The present document defines the methodology for discovering an Authoritative FQDN for a radio service@ including discovery using DNS queries to radiodns.org@ a root domain name server operated by RadioDNS. The present document also defines the construction of a unique ServiceIdentifier parameter and bearerURI for a radio service. NOTE: Specifications for applications built upon the RadioDNS methodology can be found at http:/ adiodns.org/developers/documentation/ .