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TCP 9

TCP port 9 protocol information and warnings.

Looking for information on Protocol TCP 9? This page will attempt to provide you with as much port information as possible on TCP Port 9.

TCP Port 9 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.

TCP Port 9

Here is what we know about protocol TCP Port 9. If we do not have any information on port 9 in our database, a counter will be set for TCP port 9. After enough hits, we'll research this port and update the database.

If you have information on TCP port 9 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 9 will have the most accurate information.

PORT 9 - Information

Port Number:9
TCP / UDP:TCP
Delivery:Yes
Protocol / Name:discard
Port Description:Discard. Port equiv to /dev/null. Reads pkts, then discards them. Allows knowledge the host is alive and processing pkts. Used while trouble-shooting local stack's transmit ability (telnet to discard on remote host, knowing all transmitted keystrokes will just be discarded. no worry of corrupting host processes). No threat, but block on hosts and perimeter network devices as general rule.
Virus / Trojan:No

Side note: TCP port 9 uses the Transmission Control Protocol. TCP is one of the main protocols in TCP/IP networks. Whereas the IP protocol deals only with packets, TCP enables two hosts to establish a connection and exchange streams of data. TCP guarantees delivery of data and also guarantees that packets will be delivered on port 9 in the same order in which they were sent. Guaranteed communication over port 9 is the key difference between TCP and UDP. UDP port 9 would not have guaranteed communication in the same way as TCP.

TCP 9 - Disclaimer

We do our best to provide you with accurate information on PORT 9 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!