Abstract: A method of controlling Group establishment for an IP multimedia communication service facilitated over a communications network, wherein an established Group comprises a set of member Users each of which possesses a User Equipment and, at Group establishment, members' User Equipments are sent an invitation to join the group by a server of said communications network. The method comprises, within said communications network, defining for each of a set of Users of said service, a Group membership policy defining Groups that the User does or does not wish to join. Prior to Group establishment, for each User selected for possible inclusion in the Group, the Group membership policy for that User is used to determine whether or not the User may wish to be included. Invitations are sent only to those users for which it is determined that they may wish to be included in the Group.

Abstract: A method and apparatus for determining a list of members for a Group Push to Talk Session in a communications network. A Search Proxy function receives, from a requesting network node, a search request message. The search request message comprises at least one of an instruction to limit the maximum time for a search operation to take, an instruction to send search results in segmented blocks, an instruction to send search results in a predetermined format; and an instruction to perform a search according to a predetermined pattern. The Search Proxy function then performs a search for members with which to populate the list and sends the search results to a receiving node. In most cases, the receiving node is the requesting node.

Abstract: A method of controlling Group establishment for an IP multimedia communication service facilitated over a communications network, wherein an established Group comprises a set of member Users each of which possesses a User Equipment and, at Group establishment, members' group by a server of said communications network. The method comprises, within said communications network, defining for each of a set of Users of said service, a Group membership policy defining Groups that the User does or does not wish to join. Prior to Group establishment, for each User selected for possible inclusion in the Group, the Group membership policy for that User is used to determine whether or not the User may wish to be included. Invitations are sent only to CBUS those users for which it is determined that they Get may wish to be included in the Group.

Abstract: A method and apparatus for determining a list of members for a Group Push to Talk Session in a communications network. A Search Proxy function receives, from a requesting network node, a search request message. The search request message comprises at least one of an instruction to limit the maximum time for a search operation to take, an instruction to send search results in segmented blocks, an instruction to send search results in a predetermined format; and an instruction to perform a search according to a predetermined pattern. The Search Proxy function then performs a search for members with which to populate the list and sends the search results to a receiving node. In most cases, the receiving node is the requesting node.