Message generating arrangement

1. A message generating arrangement of a communication system, comprising:

a determining device configured to determine whether a first communication terminal of the communication system is enabled to participate, by means of only packet-switching network elements of the communication system in an absence of circuit-switching network elements in the first communication terminal, in a communication link in which a second communication terminal of the communication system is participating by means of circuit-switching network elements of the communication system; and

a message generating device configured to generate, if it has been determined that the first communication terminal is enabled to participate, by means of only the packet-switching network elements, in a communication link in which the second communication terminal is participating by means of the circuit-switching network elements, a message comprising the information that the first communication terminal supports that a packet-switched communication link and a circuit-switched communication link is enabled to exist in parallel between the first communication terminal and the second communication terminal.

2. The message generating arrangement according to claim 1 , wherein the message generating arrangement is arranged in the first communication terminal.

3. The message generating arrangement according to claim 1 , wherein the communication system has a communication network and the message generating device is a unit of the communication network.

4. The message generating arrangement according to claim 3 , wherein the message is generated by the message generating device as part of a protocol conversion from a signalling protocol which is used by the packet-switching network elements, to a signalling protocol which is used by the circuit-switching network elements.

5. The message generating arrangement according to claim 4 , wherein the signalling protocol used by the packet-switching network elements is Session Initiation Protocol (SIP).

6. The message generating arrangement according to claim 5 , wherein the signalling protocol used by the circuit-switching network elements is Signalling System Number 7 (SS7).

7. The message generating arrangement according to claim 3 , wherein the communication network is a mobile radio communication network.

8. The message generating arrangement according to claim 1 , wherein the first communication terminal is a mobile radio user terminal.

9. The message generating arrangement according to claim 1 , wherein the message generating device is configured to generate the message when the first communication terminal is registered with a network element of the communication system for utilizing packet-switched communication links.

10. The message generating arrangement according to claim 1 , wherein the determining device is configured to determine whether Voice Call Continuity Between Circuit Switched (CS) and Internet Protocol Multimedia Sub-System (IMS) (VCC) is supported for the first communication terminal.

11. The message generating arrangement according to claim 1 , wherein the message comprises the information that the first communication terminal supports Combining Circuit Switched (CS) calls and Internet Protocol Multimedia Sub-System (IMS) sessions (CSI).

12. A method for generating a message comprising:

determining whether a first communication terminal of a communication system is enabled to participate, by means of only packet-switching network elements of the communication system, in a communication link in which a second communication terminal of the communication system is participating by means of circuit-switching network elements of the communication system; and

if it has been determined that the first communication terminal is enabled to participate, by means of only the packet-switching network elements in an absence of circuit-switching network elements in the first communication terminal, in a communication link in which the second communication terminal is participating by means of the circuit-switching network elements, generating a message comprising the information that the first communication terminal supports that a packet-switched communication link and a circuit-switched communication link is enabled to exist in parallel between the first communication terminal and the second communication terminal.

13. A message generating arrangement of a communication system, comprising:

a determining device configured to determine whether a first communication terminal of the communication system is enabled to participate, by means of only the packet-switching domain of the communication system in an absence of circuit-switching network elements in the first communication terminal, in a communication link in which a second communication terminal of the communication system is participating by means of the circuit-switching domain of the communication system; and

a message generating device configured to generate, if it has been determined that the first communication terminal is enabled to participate, by means of only the packet-switching domain, in a communication link in which the second communication terminal is participating by means of the circuit-switching domain, a message comprising the information that the first communication terminal supports that a packet-switched communication link and a circuit-switched communication link is enabled to exist in parallel between the first communication terminal and the second communication terminal.

14. A communication terminal of a communication system, comprising:

a determining device configured to determine whether the communication terminal of the communication system is enabled to participate, by means of only packet-switching network elements of the communication system in an absence of circuit-switching network elements in the first communication terminal, in a communication link in which a further communication terminal of the communication system is participating by means of circuit-switching network elements of the communication system; and

a message generating device configured to generate, if it has been determined that the communication terminal is enabled to participate, by means of only the packet-switching network elements, in a communication link in which the further communication terminal is participating by means of the circuit-switching network elements, a message comprising the information that the communication terminal supports that a packet-switched communication link and a circuit-switched communication link is enabled to exist in parallel between the communication terminal and the further communication terminal.

15. A server unit of a communication system, comprising:

a determining device configured to determine whether a first communication terminal of the communication system is enabled to participate, by means of only packet-switching network elements of the communication system in an absence of circuit-switching network elements in the first communication terminal, in a communication link in which a second communication terminal of the communication system is participating by means of circuit-switching network elements of the communication system; and

a message generating device configured to generate, if it has been determined that the first communication terminal is enabled to participate, by means of only the packet-switching network elements, in a communication link in which the second communication terminal is participating by means of the circuit-switching network elements, a message comprising the information that the first communication terminal supports that a packet-switched communication link and a circuit-switched communication link is enabled to exist in parallel between the first communication terminal and the second communication terminal.

16. A message generating arrangement of a communication system, comprising:

a determining means for determining whether a first communication terminal of the communication system is enabled to participate, by means of only packet-switching network elements of the communication system in an absence of circuit-switching network elements in the first communication terminal, in a communication link in which a second communication terminal of the communication system is participating by means of circuit-switching network elements of the communication system; and

a message generating means for generating, if it has been determined that the first communication terminal is enabled to participate, by means of only the packet-switching network elements, in a communication link in which the second communication terminal is participating by means of the circuit-switching network elements, a message comprising the information that the first communication terminal supports that a packet-switched communication link and a circuit-switched communication link is enabled to exist in parallel between the first communication terminal and the second communication terminal.