Nominum, Inc. Cisco, Inc. Google The Special-Use Domain Names registration policy in RFC 6761 has been shown through experience to present unanticipated challenges. This memo presents a list, intended to be comprehensive, of the problems that have been identified. In addition it reviews the history of Domain Names and summarizes current IETF publications and some publications from other standards organizations relating to special- use domain names. [ Ed note: John Levine suggested we use 'Domain Names' instead of 'Internet Names'; this is the only change between -03 and -04. Please let us know which term you prefer. ]