What’s the Difference Between a Domain and Host?

The name can be examined to identify a domain and differentiate it from the host. The host falls within a domain and is usually the first part of the string, before the first dot. The rest of the string is the domain.

Domains

Domains are among the assets that are mapped and attributed to companies in the Bitsight platform. They serve as containers for multiple hosts and can be parents to subdomains. Domains have entry records with domain registrars, such as GoDaddy.

Attributes of a domain:

• The domain can also be a hostname.

  Example: saperix.com resolves to the same IP address as www.saperix.com

• Domains can be parents to subdomains. This makes it difficult to distinguish them from one another.

  Example: marketing.saperix.com could be a subdomain of saperix.com. It could also be a host. If there’s another level, e.g., www.marketing.saperix.com, then marketing is an indicator of it being a subdomain and www is the host.

Hosts

In computer networking, a hostname (nodename) is a label assigned to a device connected to a computer network. It’s used to identify the device for local use, as well as on the Internet. When used locally, hostnames may be bare (e.g., mycomputer), part of an active directory, or internal domain (such as mycomputer.acmerocketskates.com).

Hostnames on the Internet belong to a domain in the public Domain Name System (DNS), together with the IP addresses of the host they represent, for the purpose of mapping the hostname to an address or the reverse process.

Attributes of a host:

• Hosts resolve to one or more IP addresses or other hostnames with aliases known as a canonical name (CNAME) resource record in DNS.
• It can be difficult to distinguish hostnames from domains since they can either consist of a single word or can be a structured phrase.

  Example: Depending on how DNS zones are configured, the hostname of www.marketing.saperix.com could either be:

  • The www under the marketing.saperix.com domain.
  • Under the saperix.com domain.

• Internet hostnames have the DNS domain appended to them, separated from the host-specific label by a dot.
• The hostname is also considered as the domain name and the domain name is almost always fully specified by including the entire DNS path to the top-level domain.
• The entire name, including the hostname, is considered the fully qualified domain name (FQDN).

  Example: If www.marketing.saperix.com is an FQDN:

  • www is the hostname.
  • marketing.saperix.com is the internet domain.
  • com is the top-level domain.