CCNA Ports & Protocols

Question 1

FTP

Answer 1

20, 21 -
FTP (File Transfer Protocol) is a standard network protocol used for the transfer of files from one host to another over a TCP-based network, such as the Internet. FTP works by opening two connections that link the computers trying to communicate with each other.

Question 2

SSH, SFTP

Answer 2

22 - Secure Shell (SSH) is a cryptographic protocol that allows users to securely access, manage, and transfer data remotely over an unsecured network. SSH is commonly used by network administrators to manage systems and applications.

Question 3

TELNET

Answer 3

23 - Telnet is a network protocol used to virtually access a computer and provide a two-way, collaborative and text-based communication channel between two machines. It follows a user command TCP/IP networking protocol that creates remote sessions.

Question 4

SMTP

Answer 4

25 - SMTP stands for Simple Mail Transfer Protocol. It is a communication protocol used for sending and receiving email messages over the Internet. Mail servers and other message transfer agents (MTAs) use SMTP to send, receive and relay mail messages.

Question 5

DNS

Answer 5

53 - The Domain Name System (DNS) translates domain names into IP addresses, allowing users to access websites using human-readable names.

Question 6

DHCP

Answer 6

67, 68 - Dynamic Host Configuration Protocol (DHCP) is a network protocol that automatically assigns IP addresses and other configuration information to devices on a network. This allows devices to communicate with each other and the internet.

Question 7

TFTP

Answer 7

69 - Trivial File Transfer Protocol (TFTP) is a simple protocol that provides basic file transfer function with no user authentication. TFTP is intended for applications that do not need the sophisticated interactions that File Transfer Protocol (FTP) provides.

Question 8

HTTP

Answer 8

80 - HTTP is the primary protocol for transmission of information across the internet. Information is exchanged between clients and servers in the form of hypertext documents, from which HTTP gets its name.

Question 9

POP3

Answer 9

110 - POP3 is an older protocol that was originally designed to be used on only one computer. Unlike modern protocols that use two-way synchronization, POP3 only supports one-way email synchronization, only allowing users to download emails from a server to a client.

Question 10

NTP

Answer 10

123 - Network Time Protocol (NTP) is a protocol that synchronizes the clocks of devices on a network. This is important for many applications, including network management, billing systems, and collaborative processing.

Question 11

NetBIOS

Answer 11

137 - 139 - NetBIOS is an abbreviation of Network Basic Input/Output System. The primary purpose of NetBIOS is to allow applications on separate computers to communicate and establish sessions to access shared resources, such as files and printers, and to find each other over a local area network (LAN).

Question 12

IMAP

Answer 12

143 - (Internet Messaging Access Protocol) Users can log in via multiple email clients on computers or mobile device and read the same messages. All changes made in the mailbox will be synced across multiple devices and messages will only be removed from the server if the user deletes the email.

Question 13

SNMP

Answer 13

161 - Simple Network Management Protocol (SNMP) is a networking protocol used for the management and monitoring of network-connected devices in Internet Protocol networks.

Question 14

LDAP

Answer 14

389 - Lightweight directory access protocol (LDAP) is a protocol that helps users find data about organizations, persons, and more. LDAP has two main goals: to store data in the LDAP directory and authenticate users to access the directory.

Question 15

HTTPS

Answer 15

443 - HTTPS works to protect and encrypt nearly all the information sent from a user to a website. The URL path, post bodies, and query string parameters are all encrypted when sent via an HTTPS connection.

Question 16

SMB

Answer 16

445 - The Server Message Block protocol (SMB protocol) is a client-server communication protocol used for sharing access to files, printers, serial ports and other resources on a network.

Question 17

LDAPS

Answer 17

636 - Lightweight directory access protocol (LDAP) is a protocol that helps users find data about organisations, persons, and more. LDAP has two main goals: to store data in the LDAP directory and authenticate users to access the directory.

Question 18

H.323

Answer 18

1720 - H. 323 is a recommendation from the ITU Telecommunication Standardisation Sector (ITU-T) that defines the protocols to provide audio-visual communication sessions on any packet network.

Question 19

MGCP

Answer 19

2427/2727 - Media Gateway Control Protocol (MGCP), commonly known as H. 248, is a standard protocol for handling the signaling and session management needed during a multimedia conference.

Question 20

RDP

Answer 20

3389 - TCP port 3389 is used for Remote Desktop Protocol (RDP), a proprietary protocol developed by Microsoft that allows users to connect to a remote computer over a network connection.

Question 21

RTP

Answer 21

5004/5005 - Real-time Transport Protocol (RTP) is a network standard designed for transmitting audio or video data that is optimised for consistent delivery of live data.

Question 22

SIP

Answer 22

5060/5061 - Session Initiation Protocol (SIP) is a set of rules that allows users to make and end connections over the internet, including voice calls, video conferences, and instant messaging.