Sobes.tech
Intern

What is a hostname and port?

sobes.tech AI

Answer from AI

The hostname and port are two key components used for identifying and accessing network resources.

Hostname is a unique human-readable identifier for a device or server on a network. It can be:

  • Fully Qualified Domain Name (FQDN): for example, www.google.com, which includes the hostname (www) and the domain name (google.com).
  • Local hostname: for example, MyPC or WebServer, used within a local network.

The Domain Name System (DNS) translates the hostname into an IP address needed for routing data on the network.

Port is a numerical value (from 1 to 65535) used to identify a specific process or application running on a server. When data arrives at a specific IP address, the port indicates which application should handle this data.

  • Well-known ports (1-1023) are reserved for standard network services (e.g., 80 for HTTP, 443 for HTTPS, 22 for SSH).
  • Registered ports (1024-49151) can be registered by organizations for their applications.
  • Dynamic/private ports (49152-65535) are used temporarily by clients when establishing connections or for specific applications.

The combination of an IP address (or hostname) and port uniquely identifies a specific service on a specific machine in the network.

Example: When requesting a webpage http://www.google.com:80/, you use:

  • Hostname: www.google.com (which is translated into an IP address)
  • Port: 80 (the standard port for HTTP)

This indicates the need to connect to the web server (www.google.com) via the HTTP protocol (through port 80) to retrieve the requested page.