UDP 20
UDP port 20 protocol information and warnings.
Looking for information on Protocol UDP 20? This page will attempt to provide you with as much port information as possible on UDP Port 20.
UDP Port 20 may use a defined protocol to communicate depending on the application. A protocol is a set of formalized rules that explains how data is communicated over a network. Think of it as the language spoken between computers to help them communicate more efficiently.
Protocol HTTP for example defines the format for communication between internet browsers and web sites. Another example is the IMAP protocol that defines the communication between IMAP email servers and clients or finally, the SSL protocol which states the format to use for encrypted communications.
UDP Port 20
Here is what we know about protocol UDP Port 20. If we do not have any information on port 20 in our database, a counter will be set for UDP port 20. After enough hits, we'll research this port and update the database.
If you have information on UDP port 20 that is not reflected in our database, please leave a comment or post your information on our Web Security Forum. We'll update our database so that the next user searching for port 20 will have the most accurate information.
PORT 20 - Information
| Port Number: | 20 |
| TCP / UDP: | UDP |
| Delivery: | No |
| Protocol / Name: | ftp-data |
| Port Description: | This is the FTP service's default data transfer port; required inbound if internal users are allowed access to external FTP sites, yet open port poses a threat (hole for network mapping, etc). Modern firewalls solve this by keeping it closed until a valid FTP session exists, then only opening it between those hosts. Control via a stateful-tracking firewall, do not simply open at perimeter. |
| Virus / Trojan: | No |
Side note: UDP port 20 uses the Datagram Protocol, a communications protocol for the Internet network layer, transport layer, and session layer. This protocol when used over PORT 20 makes possible the transmission of a datagram message from one computer to an application running in another computer. Like TCP (Transmission Control Protocol), UDP is used with IP (the Internet Protocol) but unlike TCP on Port 20, UDP Port 20 is connectionless and does not guarantee reliable communication; it's up to the application that received the message on Port 20 to process any errors and verify correct delivery.
UDP 20 - Disclaimer
We do our best to provide you with accurate information on PORT 20 and work hard to keep our database up to date. This is a free service and accuracy is not guaranteed. We do our best to correct any errors and welcome feedback!