AHTR Networks

Network Ports

Ports are used for communication between computers.
If the analogy where an IP address is equal to a building's street address, ports can be thought of as telephone numbers which go into that specific 'building'. However, each 'building' has its own set of numbers (ports) which may not apply elsewhere.

Port Ranges

Ports are divided into specific ranges:

Common Ports

Often, ports can be used to determine what kind of application is running or listening on a specific port. Here is a list of commonly used ports on the Internet. It is impossible to list every single use for a port since applications are not always registered. The IANA handles the registration of ports, and most of the data in the following table is sourced from the official assignments.

Port #TransportDescription
1TCP/UDPTCP Port Service Multiplexer
5TCP/UDPRemote Job Entry
7TCP/UDPECHO Protocol
9TCP/UDPDISCARD Protocol
13TCP/UDPDAYTIME Protocol
14TCP/UDPNETSTAT Protocol
20TCPFTP Data
21TCPFTP Control
22TCP/UDPSSH
23TCP/UDPTelnet
25TCP/UDPSMTP
37TCP/UDPTIME Protocol
42TCP/UDPHost Name Server / WINS
43TCPWHOIS
53TCP/UDPDomain Name System
56TCP/UDPRoute Access Protocol
67UDPBOOTP / DHCP
68UDPBOOTP / DHCP
69UDPTFTP
70TCPGopher
79TCPFinger
80TCPHTTP
88TCPKerberos
109TCPPOP2
110TCPPOP3
115TCPSimple FTP
119TCPNewsgroups NNTP
123UDPNetwork Time Protocol NTP
137TCP/UDPNetBIOS Name
138TCP/UDPNetBIOS Datagram
139TCP/UDPNetBIOS Session
143TCP/UDPIMAP4
153TCP/UDPSimple Gateway Monitoring Protocol SGMP
161TCP/UDPSimple Network Management Protocol SNMP
162TCP/UDPSNMP-TRAP
194TCPInternet Relay Chat IRC
213TCP/UDPIPX
220TCP/UDPIMAP3
264TCP/UDPBorder Gateway Multicast Protocol BGMP
389TCP/UDPLightweight Directory Access Protocol LDAP
443TCPHTTPS
444TCP/UDPSimple Network Paging Protocol SNPP
445TCP/UDPMicrosoft: SMB, Active Directory
512TCP/UDPLogin / Who
514TCP/UDPRSH / Syslog
515TCPLine Printer Daemon LPD
517UDPTalk
520UDPRouting Information Protocol RIP
530TCP/UDPRemote Procedure Call RPC
531TCP/UDPAIM / IRC
546TCP/UDPDHCPv6 Client
547TCP/UDPDHCPv6 Server