DNS Terminology
In this industry, providers will use different words to say the same thing. We want to make sure that we are all speaking the same lingo, so take a second to look over our terminology before you dive into our knowledge base.
Mapping and Pointing DNS Records
When you create a record, what you’re really doing is telling users that when querying your domain, they should be sent (mapped or pointed) to another location.
Example:
If you want anyone who queries your domain to be sent to your web server (where your website is hosted), you would create an A record that points yourdomain.com to the IP address of your web server.
Endpoint / System
Records can point to IP addresses, hostnames, FQDN’s, servers, CDN’s, other providers, etc. To keep things simple, we’ll often group all of these together under the moniker “endpoint” or “target system”. These words are basically placeholders for whatever we are pointing a record to.
Example:
If we have a record that points our domain to the IP address of our web server, then we will refer to both the IP address and the web server as the endpoint or target system.
FQDN
A Fully Qualified Domain Name is the most unambiguous and exact location in the tree hierarchy of the Domain Name System and most commonly contains: a hostname, domain name, and TLD of a domain in that order.
Example:
<hostname> . <domain> . <tld>
Querying Client
This is how we refer to the person or system that is requesting the record information for a domain.
Example:
If you type a domain into your browser, you are the querying client because you are requesting the record information for that domain.
IP Address
Computers are only able to communicate using numbers and name themselves using IP addresses, which are 4-32 digit integers. There are two types of IP addresses: IPv4 and IPv6.
Example:
The IP address for your localhost is always 127.0.0.1.
Hostname
A hostname is the FQDN of a system. They are usually used when you want to point to a system that has a dynamic (changing) IP address.
Example:
If you want to create a record that points to a CDN, which will return a different IP address depending on the location of the querying client, you would need to point that record to the hostname of the CDN. The CDN will calculate the closest server to the client and return the appropriate IP address.
Root Domain
The root of a domain is also referred to as the apex of a domain. A record that points from the root of a domain is called a “naked” domain because there is not hostname or subdomain preceding it.
Example: The root of www.constellix.com is constellix.com.
Anycast DNS
Anycast is a type of network that uses the “one to many” technique to propagate information. In the context of DNS, Constellix uses an Anycast network to store DNS record information in many different locations.
When someone queries a domain on the Constellix network, they are automatically routed to the closest location where the record information is stored.
Propagation
Whenever you create or update a record, that information is propagated or pushed to all the nameservers in our network. Propagation times vary from provider to provider, but Constellix offers less than one second propagation times. This cuts down on network overhead.
DNS Management vs DNS Hosting
The quick answer, DNS hosting is a service that stores the records for your domain. DNS management is also DNS hosting, but also offers additional services that allow you to create rules that influence how querying clients are routed. Services include: Failover, GeoDNS, load balancing, etc.
Resolver
A resolver (or resolving name server) is the client-side of DNS. The resolver usually resides with your ISP and is responsible for actually making the queries for the querying client and the response from the authoritative DNS is returned to the resolver and then passed to the querying client.