DNS

Content Delivery Network (CDN)

A Content Delivery Network (CDN) is a geographically distributed network of servers that caches and delivers web content — such as images, scripts, and static…

DNS (Domain Name System)

The Domain Name System (DNS) is the internet's hierarchical naming system that translates human-readable domain names, like example.com, into the numeric IP ad…

SSL/TLS Certificate

An SSL/TLS certificate is a digital file that cryptographically verifies a website's identity and enables encrypted HTTPS connections between a server and its…

Nameserver

A nameserver is a server that translates a domain name into the DNS records needed to route traffic, such as the IP address a browser should connect to or wher…

DNS Fundamentals on Windows Server

Learn how the Windows Server DNS role resolves names to IP addresses and why DNS is the backbone that Active Directory depends on.

DNS Zones and Records

Understand how Windows Server DNS organizes namespace data into zones and the record types administrators configure most often.

Integrating DNS with Active Directory

Understand how Active Directory depends on DNS for service discovery, dynamic updates, and site-aware logon, and how to configure that integration correctly.

Cloud DNS Basics

Understand how Google Cloud DNS serves authoritative public and private zones from a global anycast network, the core record types you'll configure, and how DN…

Azure DNS Basics

Learn how Azure DNS hosts and resolves domain records, the standard record types, and how Alias records solve Azure-specific limitations like apex domain routi…

DNS: The Domain Name System

How DNS translates human-friendly domain names into IP addresses through a distributed hierarchy of resolvers and servers.

DNS and Cloud Networking

Understand how cloud DNS services resolve domain names and support advanced routing policies like latency-based and geolocation routing.

DNS and CDNs

How the Domain Name System resolves human-readable names to IP addresses, and how Content Delivery Networks cache and serve content from edge locations close t…

How Does DNS Work?

DNS (Domain Name System) is the internet’s phonebook: it translates human-readable domain names like example.com into the IP addresses machines use to connect,…

What is DHCP (Dynamic Host Configuration Protocol)?

DHCP (Dynamic Host Configuration Protocol) is a network protocol that automatically assigns IP addresses and other configuration details — like subnet mask, de…

What is the HTTP Request Lifecycle?

The HTTP request lifecycle is the full sequence a browser follows to load a resource: DNS resolution, TCP (and TLS) connection setup, sending the HTTP request,…

What is the Application Layer (OSI Layer 7)?

The Application Layer (Layer 7, the topmost OSI layer) is where network-aware software directly interacts with the user or another program, providing the proto…

What is SMTP (Simple Mail Transfer Protocol)?

SMTP (Simple Mail Transfer Protocol) is the application-layer protocol used to send and relay email between mail servers, and from a mail client to its outgoin…

What are the Common DNS Record Types?

DNS records are typed entries stored in a zone file that map a domain name to different kinds of information — most commonly an A record for an IPv4 address, A…

How Does DNS Caching Work?

DNS caching stores the result of a domain name lookup at multiple layers — the browser, the operating system resolver, and recursive resolvers along the way —…

Recursive vs Iterative DNS Queries: What is the Difference?

A recursive DNS query asks a resolver to fully resolve a name and return the final answer, taking on the work of contacting other servers itself, while an iter…

What is DNS over HTTPS (DoH)?

DNS over HTTPS (DoH) is a protocol that carries standard DNS queries and responses inside encrypted HTTPS connections instead of sending them as plaintext UDP…

What is Reverse DNS?

Reverse DNS (rDNS) is the lookup that maps an IP address back to a hostname, the opposite direction of a normal DNS query, and it works by querying a special P…

DNS Load Balancing Explained

DNS load balancing spreads traffic across multiple servers by having the DNS server return different IP addresses for the same hostname to different clients or…

What is nslookup?

nslookup is a command-line tool that queries DNS servers to resolve a domain name to its IP address, or an IP address back to a domain name, and can also fetch…

What is Anycast Routing?

Anycast is a routing method where the same IP address is announced from multiple physically distinct servers, and the network automatically routes each client…

What Are Common UDP Use Cases?

UDP is best used where low latency and minimal overhead matter more than guaranteed delivery, such as DNS lookups, live video/voice streaming, online multiplay…

When Should You Use TCP vs UDP?

Use TCP when correctness and ordered, complete delivery matter more than latency (web pages, file transfers, APIs), and use UDP when low latency and minimal ov…

What is Dual Stack Networking?

Dual stack networking means a device, router, or network runs both the IPv4 and IPv6 protocol stacks at the same time, each with its own independent address, s…

What is a DNS Zone?

A DNS zone is a distinct, administratively delegated portion of the DNS namespace whose records a specific set of name servers is authoritative for, defined by…

What is a DNS Resolver?

A DNS resolver (or recursive resolver) is the DNS server component that takes a client’s hostname lookup request and does the work of walking the DNS hierarchy…

Authoritative vs Recursive DNS Server: What is the Difference?

A recursive DNS server is the resolver a client talks to that does the legwork of tracking down an answer by querying other servers on the client’s behalf, whi…

What is DNSSEC?

DNSSEC (Domain Name System Security Extensions) is a set of extensions to DNS that adds cryptographic signatures to DNS records so a resolver can verify a resp…

What is DNS Cache Poisoning?

DNS cache poisoning (also called DNS spoofing) is an attack where an attacker injects a forged DNS response into a resolver’s cache, tricking it into associati…

What is Anycast DNS?

Anycast DNS is a routing technique where the same IP address is announced from multiple physically distributed DNS servers, and the internet’s routing infrastr…

What is Geo Load Balancing?

Geo load balancing routes each client request to the nearest or best-performing data center or region based on the client’s geographic location, typically usin…

What is DNS Spoofing?

DNS spoofing (also called DNS cache poisoning) is an attack that injects a forged DNS response into a resolver or client, causing a legitimate domain name to r…