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Port Numbers Comptia A+

18 community-sourced questions and answers. Free — no login.

Community-sourced. Answers may be wrong or out of date. Always verify with your official training portal before submitting. Not affiliated with any branch, agency, or vendor. Details.
QUESTION 1

Remote Desktop Protocol (RDP)

ANSWER

TCP/UDP 3389

QUESTION 2

File Transer Protocol (FTP)

ANSWER

TCP 20 Active mode/Data Transfer TCP 21 Control/Commands (Default)

QUESTION 3

Secure Shell (SSH)

ANSWER

TCP Port 22

QUESTION 4

Telnet

ANSWER

TCP Port 23

QUESTION 5

Simple Mail Transfer Protocol (SMTP)

ANSWER

Port 25

QUESTION 6

Domain Name System (DNS)

ANSWER

Port 53

QUESTION 7

Hypertext Transfer Protocol (HTTP)

ANSWER

Port 80

QUESTION 8

Post Office Protocol version 3 (POP3)

ANSWER

TCP Port 110

QUESTION 9

Internet Message Access Protocol (IMAP)

ANSWER

Port 143

QUESTION 10

Hyper Text Transfer Protocol Secure (HTTPS)

ANSWER

Port 443

QUESTION 11

Server Message Block (SMB)

ANSWER

Ports 137, 139, 445

QUESTION 12

Apple Filing Protocol (AFP)

ANSWER

Port 548

QUESTION 13

NetBIOS (Network Basic Input/Output System)

ANSWER

Ports 137, 138, 139

QUESTION 14

Service Location Protocol (SLP)

ANSWER

Port 427

QUESTION 15

Dynamic Host Configuration Protocol (DHCP)

ANSWER

Port 67/68

QUESTION 16

Lightweight Directory Access Protocol (LDAP)

ANSWER

Port 389

QUESTION 17

Simple Network Management Protocol (SNMP)

ANSWER

TCP Ports 161/162

QUESTION 18

What is the difference between TCP Ports and UDP Ports?

ANSWER

TCP and UDP are both transport layer protocols. TCP is a connection orientated protocol and provides reliable message transfer. UDP is a connection less protocol and does not guarantee message delivery.

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