ISC2 CC Exam - Network Ports

Ports 137, 138, 139

NetBIOS - Windows systems use ports 137-139 for network communications using the NetBIOS protocol

Port 110

POP (Post Office Protocol) - POP transfers emails from the server to the client, allowing you to read them even if you are not connected to the internet.

Port 3389

Remote Desktop Protocol (RDP) - Uses port 3389 to provide a user with a GUI to connect to another computer over a network connection

Port 25

SMTP (Simple Mail Transfer Protocol) - SMTP is a widely used TCP protocol for email sending. The SMTP protocol is mainly used by the clients to send emails to the servers or for the email communications between servers.

Port 22

Secure Shell (SSH) - Uses port 22 to for encrypted administrative connections to servers

Port 21

File Transfer Protocol (FTP) - Uses port 21 to transfer data between systems

Port 80

HTTP (Hypertext Transfer Protocol) - Uses port 80 for unencrypted web communications

Port 443

HTTPS (Hyper Text Transfer Protocol Secure) - Uses port 443 for encrypted connections

Port 53

DNS: Domain Name System - All systems use port 53 for DNS lookups. Translates domain names to IP addresses

Port 143

IMAP (Internet Message Access Protocol) - IMAP is a protocol for receiving emails from a server. Since IMAP allows access to emails from multiple locations simultaneously, it keeps the email on the server after being delivered.