IP Address & Ports

What is an IP Address?

An IP address is a unique identifier assigned to every device that communicates over the Internet. It distinguishes each device and allows it to be located on the network. An IP address consists of four numeric segments separated by periods. For example:

206.13.28.12

Think of your IP address like your phone number: it’s what allows others to find your device over the network.

What are Ports?

In TCP/IP networking, ports act as endpoints for logical connections. When you access a website, your computer opens a connection to a specific port on the server to request web pages. There are a total of 65,535 ports available, each used for different types of communication.

Common Ports and Their Uses

Port Number Description
1TCP Port Service Multiplexer (TCPMUX)
5Remote Job Entry (RJE)
7ECHO
18Message Send Protocol (MSP)
20FTP — Data
21FTP — Control
22SSH Remote Login Protocol
23Telnet
25Simple Mail Transfer Protocol (SMTP)
29MSG ICP
37Time
42Host Name Server (Nameserv)
43WhoIs
49Login Host Protocol (Login)
53Domain Name System (DNS)
69Trivial File Transfer Protocol (TFTP)
70Gopher Services
79Finger
80HTTP
103X.400 Standard
108SNA Gateway Access Server
109POP2
110POP3
115Simple File Transfer Protocol (SFTP)
118SQL Services
119Newsgroup (NNTP)
137NetBIOS Name Service
139NetBIOS Datagram Service
143Interim Mail Access Protocol (IMAP)
150NetBIOS Session Service
156SQL Server
161SNMP
179Border Gateway Protocol (BGP)
190Gateway Access Control Protocol (GACP)
194Internet Relay Chat (IRC)
197Directory Location Service (DLS)
389Lightweight Directory Access Protocol (LDAP)
396Novell Netware over IP
443HTTPS
444Simple Network Paging Protocol (SNPP)
445Microsoft-DS
458Apple QuickTime
546DHCP Client
547DHCP Server
563SNEWS
569MSN
1080Socks