A+ Port Numbers And Explanation

FTP

The File Transfer Protocol a standard communication protocol used for the transfer of computer files from a server to a client on a computer network.

SSH

The Secure Shell Protocol is an encrypted network protocol for operating network services securely over an unsecured network. (Remote login and command-line execution)

Telnet

A protocol that provides a command line interface for communication with a remote device or server. (Unsecure Shell)

SMTP

The Simple Mail Transfer Protocol is an application used by mail servers to send, receive, and relay outgoing email between senders and receivers.

DNS

Domain Name System which turns domain names into IP addresses, (google.com to 172.253.122.101) which allow browsers to get to websites and other internet resources.

RDP

Remote Desktop Protocol, a secure network communication protocol offered by Microsoft, allows users to execute remote operations on other computers.

POP3

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.

IMAP

Internet Messaging Access Protocol stores email messages on a mail server and enables the recipient to view and manipulate them as though they were stored locally on their device(s). Users can log in via multiple email clients on computers or mobile device and read the same messages.

IMAP Secure

HTTP

The Hypertext Transfer Protocol is the foundation of the World Wide Web, and is used to load webpages using hypertext links.

HTTPS

Hypertext Transfer Protocol Secure is an extension of the Hypertext Transfer Protocol and uses encryption for secure communication over a computer network, and is widely used on the Internet.

NetBIOS/NetBT Name Service

NetBIOS/NetBT Datagram

NetBIOS/NetBT Session Service

SMB/CIFS

The Server Message Block protocol is a network file sharing protocol mainly used by Microsoft Windows equipped computers normally used to share files, printers, serial ports, and miscellaneous communications between nodes on a network.

Common Internet File System is a network filesystem protocol used for providing shared access to files and printers between machines on the network. The key difference between CIFS and SMB is that CIFS is a dialect of SMB – a particular implementation of the SMB protocol.

SLP

The Service Location Protocol is a service discovery protocol that allows computers and other devices to find services in a local area network without prior configuration.

AFP

Apple Filing Protocol the standard file sharing protocol used in the Mac. Starting with Mac OS X, AFP uses TCP/IP as the primary communications protocol.

DHCP Server side (outgoing from client)

DHCP Client side (outgoing from server)

Dynamic Host Configuration Protocol (DHCP) is a client/server protocol that automatically provides an Internet Protocol (IP) host with its IP address and other related configuration information such as the subnet mask and default gateway.