http://www.rfc-editor.org/rfc/rfc7605.txt
RFC 7605: Recommendations on Using Assigned Transport Port Numbers, J. Touch2015-08-01T23:00:00-00:00This document provides recommendations to designers of application and service protocols on how to use the transport protocol port number space and when to request a port assignment from IANA. It provides designer guidance to requesters or users of port numbers on how to interact with IANA using the processes defined in RFC 6335; thus, this document complements (but does not update) that document.