Call setup from a circuit switched network to a terminal residing within a packet switched network

摘要

A user with a terminal residing in a Circuit Switched (CS) telecommunication network calls a party having a terminal residing at a Packet Switched (PS) telecommunication network, the CS and PS networks connected to each other by gateway entity. The party to be called at the PS network is addressed by means of a Session Initiation Protocol Universal Resource Identifier (SIP-URI). The call setup is performed in a two step process. In a first step, the terminal sends a the SIP-URI in a message together with the address of this terminal to a network entity which stores said message. In a second step, the terminal calls the network entity, wherein the network entity selects the stored SIP-URI and resolves the SIP-URI into an address of the terminal at the PS network and instructs the gateway entity to connect the calling terminal to the terminal.

主权项

1. A method for performing a call setup from a first terminal residing in a Circuit Switched telecommunication network to a second terminal residing in a Packet Switched telecommunication network, the Circuit Switched network and the Packet switched network being communicatively connected to each other, the method comprising the steps of:
receiving a message, the message being triggered by the first terminal, and comprising an address of the first terminal and an address of a party to be called at the second terminal; storing the message in a database; receiving a call setup request, the call setup request being triggered by the first terminal after having triggered the message; selecting from the database the stored message comprising the address of the first terminal, which address corresponds to the address comprised by the call setup request; retrieving the address of the party to be called from the selected stored message, and resolving the address of the party to be called into an address of the second terminal; setting up the call between the first terminal and the second terminal identified by the resolved address of the second terminal, and connecting the call.