IANA administers
Internet multicast addresses. Potential conflicts with Internet multicast address assignments can be avoided by using
GLOP addressing (
AS required) or
administratively scoped addresses. Such addresses can be safely used on a network connected to the Internet without fear of conflict with multicast sources originating on the Internet. Administratively scoped addresses are roughly analogous to the unicast address space for
private internets. Site-local multicast addresses are of the form
239.255.x.y, but can grow down to
239.252.x.y if needed. Organization-local multicast addresses are of the form
239.192-251.x.y, but can grow down to
239.x.y.z if needed.