Objective 1.2: Common Ports

Objective 1.2: Identify commonly used TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) default ports

See Objective 1.1: Common Protocols for information on the protocols that communicate using these ports.

TCP (Transmission Control Protocol) ports

Port	Protocol
20	FTP (File Transfer Protocol)
21	FTP (File Transfer Protocol)
22	SSH (Secure Shell)
23	Telnet
25	SMTP (Simple Mail Transfer Protocol)
53	DNS (Domain Name System)
80	HTTP (Hypertext Transfer Protocol)
110	POP3 (Post Office Protocol version 3)
123	NTP (Network Time Protocol)
143	IMAP4 (Internet Message Access Protocol version 4)
443	HTTPS (Hypertext Transfer Protocol Secure)
3389	RDP (Remote Desktop Protocol)

UDP (User Datagram Protocol) ports

Port	Protocol
53	DNS (Domain Name System)
67	BOOTP/DHCP (Bootstrap Protocol/Dynamic Host Configuration Protocol)
69	TFTP (Trivial File Transfer Protocol)
161	SNMP (Simple Network Management Protocol)