A method for broadcasting extensive multicast from a multicast exchange having a first address of a site of origin. A query of extensive multicast broadcasting containing the first address and an identification code of a mobile terminal is transmitted from the mobile terminal toward the site. A message offering access containing a second global multicast broadcasting address, whose source is situated in the site of origin, is transmitted from the site toward the mobile terminal. A message accepting access is transmitted from the mobile terminal toward the site upon the broadcasting to the second address. Information to be diffused is transferred from the first to the second address, and global multicast is transmitted by broadcasting to the second address. The mobile terminal receives, at the distinct site, the information diffused under the first address diffused under the second address.