Assigned Port Numbers

This table lists the well-known port numbers in the range 0 to 1023, assigned and controlled by ICANN. Ports not mentioned in this list are currently unassigned.

Keyword Decimal Description
  0/tcp Reserved
  0/udp Reserved
tcpmux 1/tcp TCP Port Service Multiplexer
tcpmux 1/udp TCP Port Service Multiplexer
compressnet 2/tcp Management Utility
compressnet 2/udp Management Utility
compressnet 3/tcp Compression Process
compressnet 3/udp Compression Process
rje 5/tcp Remote Job Entry
rje 5/udp Remote Job Entry
echo 7/tcp Echo
echo 7/udp Echo
discard 9/tcp Discard
discard 9/udp Discard
systat 11/tcp Active Users
systat 11/udp Active Users
daytime 13/tcp Daytime
daytime 13/udp Daytime
qotd 17/tcp Quote of the ...

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