attacker compromises control of a legitimate domain and creates unauthorized subdomains for malicious activity. It can evade reputation systems that score only the parent domain.
Read definitionDomain suffix search
The client behavior of appending configured suffixes to a relative name and trying one or more resulting FQDNs. Search behavior varies by operating system and can create information leakage or unexpected lookups.
Read definitionDSO
DNS Stateful Operations, a framework for maintaining stateful sessions and exchanging asynchronous DNS-related messages over a persistent transport. It supports capabilities such as DNS Push Notifications.
Read definitionDSYNC record
A DNS record used to publish the location of a service that synchronizes delegation-related data between child and parent. It supports automated delegation maintenance workflows.
Read definitionDynamic update
An update made through a protocol or automated process rather than by editing static zone data. In most DNS contexts it refers to RFC 2136 DNS UPDATE.
Read definitionE.164
The international public telecommunication numbering plan used for telephone numbers. ENUM can represent an E.164 number as labels beneath e164.arpa for DNS-based service discovery.
Read definitionECS
EDNS Client Subnet, an EDNS option that lets a resolver include part of a client's network prefix in an upstream query so an authoritative service can tailor the answer geographically. It can improve content localization but reduces privacy and cache efficiency.
Read definitionEDE
Extended DNS Error, an EDNS option that adds a more specific reason to a DNS response, such as blocked, stale answer, DNSSEC bogus, or network error. The normal RCODE remains present.
Read definitionEDNS
Extension Mechanisms for DNS, a framework that expands DNS message capabilities without changing the original fixed header. An OPT pseudo-record carries a larger UDP size, the extended RCODE, version, flags, and options.
Read definitionEDNS buffer size
The UDP payload size a requester advertises in the OPT record. Oversized values can cause fragmentation or path failures, while undersized values cause more truncation and TCP or QUIC fallback.
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