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This is a tech blog about security related topics such as offensive security, public cloud security and capture the flag writeups. I hope you will find some valuable information. Got feedback or want to get in touch? Reach me via twitter
Network Working Group J. Postel
Request for Comments: 863 ISI
May 1983
Discard Protocol
This RFC specifies a standard for the ARPA Internet community. Hosts on
the ARPA Internet that choose to implement a Discard Protocol are
expected to adopt and implement this standard.
A useful debugging and measurement tool is a discard service. A discard
service simply throws away any data it receives.
TCP Based Discard Service
One discard service is defined as a connection based application on
TCP. A server listens for TCP connections on TCP port 9. Once a
connection is established any data received is thrown away. No
response is sent. This continues until the calling user terminates
the connection.
UDP Based Discard Service
Another discard service is defined as a datagram based application on
UDP. A server listens for UDP datagrams on UDP port 9. When a
datagram is received, it is thrown away. No response is sent.