Method and system for multicast broadcasting towards a roaming terminal according to the location thereof

A system of multicast broadcasting to a roaming terminal according to a location of an IP network connection of the roaming terminal, following a routine connection of the roaming terminal to at least one of a site affiliated or not affiliated to an original site and an original organization to which the roaming terminal is attached and transmission of a signaling message from the roaming terminal to the original site, the system comprising:

• on said original site,
• means of discriminating the location of the roaming terminal with respect to the original site, or the original organization, from the signaling message, and
• means of transmitting to the roaming terminal a location discriminating information item;
• and
• on the roaming terminal,
• means for determining from the said location discriminating item whether the roaming terminal is outside its original site or its original organization;
• means for determining whether an access request from the roaming terminal to access a group multicast broadcast relates to a group multicast broadcast intended for and local to the original site, or to the original organization, of said roaming terminal, by discriminating the address of the access request to determine whether the address is a global address, an address local to the organization or an address local to the original site;
• means of replacing the access request with a request to access an extended multicast broadcast allowing access to the local multicast broadcast, when
• the location discriminating information item designates a connection of the roaming terminal outside the original site, or the original organization, and
• the means for determining whether an access request from the roaming terminal to access a group multicast broadcast relates to a group multicast broadcast intended for and local to the original site, or to the original organization, of the roaming terminal determines that the request to access a group multicast broadcast is intended for the original site and relates to a multicast broadcast local to the original site, or to the original organization, of said roaming terminal, and
• means of transmitting to the original site said request to access the extended multicast broadcast, or alternatively said access request to access a group multicast broadcast.

A roaming terminal, comprising:

• communication means configured for setting up a connection with an original site to which said roaming terminal is attached,
• synchronization means configured for transmitting a synchronization message to the original site,
• means of receiving a location discriminating information item sent in return by the original site, the means of receiving being connected to means of accessing a group multicast broadcast local to the original site;
• and
• means for determining whether an access request from the roaming terminal to access a group multicast broadcast relates to a group multicast broadcast intended for and local to the original site, or to the original organization, of said roaming terminal, by discriminating the address of the access request to determine whether the address is a global address, an address local to the organization or an address local to the original site,
• wherein the means of accessing a group multicast broadcast local to the original site is configured for converting a request to access a local multicast broadcast into a request to access an extended multicast broadcast enabling access to the local multicast broadcast when
• 1 the location discriminating information item designates a connection of the roaming terminal outside the original site;
• and
• 2 the means for determining whether an access request from the roaming terminal to access a group multicast broadcast relates to a group multicast broadcast intended for and local to the original site, or to the original organization, of said roaming terminal determines that the request to access a group multicast broadcast is intended for the original site and relates to a multicast broadcast local to the original site, or to the original organization, of said roaming terminal,
• the terminal further comprising means of transmitting to the original site said request to access the extended multicast broadcast, or alternatively said access request to access a group multicast broadcast.