DNS & Infrastructure

DNS resolution, record types, nameservers, and the protocols that power domain name lookups.

DNS (Système de Noms de Domaine)

Hierarchical naming system that translates domain names into IP addresses.

Serveur de Noms (Nameserver)

Server that stores DNS records and responds to DNS queries for a domain zone.

Enregistrement A

DNS record mapping a domain name to an IPv4 address.

Enregistrement AAAA

DNS record mapping a domain name to an IPv6 address.

Enregistrement CNAME

DNS record that creates an alias from one domain name to another canonical name.

Enregistrement MX

DNS record specifying the mail server responsible for receiving email for a domain.

Enregistrement TXT

DNS record holding arbitrary text data, commonly used for email authentication and domain verification.

Enregistrement NS

DNS record that delegates a DNS zone to an authoritative nameserver.

Résolveur DNS (DNS Resolver)

Software or service that performs recursive DNS lookups on behalf of clients.

Cache DNS (TTL)

Temporary storage of DNS query results with a Time-To-Live expiration.

Serveur DNS Faisant Autorité

Server that holds the original DNS records for a zone and provides definitive answers.

Fichier de Zone DNS

Text file describing a DNS zone with records for all domains in that zone.

Enregistrement SOA

Start of Authority record containing administrative information about a DNS zone.

Sous-domaine

Domain that is part of a larger domain, created by prepending a label (e.g., blog.example.com).

Adresse IP

Numerical label (IPv4 or IPv6) assigned to each device connected to a computer network.

Résolveur DNS Récursif

Server that performs the full DNS resolution chain on behalf of clients and caches results.

Serveur Racine DNS

Top-level nameservers that direct resolvers to the correct TLD nameservers.

Zone DNS

Administrative partition of the DNS namespace managed by a single authoritative authority.

Enregistrement PTR (DNS Inverse)

DNS record that maps an IP address back to a hostname for reverse DNS lookups.

Délégation DNS

Transfer of DNS authority for a child zone to designated nameservers via NS records.

DNS Round Robin

Load-balancing technique using multiple IP addresses on a single hostname to distribute traffic.

DNS Sinkhole

DNS configuration that redirects malicious domains to a controlled IP to block or analyze threats.

EDNS (Mécanismes d'Extension pour DNS)

RFC 6891 extension to the DNS protocol enabling larger messages, DNSSEC, and new option codes.

Attaque par Amplification DNS

DDoS technique exploiting open DNS resolvers to flood a victim with amplified response traffic.

Cache Négatif (NXDOMAIN)

Caching of NXDOMAIN and NODATA DNS responses to prevent repeated queries for non-existent names.