Ports

Question 1

FTP

Answer 1

20/21, File Transfer Protocol, TCP, 21 is a control port that establishes the framework of the connection and 20 transfers the files

Question 2

SSH

Answer 2

22, TCP, transmits data securely through a remote connection, can remotely configure servers and other devices. Often used in linux and unix machines

Question 3

SMTP

Answer 3

25, Simple Mail Transfer Protocol, TCP, mail protocol that connects email clients to mail servers

Question 4

SSH file transfer protocol

Answer 4

22, TCP, completely separate from FTP and uses SSH to encrypt file transfers

Question 5

TACACS+

Answer 5

49, TCP, Cisco proprietary protocol used for AAA services authentication authorization accounting for Cisco devices specifically

Question 6

DNS

Answer 6

53, Domain Name System, UDP, associates IP addresses with domain names

Question 7

DHCP

Answer 7

67/68, Dynamic Host Configuration Protocol, UDP, commonly used by home routers to assign multiple local private IP addresses from one public IPv4 address

Question 8

HTTP

Answer 8

80, Hypertext Transfer Protocol, TCP, used for most websites and internet traffic

Question 9

Kerberos

Answer 9

88, TCP/UDP, network authentication protocol that allows for communication over a non secure network. Primarily uses UDP but can use TCP

Question 10

POP

Answer 10

110, Post Office Protocol, TCP, email protocol that allows email clients to communicate with email servers. POP provides only one way communication

Question 11

NTP

Answer 11

123, Network Time Protocol NTP, UDP, used to synchronize multiple devices with a standardized clock

Question 12

SMB

Answer 12

139, Server Message Block SMB, UDP, built on NetBIOS, used by windows devices to remotely access servers

Question 13

IMAP

Answer 13

143, Internet Message Access Protocol IMAP, TCP, email protocol that allows two way communication between email clients and servers

Question 14

SNMP

Answer 14

161/162, Simple Network Management Protocol SNMP, UDP, allows you to monitor usage statistics and health of devices on your network

Question 15

LDAP

Answer 15

389, Lightweight Directory Access Protocol LDAP, UDP, used to query directories unsecure

Question 16

HTTPS

Answer 16

443, Hypertext Transfer Protocol Secure HTTPS, TCP, secure version of HTTP that used TLS for encryption. Most websites use this instead of HTTP

Question 17

SSTP

Answer 17

443, Secure Socket Tunneling Protocol SSTP, TCP, developed to replace PPTP or L2TP/IPSec, uses TLS

Question 18

SMB (TCP)

Answer 18

445, Server Message Block (SMB), TCP, forces SMB to use TCP and adds encryption to the connection

Question 19

IPSec

Answer 19

500, Internet Protocol Security IPSec using ISAKMP, UDP, IP security achieved through use of Internet Security Association and Key Management Protocol, primarily used for VPNs

Question 20

SMTPS

Answer 20

587, Simple Mail Transfer Protocol Secure SMTPS, TCP, secure version of SMTP that uses TLS for encryption

Question 21

LDAPS

Answer 21

636, Lightweight Directory Access Protocol Secure LDAPS, TCP, secure LDAP that uses TLS for encryption

Question 22

FTPS

Answer 22

989/990, File Transfer Protocol Secure FTPS, TCP, FTP that uses TLS for encryption. It can run on 20/21 but is sometimes allocated to 989/990

Question 23

IMAPS

Answer 23

993, Internet Message Access Protocol Secure IMAPS, TCP, secure IMAP uses TLS for encryption

Question 24

POP3S

Answer 24

995, Post Office Protocol 3 Secure POP3S, TCP, secure version of POP that uses TLS for encryption

Question 25

RADIUS

Answer 25

1812/1813, Remote Authentication Dial In User Service RADIUS, UDP, used to provide AAA for network services

Question 26

RDP

Answer 26

3389, Remote Desktop Protocol RDP, TCP, used by windows devices for remote connections to other computers

Question 27

Diameter

Answer 27

3868, Diameter, TCP, developed as an upgrade to RADIUS

Question 28

SRTP

Answer 28

5004, Secure Real Time Protocol SRTP, UDP, replaces RTP used for streaming audio and video using UDP

Question 29

PPTP

Answer 29

1723, Point to Point Tunneling Protocol PPTP, TCP, based on PPP, deprecated protocol for VPNs

Question 30

L2TP

Answer 30

1701, Layer 2 Tunneling Protocol L2TP, UDP, used to create point to point connections like VPNs over a UDP connection. Needs IPsec for encryption. Designed as an extension to PPTP. Operates at the data link layer but encapsulates packets at the session layer.