Well-Known Ports

Question 1

Port 20

Answer 1

File Transfer protocol (FTP) - Data Connection

Question 2

Port 21

Answer 2

File Transfer Protocol (FTP) - Control Connection

Question 3

Port 22

Answer 3

Secure Shell (SH)

Question 4

Port 23

Answer 4

Telnet

Question 5

Port 25

Answer 5

Simple Mail transfer Protocol (SMTP)

Question 6

Port 53

Answer 6

Domain Name System (DNS)

Question 7

Port 67

Answer 7

Dynamic Host Configuration Protocol (DHCP) Server

Question 8

Port 68

Answer 8

Dynamic Host Configuration Protocol (DHCP) Client

Question 9

Port 69

Answer 9

Trivial File Transfer Protocol (TFTP)

Question 10

Port 80

Answer 10

Hypertext Transfer Protocol (HTTP)

Question 11

Port 110

Answer 11

Post Office Protocol (POP)

Question 12

Port 137 - 139

Answer 12

NetBIOS (Network Basic Input/Output System) over TCP/IP

Question 13

Port 143

Answer 13

Internet Mail Access Protocol (IMAP)

Question 14

Port 161

Answer 14

Simple Network Management Protocol (SNMP)

Question 15

Port 162

Answer 15

Simple Network Management Protocol (SNMP) Trap Operation

Question 16

Port 389

Answer 16

Lightweight Directory Access Protocol (LDAP)

Question 17

Port 427

Answer 17

Service Location Protocol (SLP)

Question 18

Port 443

Answer 18

Hypertext Transfer Protocol Secure (HTTPS)

Question 19

Port 445

Answer 19

Server Message Block (SMB)

Question 20

Port 3389

Answer 20

Remote Desktop Protocol (RDP)

Question 21

How many-known protocols are there?

Answer 21

18

Question 22

What are the UDP-only Port numbers?

Answer 22

67, 68, 69, 161, and 162

Question 23

What are the three well-known UDP-only protocols?

Answer 23

Dynamic Host Configuration Protocol (DHCP)
Simple Network Management Protocol (SNMP)
Trivial File Transfer Protocol (TFTP)

Question 24

What are the two TCP/UDP protocols?

Answer 24

Domain Name System
NetBIOS over TCP/IP

Question 25

TFTP

Answer 25

Trivial File Transfer Protocol

Question 26

SLP

Answer 26

Service Location Protocol