About
The Domain Name System (DNS) and the Canonical Name Record (CNAME) are both utilized when setting up a subdomain for landing pages or configuring an email sending domain.
In this Article
How Does it Work?
The DNS and CNAME work in conjunction with one another to effectively display domains and subdomains.
DNS
The DNS is a naming system utilized to identify computers throughout the Internet. The DNS maps human friendly domain names to IP addresses that are required for computers to locate and display content although DNS has been enhanced to perform other functions as well; users can think of the DNS as a sort of phone book for the Internet.
- For example, the domain name www.google.com translates to the IP address 74.125.142.100
The DNS can be quickly update thus allowing a service to update their location on a network without affecting users. The DNS is a central component in cloud based and content delivery networks (video streaming, software download, etc,).
CNAME
A CNAME is a resource record utilized within the DNS; a CNAME is often utilized to direct a subdomain on someone's domain to an external service. CNAME utilization is important when providing multiple services from one IP address; it allows for different host names to point to the same location.
- For example, www.example.net is a subdomain which utilizes a CNAME to map it to the domain of www.example.com.
When a DNS resolver (which initiates the translation of a domain name into an IP address) reviews a domain name and discovers a CNAME, it will restart the translation process and instead, use the CNAME instead of the original domain name.
- For example, if the domain name is bar.example.com, but the CNAME is foo.example.com, the DNS resolver will restart the process using the CNAME and return the IP Address for foo.example.com because it is the subdomain of bar.example.com.