Communication Management System, Communication System, Computer-Readable Recording Medium, and Maintenance System

1. An apparatus comprising: a memory that stores first address information of a first communication terminal and second address information of a second communication terminal; a receiver that receives first start request information to start communication between the first communication terminal and the second communication terminal using a first communication method or second start request information to start communication between the first communication terminal and a third communication terminal, from the first communication terminal, the third communication terminal transmitting and receiving communication data using a second communication method different from the first communication method; and a transmitter that: transmits, to a relay device, first session request information including at least the first address information of the first communication terminal and the second address information of the second communication terminal to establish a session for transmitting and receiving communication data based on the first communication method between the first communication terminal and the second communication terminal through the relay device when the receiver receives the first start request information, and transmits, to the relay device, second session request information including at least the first address information of the first communication terminal and third address information of the third communication terminal to transmit and receive communication data between the first communication terminal and the third communication terminal through a conversion system that performs mutual conversion between the first communication method and the second communication method as well as through the relay device to which the transmitter transmits the first session request information, when the receiver receives the second start request information, wherein the second session request information is used in order to allow the relay device to instruct the conversion system to start the session.

2. The apparatus according to claim 1 , further comprising: processing circuitry that extracts address information to be transmitted to the relay device, based on the received first start request information or the received second start request information, wherein the memory stores identification information for identifying the third communication terminal, another instance of address information of the conversion system, and the third address information of the third communication terminal in association with one another, the receiver receives the identification information of the third communication terminal when receiving the second start request information from the first communication terminal, and the processing circuitry searches the memory based on the received identification information of the third communication terminal and extracts the another instance of address information of the conversion system and the third address information of the third communication terminal.

3. The apparatus according to claim 2 , wherein the processing circuitry determines whether a communication method used by each communication terminal is a predetermined communication method, the memory stores communication method information representing the communication method used by each communication terminal in association with identification information of each communication terminal, the processing circuitry searches the memory based on the received identification information of the third communication terminal, and extracts a corresponding communication method information, the processing circuitry determines whether the communication method represented by the extracted corresponding communication method information is the communication method used by the first communication terminal, and when the processing circuitry determines that the communication method represented by the extracted corresponding communication method information is not the communication method used by the first communication terminal, the processing circuitry searches the memory based on the identification information of the third communication terminal received by the receiver, and extracts the another instance of address information of the conversion system and the second address information of the second communication terminal.

4. The apparatus according to claim 3 , wherein the communication method is represented by a call control method for establishing or disconnecting a connection with a destination of a communication and a coding method for converting the communication data into IP packets, and when the communication method represented by the corresponding communication method information extracted by the processing circuitry is different from the communication method used by the first communication terminal in at least one of the call control method and the coding method, the processing circuitry determines that the communication method represented by the corresponding communication method information extracted by the processing circuitry is not the communication method used by the first communication terminal.

5. The apparatus according to claim 1 , wherein the memory stores address information representing a destination of the first communication terminal in association with identification information for identifying the first communication terminal, the receiver receives the identification information of the first communication terminal from the first communication terminal when receiving the first start request information, and the processing circuitry searches the memory based on the received identification information of the first communication terminal, and extracts a corresponding destination information of the first communication terminal.

6. The apparatus according to claim 1 , wherein the first communication method and the second communication method include at least a session control protocol and a video coding method, and the first communication method and the second communication method differ in at least one of the session control protocol and the video coding method.

7. The apparatus according to claim 6 , wherein the video coding method for the first communication method is H.264/Scalable Video Coding (SVC), and the video coding method for the second communication method is H.264/Advanced Video Coding (AVC).

8. The apparatus according to claim 1 , wherein the first communication method and the second communication method differ in both of a session control protocol and a video coding method.

9. The apparatus according to claim 1 , wherein the second session request information further includes another instance of address information of the conversion system.

10. The apparatus according to claim 1 , wherein the second session request information further includes another instance of address information of the conversion system, and the first session request information does not include the another instance of address information of the conversion system.

11. A method comprising: storing, using a memory, first address information of a first communication terminal and second address information of a second communication terminal; receiving, using a receiver, first start request information to start communication between the first communication terminal and the second communication terminal using a first communication method or second start request information to start communication between the first communication terminal and a third communication terminal, from the first communication terminal, the third communication terminal transmitting and receiving communication data using a second communication method different from the first communication method; transmitting, using a transmitter to a relay device, first session request information including at least the first address information of the first communication terminal and the second address information of the second communication terminal to establish a session for transmitting and receiving communication data based on the first communication method between the first communication terminal and the second communication terminal through the relay device when the receiver receives the first start request information; and transmitting, using the transmitter to the relay device, second session request information including at least the first address information of the first communication terminal and third address information of the third communication terminal to transmit and receive communication data between the first communication terminal and the third communication terminal through a conversion system that performs mutual conversion between the first communication method and the second communication method as well as through the relay device to which the transmitter transmits the first session request information, when the receiver receives the second start request information, wherein the second session request information is used in order to allow the relay device to instruct the conversion system to start the session.

12. The method according to claim 11 , further comprising: extracting, using processing circuitry, address information to be transmitted to the relay device, based on the received first start request information or the received second start request information; storing identification information for identifying the third communication terminal, another instance of address information of the conversion system, and the third address information of the third communication terminal in association with one another; receiving, using the receiver, the identification information of the third communication terminal when receiving the second start request information from the first communication terminal; and searching, using the processing circuitry, the memory based on the received identification information of the third communication terminal, and extracting the another instance of address information of the conversion system and the third address information of the third communication terminal.

13. The method according to claim 12 , further comprising: determining, using the processing circuitry, whether a communication method used by each communication terminal is a predetermined communication method; storing communication method information representing the communication method used by each communication terminal in association with identification information of each communication terminal; searching, using the processing circuitry, the memory based on the received identification information of the third communication terminal, and extracting a corresponding communication method information; determining, using the processing circuitry, whether the communication method represented by the extracted corresponding communication method information is the communication method used by the first communication terminal; and when the processing circuitry determines that the communication method represented by the extracted corresponding communication method information is not the communication method used by the first communication terminal, searching, using the processing circuitry, the memory based on the identification information of the third communication terminal received by the receiver, and extracting the another instance of address information of the conversion system and the second address information of the second communication terminal.

14. The method according to claim 13 , wherein the communication method is represented by a call control method for establishing or disconnecting a connection with a destination of a communication and a coding method for converting the communication data into IP packets, the method further comprising: when the communication method represented by the corresponding communication method information extracted by the processing circuitry is different from the communication method used by the first communication terminal in at least one of the call control method and the coding method, determining, using the processing circuitry, that the communication method represented by the corresponding communication method information extracted by the processing circuitry is not the communication method used by the first communication terminal.

15. The method according to claim 11 , further comprising: storing address information representing a destination of the first communication terminal in association with identification information for identifying the first communication terminal; receiving, using the receiver, the identification information of the first communication terminal from the first communication terminal when receiving the first start request information; and searching, using the processing circuitry, the memory based on the received identification information of the first communication terminal, and extracting a corresponding destination information of the first communication terminal.

16. The method according to claim 11 , wherein the first communication method and the second communication method include at least a session control protocol and a video coding method, and the first communication method and the second communication method differ in at least one of the session control protocol and the video coding method.

17. The method according to claim 16 , wherein the video coding method for the first communication method is H.264/Scalable Video Coding (SVC), and the video coding method for the second communication method is H.264/Advanced Video Coding (AVC).

18. The method according to claim 11 , wherein the first communication method and the second communication method differ in both of a session control protocol and a video coding method.

19. The method according to claim 11 , wherein the second session request information further includes another instance of address information of the conversion system.

20. A non-transitory computer-readable storage medium storing computer-readable instructions that, when executed by a computer, cause the computer to execute a method comprising: storing first address information of a first communication terminal and second address information of a second communication terminal; receiving first start request information to start communication between the first communication terminal and the second communication terminal using a first communication method or second start request information to start communication between the first communication terminal and a third communication terminal, from the first communication terminal, the third communication terminal transmitting and receiving communication data using a second communication method different from the first communication method; transmitting, to a relay device, first session request information including at least the first address information of the first communication terminal and the second address information of the second communication terminal to establish a session for transmitting and receiving communication data based on the first communication method between the first communication terminal and the second communication terminal through the relay device when a receiver receives the first start request information; and transmitting, to the relay device, second session request information including at least the first address information of the first communication terminal and third address information of the third communication terminal to transmit and receive communication data between the first communication terminal and the third communication terminal through a conversion system that performs mutual conversion between the first communication method and the second communication method as well as through the relay device to which the transmitter transmits the first session request information, when the receiver receives the second start request information, wherein the second session request information is used in order to allow the relay device to instruct the conversion system to start the session.

21. The non-transitory computer-readable storage medium according to claim 20 , further comprising: extracting address information to be transmitted to the relay device, based on the received first start request information or the received second start request information; storing identification information for identifying the third communication terminal, another instance of address information of the conversion system, and the third address information of the third communication terminal in association with one another; receiving the identification information of the third communication terminal when receiving the second start request information from the first communication terminal; and searching a memory based on the received identification information of the third communication terminal, and extracting the another instance of address information of the conversion system and the third address information of the third communication terminal.

22. The non-transitory computer-readable storage medium according to claim 21 , further comprising: determining whether a communication method used by each communication terminal is a predetermined communication method; storing communication method information representing the communication method used by each communication terminal in association with identification information of each communication terminal; searching the memory based on the received identification information of the third communication terminal, and extracting a corresponding communication method information; determining whether the communication method represented by the extracted corresponding communication method information is the communication method used by the first communication terminal; and when the communication method represented by the extracted corresponding communication method information is determined not to be the communication method used by the first communication terminal, searching the memory based on the identification information of the third communication terminal received by the receiver, and extracting the another instance of address information of the conversion system and the second address information of the second communication terminal.

23. The non-transitory computer-readable storage medium according to claim 22 , wherein the communication method is represented by a call control method for establishing or disconnecting a connection with a destination of a communication and a coding method for converting the communication data into IP packets, further comprising: when the communication method represented by the extracted corresponding communication method information is different from the communication method used by the first communication terminal in at least one of the call control method and the coding method, determining that the communication method represented by the extracted corresponding communication method information is not the communication method used by the first communication terminal.

24. The non-transitory computer-readable storage medium according to claim 20 , further comprising: storing address information representing a destination of the first communication terminal in association with identification information for identifying the first communication terminal; receiving the identification information of the first communication terminal from the first communication terminal when receiving the first start request information; and searching the memory based on the received identification information of the first communication terminal, and extracting a corresponding destination information of the first communication terminal.

25. The non-transitory computer-readable storage medium according to claim 20 , wherein the first communication method and the second communication method include at least a session control protocol and a video coding method, and the first communication method and the second communication method differ in at least one of the session control protocol and the video coding method.

26. The non-transitory computer-readable storage medium according to claim 25 , wherein the video coding method for the first communication method is H.264/Scalable Video Coding (SVC), and the video coding method for the second communication method is H.264/Advanced Video Coding (AVC).

27. The non-transitory computer-readable storage medium according to claim 20 , wherein the first communication method and the second communication method differ in both of a session control protocol and a video coding method.

28. The non-transitory computer-readable storage medium according to claim 20 , wherein the second session request information further includes another instance of address information of the conversion system.

29. A system comprising: a first communication terminal; a second communication terminal that transmits and receives communication data with the first communication terminal using a first communication method; a memory that stores first address information of the first communication terminal and second address information of the second communication terminal; a receiver that receives first start request information to start communication between the first communication terminal and the second communication terminal using the first communication method or second start request information to start communication between the first communication terminal and a third communication terminal, from the first communication terminal, the third communication terminal transmitting and receiving communication data using a second communication method different from the first communication method; and a transmitter that: transmits, to a relay device, first session request information including at least the first address information of the first communication terminal and the second address information of the second communication terminal to establish a session for transmitting and receiving communication data based on the first communication method between the first communication terminal and the second communication terminal through the relay device when the receiver receives the first start request information, and transmits, to the relay device, second session request information including at least the first address information of the first communication terminal and third address information of the third communication terminal to transmit and receive communication data between the first communication terminal and the third communication terminal through a conversion system that performs mutual conversion between the first communication method and the second communication method as well as through the relay device to which the transmitter transmits the first session request information, when the receiver receives the second start request information, wherein the second session request information is used in order to allow the relay device to instruct the conversion system to start the session.