A method of transferring ownership of a service group (SG) for a communication system comprising a server is disclosed. The service group comprises a first plurality of network elements. The method comprises receiving an owner transfer request that is transmitted from a first network element of the service group, wherein the first network element possesses the ownership of the service group; and selecting a second network element from the first plurality of network elements of the service group according to a selection procedure, to transfer the ownership of the service group from the first network element to the second network element; wherein the first network element and the second network element are managed by a first network gateway and a second network gateway of the communication system, respectively.