Editing QOTD

{{Short description|Internet protocol that provides the quote  of the day}}
{{IPstack}}
The '''Quote of the Day''' ('''QOTD''') service is a member of the [[Internet protocol suite]], defined in 1983 in RFC 865 by [[Jon Postel]]. As indicated there, the QOTD concept predated the specification, when QOTD was used by mainframe sysadmins to broadcast a daily quote on request by a user. It was then formally codified both for prior purposes as well as for testing and measurement purposes.

A host may connect to a server that supports the QOTD protocol, on either [[Transmission Control Protocol|TCP]] or [[User Datagram Protocol|UDP]] port 17.<ref>{{cite book |last1=Graham |first1=Buck |title=TCP/IP Addressing |date=1997 |publisher=Academic Press |isbn=0-12-294630-8 |page=[https://archive.org/details/tcpipaddressingd0000grah/page/26 26] |url-access=registration |url=https://archive.org/details/tcpipaddressingd0000grah/page/26 }}</ref> To keep the quotes at a reasonable length, RFC 865 specifies a maximum of 512 octets for the quote.

Although some sources<ref name="secspace" /> indicate that the QOTD service is rarely enabled, and is in any case often [[Firewall (computing)|firewalled]] to avoid [[Denial-of-service attack|denial-of-service]] attacks,<ref name="secspace">{{cite web| url=http://www.securityspace.com/smysecure/catid.html?id=10198|title=Check for presence of qotd|last=Perrin|first=Mathieu|date=1999|publisher=security space|access-date=23 August 2015}}</ref> interest continues in the pre-existing purpose of serving quotes as can be seen with web engine searches.

Current testing and measurement of [[IP network]]s is more commonly done with [[Ping (networking utility)|ping]] and [[traceroute]], which are more robust adaptations of the [[echo protocol]] (RFC 862), which predated the attempt at QOTD standardization.

==References==
{{Reflist}}

{{Internet-stub}}
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[[Category:Internet protocols]]
[[Category:Application layer protocols]]