Default ports refer to standard port numbers associated with common network services and protocols. These default ports are used as standardized communications endpoints, making it easy for devices and applications to know where to send and receive data. Here are some common default ports and the services or protocols they are associated with:
HTTP (Hypertext Transfer Protocol):
- Default Port: 80
- Purpose: Used for transmitting web pages and other web resources on the World Wide Web.
HTTPS (HTTP Secure):
- Default Port: 443
- Purpose: Provides secure and encrypted communication over the web, commonly used for secure websites (e.g., online banking, e-commerce).
FTP (File Transfer Protocol):
- Default Ports: 20 (data transfer) and 21 (control)
- Purpose: Used for transferring files between a client and a server over a network.
SSH (Secure Shell):
- Default Port: 22
- Purpose: Provides secure, encrypted remote access and command-line control of a device or server.
SMTP (Simple Mail Transfer Protocol):
- Default Port: 25
- Purpose: Used for sending email messages from a client to a mail server or between mail servers.
POP3 (Post Office Protocol version 3):
- Default Port: 110
- Purpose: Retrieves email messages from a mail server to a client device.
IMAP (Internet Message Access Protocol):
- Default Port: 143
- Purpose: Allows email clients to access and manage email messages stored on a mail server.
DNS (Domain Name System):
- Default Ports: 53 (both UDP and TCP)
- Purpose: Resolves human-readable domain names (e.g., www.example.com) to IP addresses.
SNMP (Simple Network Management Protocol):
- Default Ports: 161 (UDP, SNMP agents) and 162 (UDP, SNMP managers)
- Purpose: Used for network monitoring and management.
RDP (Remote Desktop Protocol):
- Default Port: 3389
- Purpose: Provides remote access and control of Windows-based systems.
Telnet:
- Default Port: 23
- Purpose: Allows remote terminal access and command-line control of a device (often used for testing and troubleshooting).
HTTPS Proxy (HTTP over TLS/SSL):
- Default Port: 8080
- Purpose: Used as a proxy server for secure web traffic (HTTPS).
These default ports are widely recognized in the networking world, but it is important to note that in some cases, alternate ports may be used to run these services for various reasons, including security or optimization. Network administrators and users can configure services to use non-standard ports based on their specific needs.