Port 17: QOTD

Port 17 is the Quote of the Day protocol, which returns a short text quote to any client that connects. It is a legacy service from the early internet with no practical modern use.

TCP/UDPLegacy protocolsUnencrypted by defaultIANA assigned
Port number17
ServiceQuote of the Day
ProtocolTCP/UDP
CategoryLegacy protocols
Default encryptionNo
Security note. Port 17 is not encrypted by default. Restrict it to trusted networks, or use an encrypted alternative where one exists, to avoid exposing credentials and data in transit.

Frequently asked questions

What is port 17 used for?

Port 17 is the Quote of the Day protocol, which returns a short text quote to any client that connects. It is a legacy service from the early internet with no practical modern use.

Is port 17 TCP or UDP?

Port 17 (QOTD) uses TCP/UDP.

Is port 17 secure?

Port 17 is not encrypted by default. Where possible, use an encrypted alternative or tunnel it over TLS or a VPN.

Should I open port 17 on my firewall?

Only if you specifically need QOTD. Expose it to the smallest set of trusted sources, and never open database or Windows-service ports to the whole internet.