Ports and Protocols

Question 1

Port 20

Answer 1

FTP - Data
FTP uses two ports, one for control and one for data. The client initiates a session on the server’s control port (TCP:21), then the server initiates a session to the client from its data port (TCP:20).

Question 2

Port 21

Answer 2

FTP - Control
FTP uses two ports, one for control and one for data. The client initiates a session on the server’s control port (TCP:21), then the server initiates a session to the client from its data port (TCP:20).

Question 3

port 22

Answer 3

SSH
The Secure Shell Protocol is a cryptographic network protocol for operating network services securely over an unsecured network. Its most notable applications are remote login and command line execution.

Question 4

Port 23

Answer 4

Telnet
Telnet is an application protocol used on the internet or local area network to provide a bidirectional interactive text-oriented communication facility using a virtual terminal connection. User data is interspersed in-band with telnet control information in an 8-byte oriented data connection over TCP.

Question 5

Port 25

Answer 5

SMTP
The simple mail transfer protocol (SMTP) is an internet standard communication protocol for electronic mail transmission. Mail servers and other message transfer agents use SMTP to send and receive mail messages. User-level mail clents typically use SMTP only for sending messages to a mail server for relaying.

Question 6

Port 69

Answer 6

TFTP
Trivial File Transfer Protocol (TFTP) is a simple lockstep file transfer protocol which allows a client to get a file from or put a file onto a remote host. One of its primary uses is in the early stages of nodes booting from a local area network.

Question 7

Port 80

Answer 7

HTTP
Hypertext Transfer Protocol (HTTP) is an application layer protocol for transmitting hypermedia documents, such as HTML. It was designed for communication between web browsers and web servers, but it can also be used for other purposes.

Question 8

Port 161

Answer 8

SNMP
Simple Network Management Protocol (SNMP) is an internet standard protocol for collecting and organizing information about managed devices on IP networks and for modifying that information change device behaviour. Devices that typically support SNMP include, cable modems, routers, switches, servers, workstations, printers, and more.

Question 9

Port 179

Answer 9

Border Gateway Protocol (BGP)
Is a standardized exterior gateway protocol designed to exchange routing and reachability information among autonomous systems (AS) on the internet. BGP is classified as a path vector routing protocol, and it makes routing decisions based on paths, network policies, or rule-sets configured by a network administrator.

Question 10

Port 443

Answer 10

HTTPS is a secure extension of HTTP. It is used for secure communication over computer networks, and is widely used on the internet. In HTTPS the communication protocol is encrypted using TLS or, formerly SSL.

Question 11

Ports 546/547

Answer 11

DHCP Client / DHCP Server
Dynamic Host Configuration Protocol (DHCP) is a network management protocol used on internet protocol (IP) networks for automatically assigning Ip addresses and other communication parameters to devices connected to the network using a client-server architecture.