Questions and Answers| Updated
2024/2025
**File Transfer Protocol (FTP)**
A networking protocol used to transfer files between computers over a TCP/IP network. Port 21.
FTP allows for both uploading and downloading files to and from a server.
**Post Office Protocol (POP3)**
A protocol used by email clients to retrieve emails from a mail server. Port 110.
POP3 allows users to download emails to their local devices for offline access.
**Simple Mail Transfer Protocol (SMTP)**
A protocol used to send emails from a client to a server or between servers. Port 25.
SMTP is essential for sending outgoing email messages.
**Internet Control Message Protocol (ICMP)**
A network protocol used for sending error messages and operational information. It’s commonly
used in ping operations.
ICMP helps diagnose network connectivity issues and troubleshoot network problems.
**Secure Hypertext Transfer Protocol (HTTPS)**
An extension of HTTP that uses encryption to secure data transmitted over the internet. Port 443.
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, HTTPS ensures secure communication between web browsers and servers.
**Network File System (NFS)**
A protocol that allows file access over a network in a way that is similar to local storage. Port
2049.
NFS enables users to share files and directories between different operating systems.
**Lightweight Directory Access Protocol (LDAP)**
A protocol used for accessing and maintaining distributed directory information services. Port
389.
LDAP is commonly used for user authentication and authorization in network environments.
**Internet Message Access Protocol (IMAP)**
A protocol used by email clients to retrieve emails from a mail server while allowing multiple
devices to access the same mailbox. Port 143.
IMAP provides more flexibility than POP3, as it allows users to manage their emails directly
on the server.
**Telnet**
A protocol used for remote access to network devices, allowing users to manage devices over a
TCP/IP network. Port 23.
Telnet provides a command-line interface to interact with remote systems.
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