what is a port?
Port
In networking, a "port" refers to a logical endpoint or communication channel used for network services on a computer or device. It is a numerical value that, along with the IP address, helps identify a specific process or service to which network traffic should be directed. Ports enable multiple services to operate on a single device, and they are crucial for facilitating communication between different devices on a network.
A port is a crucial element in networking that helps direct data to the appropriate service or process on a device. Understanding port numbers and their associated services is essential for configuring network services, implementing security measures, and troubleshooting network issues.
COMMON PORTS
PORTS
PORT 22
SSH (Secure Shell):
- Port: 22
- Protocol: TCP
- Used for secure remote access to the system.
PORT 80
HTTP (Hypertext Transfer Protocol):
- Port: 80
- Protocol: TCP
- Used for unencrypted web traffic.
PORT 443
HTTPS (Hypertext Transfer Protocol Secure):
- Port: 443
- Protocol: TCP
- Used for encrypted web traffic.
PORTS
Think of a port like a door on a computer. Imagine a building (the computer) with different doors (ports) for different services or tasks. Each door has a number (port number) to help people (data) find the right place inside the building.
PORT 21
FTP (File Transfer Protocol):
- Port: 21 (Control), 20 (Data)
- Protocol: TCP
- Used for transferring files between systems.
PORT 22
SFTP (SSH File Transfer Protocol):
- Port: 22
- Protocol: TCP
- Provides secure file transfer over SSH.
PORT 25
SMTP (Simple Mail Transfer Protocol):
- Port: 25
- Protocol: TCP
- Used for sending email.
common ports
PORTS
PORT 143
IMAP (Internet Message Access Protocol):
- Port: 143
- Protocol: TCP
- Used for retrieving email from a mail server.
PORT 110
POP3 (Post Office Protocol version 3):
- Port: 110
- Protocol: TCP
- Used for retrieving email from a mail server.
PORT 53
DNS (Domain Name System):
- Port: 53
- Protocol: UDP/TCP
- Resolves domain names to IP addresses.
PORTS
PORT 123
NTP (Network Time Protocol):
- Port: 123
- Protocol: UDP
- Synchronizes system clocks over a network.
PORT 67
DHCP (Dynamic Host Configuration Protocol):
- Port: 67 (Server), 68 (Client)
- Protocol: UDP
- Assigns IP addresses dynamically to network devices.
PORT 2049
NFS (Network File System):
- Port: 2049
- Protocol: TCP/UDP
- Used for sharing files and directories between systems.