Method for communication between a switched circuit communication network and at least two VoIP network domains (DA, DB, DC) each comprising a packet-based signaling controller (GKA, GKB, GKC), wherein a gateway device connected between the switched circuit communication network and the VoIP network domains (DA, DB, DC) transmits in each case a registration request message by means of a query device to the signaling controllers (GKA, GKB, GKC), wherein a) the one gateway device has a connection-oriented interface for the connection to the switched circuit communication network as well as packet-oriented interfaces for the connection of the VoIP network domains (DA, DB, DC), b) wherein the packet-oriented interfaces are implemented by different Internet protocol-based ports, c) wherein the query device is coupled to the packet-oriented interfaces and determines transport addresses of the accessible signaling controllers (GKA, GKB, GKC), wherein each transport address comprises the Internet protocol address of the signaling controller in question as well as the port number of the service to be used, d) wherein the one gateway device is implemented by means of a gateway - either according to the H. 323 recommendation - or alternatively according to the SIP standard, which is reconfigured in such a manner that the gateway device is registered simultaneously in the at least two VoIP network domains (DA, DB, DC) as VoIP end point, e) wherein the one registered gateway device e1) receives, from the switched circuit communication network, a connection-oriented connection setup message (SETUP) with target address information identifying a communication target, e2) evaluates the received target address information and e3) depending on the evaluation, makes a selection relating to the further connection setup from the VoIP network domains (DA, DB, DC) and/or the signaling controllers (GKA, GKB, GKC). a) the one gateway device has a connection-oriented interface for the connection to the switched circuit communication network as well as packet-oriented interfaces for the connection of the VoIP network domains (DA, DB, DC), b) wherein the packet-oriented interfaces are implemented by different Internet protocol-based ports, c) wherein the query device is coupled to the packet-oriented interfaces and determines transport addresses of the accessible signaling controllers (GKA, GKB, GKC), wherein each transport address comprises the Internet protocol address of the signaling controller in question as well as the port number of the service to be used, d) wherein the one gateway device is implemented by means of a gateway - either according to the H. 323 recommendation - or alternatively according to the SIP standard, which is reconfigured in such a manner that the gateway device is registered simultaneously in the at least two VoIP network domains (DA, DB, DC) as VoIP end point, - either according to the H. 323 recommendation - or alternatively according to the SIP standard, e) wherein the one registered gateway device e1) receives, from the switched circuit communication network, a connection-oriented connection setup message (SETUP) with target address information identifying a communication target, e2) evaluates the received target address information and e3) depending on the evaluation, makes a selection relating to the further connection setup from the VoIP network domains (DA, DB, DC) and/or the signaling controllers (GKA, GKB, GKC). e1) receives, from the switched circuit communication network, a connection-oriented connection setup message (SETUP) with target address information identifying a communication target, e2) evaluates the received target address information and e3) depending on the evaluation, makes a selection relating to the further connection setup from the VoIP network domains (DA, DB, DC) and/or the signaling controllers (GKA, GKB, GKC).