Patent ID: 8213900

Claim:
A method for establishing at least one of IP-based telephony or video telephony based on a session initiation protocol (SIP) in heterogeneous networks, wherein a control module in a central connecting unit is configured to set up a connection between the network nodes, the method comprising: requesting a data link to one or more network nodes from the central connecting unit in an IP network, at least one network node being an IP network node and at least some of the network nodes being registered with a registration module in the central connecting unit; requesting an identity of the IP network node via a registration module; transmitting an International Mobile Subscriber Identity (IMSI) stored on a Subscriber Identity Module (SIM) card of the IP network node to the registration module; storing the received IMSI in a user database of the registration module; complementing an IP data channel to form signal and data channels of a GSM network via a signaling gateway module; generating the necessary SS7/MAP functions for authenticating the IP network node based on the complemented IP data channel having GSM data; authenticating the IP network node in that the registration module uses the user database and the signaling gateway module on the basis of the IMSI of the SIM card of the IP network node in at least one of a Home Location Register (HLR), Visited Location Register (VLR), Authentication Center (AuC), or functionally equivalent database; receiving an entry in the user database of the registration module upon successful authentication; and setting up a data link from the IP network node to the at least some of the network nodes via the control module of the central connecting unit, wherein the authenticating further includes taking a result of the authentication as a basis for at least one of granting a service authorization to use the central connecting unit or performing billing for a demanded service using a billing module.