Search TCP / UDP Port Assignment Database

Search result for: 21

From: [IANA] [NMAP] [WG] [WP] [SANS]

Service	Port	Prot.	Description	Notes
ftp	21	tcp	File Transfer [Control]	[IANA] [RFC959]
ftp	21	udp	File Transfer [Control]	[IANA] [RFC959]
ftp	21	sctp	FTP	[IANA] [RFC4960]
ftp	21	sctp	# File Transfer [Control]	[NMAP]
ftp	21	tcp	# File Transfer [Control]	[NMAP]
ftp	21	udp	# File Transfer [Control]	[NMAP]
	21	tcp	ESX 3.x: from: ESX Host - to: FTP Server	[WG] FTP
	21	tcp	ESX 3.x: from: FTP Client - to: ESX Host	[WG] FTP
	21	tcp	ESX 4.x: from: ESX Host - to: FTP Server	[WG] FTP
	21	tcp	ESX 4.x: from: FTP Client - to: ESX Host	[WG] FTP
ftp	21	tcp/udp	File Transfer Protocol (FTP) port; sometimes used by File Service Protocol (FSP)	[WG]
	21	tcp	FTP control - Application Layer Gateway Service	[WG]
	21	tcp	FTP control - FTP Publishing Service	[WG]
	21		Oracle Files - FTP	[WG] 2100 or 21000
	21	tcp/sctp/udp	FTP�control (command)	[WP] Official
ftp	21	tcp	File Transfer (Control)	[SANS]
ftp	21	udp	File Transfer (Control)	[SANS]

How to use:

To search by port enter a number in the range between 0 and 65535. To search service / protocol description by keyword enter a text string at least three characters long. Wild-card (*) is supported if it is the last character in the search string. Alternatively, select a port from one of the ranges listed below.

Port range: 0-1023

0-1023 - Well-known or System Ports
1024-49151 - Registered or User Ports
49152-65535 - Dynamic/Private or Ephemeral Ports

Information Sources:
[IANA] IANA Service Name and Transport Protocol Port Number Registry
[NMAP] NMAP.org well known service port numbers
[WG] WintelGuy.com port number database compiled from many different sources, including Microsoft, VMWare, Citrix, Oracle, etc.
[WP] Wikipedia - List of TCP and UDP port numbers
[SANS] SANS Inst. / DShield service list