Ports

Question 1

Port 20, 21

Answer 1

File Transfer Protocol FTP.
Transfers computer files between a client and server on a computer network.
Unsecured method.
Data transferred in the clear.

Question 2

Port 22

Answer 2

Secure Shell, SSH.
Cryptographic network protocol for operating network services securely over an unsecured network.
Best known for remote login to computer systems by users.

Question 3

Port 22

Answer 3

SSH File Transfer Protocol, SFTP.
Provides file access, file transfer, and file management over any reliable data stream.

Question 4

Port 23

Answer 4

Telnet.
Provides bidirectional interactive text-oriented communication facility using a virtual terminal connection.
Like SSH, but insecure.

Question 5

Port 25

Answer 5

Simple Mail Transfer Protocol, SMTP.
Internet standard for sending email.
RFC 821 was defined originally in 1982.
RFC 5321 developed in 2008 (current version).

Question 6

Port 53

Answer 6

Domain Name Service, DNS.
Hierarchical decentralized naming system for computers, services, or other resources connected to the internet or a private network.
Converts domain names to IP addresses.

Question 7

Port 67, 68

Answer 7

Dynamic Host Control, DHCP.
DHCP server dynamically assigns an IP addresses and networking parameters automatically.
Reduces burden on network admin.

Question 8

Port 69

Answer 8

Trivial File Transfer, TFTP.
Transmits files in both directions of a client-server application.
Used for booting an OS from a local area network file server.
Doesn’t provide user authentication or directory visibility.
Essentially a stripped-down version of FTP.

Question 9

Port 80

Answer 9

HyperText Transfer, HTTP.
Foundation of data communication for WWW.
Designed for distribution, collaborative, and hypermedia presentation across many devices.

Question 10

Port 110

Answer 10

Post Office Protocol v3, POP3.
Used by local email clients to retrieve email from a remote server over TCP/IP connection.

Question 11

Port 123

Answer 11

Network Time Protocol.
Provides clock synchronization between computer systems over packet-switched, variable-latency data networks.
Created in 1985, one of the oldest internet protocols in current use.

Question 12

Port 139

Answer 12

NetBios.
Network Basic input/output system.
Provides services allowing applications on separate computers to communicate over a local area network for file and printer sharing.

Question 13

Port 143

Answer 13

Internet Message Access Protocol, IMAP.
Provides email clients to retrieve email messages from a mail server over a TCP/IP connection.

Question 14

Port 161

Answer 14

Simple Network Management, SNMP.
Provides collection and organization of info about managed devices on IP networks.
Can modify that info to change device behavior, commonly used in network devices.

Question 15

Port 389

Answer 15

Lightweight Directory Access, LDAP.
Open, vendor-neutral, industry standard for accessing and maintaining distributed directory info services.

Question 16

Port 443

Answer 16

HTTP Secure, HTTPS.
Foundation of e-commerce on WWW.
Designed for adding security to the insecure HTTP protocol.

Question 17

Port 445

Answer 17

Server Message Block, SMB.
Provides shared access to files, printers, and misc. communications between devices on a network.

Question 18

Port 514

Answer 18

System Logging Protocol, Syslog.
Used to send logging data back to a centralized server.

Question 19

Port 587

Answer 19

Simple Mail Transfer Protocol Transport Layer Security, SMTP TLS.
Secure and encrypted way to send emails.

Question 20

Port 636

Answer 20

LDAP Secure, LDAPS.
Open, vendor-neutral, industry standard for accessing and maintaining distributed directory information services.
Provides secure directory services

Question 21

Port 993

Answer 21

Internet Message Access Protocol over SSL, IMAP over SSL.
Secure and encrypted way to receive emails.

Question 22

Port 995

Answer 22

Post Office Protocol v3 over SSL, POP3 over SSL.
Secure and encrypted way to receive emails.

Question 23

Port 1433

Answer 23

Structured Query Language Server Protocol, SQL.
Used for communication from a client to the database engine.

Question 24

Port 1521

Answer 24

SQLnet Protocol.
Used for communication from a client to the database engine.

Question 25

Port 3306

Answer 25

MySQL.
Used for communication from a client to the MySQL database engine.

Question 26

Port 3389

Answer 26

Remote Desktop Protocol, RDP.
Proprietary protocol developed by MS.
Provides a user with a graphical interface to connect to another computer over a network connection.
User employs RDP client software for this purpose and the other computer must run RDP server software.

Question 27

Port 5060, 5061

Answer 27

Session Initiation Protocol, SIP.
Provides signaling and controlling multimedia communication sessions in applications.
Used for internet telephony for voice and video calls, VOIP, and instant messaging.