Common Ports

Question 1

Telnet - Telecommunication Network

Answer 1

tcp/23

Question 2

SSH - Secure Shell

Answer 2

tcp/22

Question 3

DNS - Domain Name System

Answer 3

udp/53

Question 4

SMTP - Simple Mail Transfer Protocol

Answer 4

tcp/25

Question 5

SFTP - Secure File Transfer Protocol

Answer 5

tcp/22

Question 6

FTP - File transfer protocol

Answer 6

tcp/20 (Active mode data)

tcp/21 (Control)

Question 7

TFTP - trivial file transfer protocol

Answer 7

udp/69

Question 8

DHCP - dynamic host configuration protocol

Answer 8

udp /67

udp /68

Question 9

HTTP - Hypertext transfer protocol

Answer 9

tcp /80

Question 10

HTTPS - hypertext transfer protocol secure

Answer 10

tcp /443

Question 11

SNMP - simple network management protocol

Answer 11

udp /161

Question 12

RDP - Remote desktop protocol

Answer 12

tcp /3389

Question 13

NTP - Network time protocol

Answer 13

udp /123

Question 14

SIP - Session initiation protocol

Answer 14

tcp /5060

tcp /5061

Question 15

SMB - Server message block

Answer 15

tcp /445 (NetBIOS-less)

Question 16

POP3 - Post office protocol V3

Answer 16

tcp /110

Question 17

IMAP4 - Internet message access protocol v4

Answer 17

tcp /143

Question 18

LDAP - Light weight directory access protocol

Answer 18

tcp /389

Question 19

LDAPS - Lightweight directory access protocol secure

Answer 19

tcp /636

Question 20

H. 323

Answer 20

tcp /1720