Video telephony service method in mobile communication network

Abstract

The video telephony service method includes the step of the mobile communication system, which stores profile information, setting up a call between culling and called mobile communication terminals; the step of the mobile communication system transmitting the profile information of the calling mobile communication terminal to the called mobile communication terminal, as the calling mobile communication terminal transmits the profile information thereof to the mobile communication system; the step of the called mobile communication terminal consulting the profile information, and transmitting a response signal to the mobile communication system after establishing conditions for video telephony if it is determined that video telephony is possible for a received profile, and the mobile communication system transmitting the response signal to the calling mobile communication terminal; and the step of the mobile communication system establishing a communication path between the calling and called mobile communication terminals.

The invention claimed is: 
     
       1. A video telephony service method between mobile communication terminals, which can perform video telephony through a mobile communication system, in a mobile communication network, each of the mobile communication terminals storing profile information, the method comprising:
 the first step of the mobile communication system setting up a call between calling and called mobile communication terminals, as the calling mobile communication terminal attempts the call;   the second step of the mobile communication system transmitting the profile information of the calling mobile communication terminal to the called mobile communication terminal, as the calling mobile communication terminal transmits the profile information thereof to the mobile communication system;   the third step of the called mobile communication terminal consulting the profile information received from the calling mobile communication terminal, and transmitting a response signal to the mobile communication system after establishing conditions for video telephony if it is determined that video telephony is possible for a received profile, and the mobile communication system transmitting the response signal to the calling mobile communication terminal; and   the fourth step of the mobile communication system establishing a communication path between the calling and called mobile communication terminals.   
     
     
       2. A video telephony service method between mobile communication terminals, which can perform video telephony through a mobile communication system, in a mobile communication network, each of the mobile communication terminals storing profile information, the method comprising:
 the first step of the mobile communication system setting up a call between calling and called mobile communication terminals, as the calling mobile communication terminal attempts the call;   the second step of the mobile communication system transmitting the profile information of the calling mobile communication terminal to the called mobile communication terminal, as the calling mobile communication terminal transmits the profile information thereof to the mobile communication system;   the third step of performing a master/slave decision and response process, a terminal characteristic information exchange process, a multiplexing information exchange process, a logical channel generation process for voice transmission, and a logical channel generation process for video transmission, thus allowing negotiation to be performed between the calling mobile communication terminal and the called mobile communication terminal, if the called mobile communication terminal does not transmit a signal in response to the profile information to the calling mobile communication terminal within a designated period; and   the fourth step of the mobile communication system establishing a communication path between the calling and called mobile communication terminals.   
     
     
       3. A video telephony service method between mobile communication terminals, which can perform video telephony through a mobile communication system, in a mobile communication network, each of the mobile communication terminals storing profile information, the method comprising:
 the first step of the mobile communication system setting up a call between calling and called mobile communication terminals, as the calling mobile communication terminal attempts the call;   the second step of initiating a line connection and allocation process between the calling and called mobile communication terminals;   the third step of the mobile communication system transmitting the profile information of the calling mobile communication terminal to the called mobile communication terminal, as the calling mobile communication terminal transmits the profile information thereof to the mobile communication system;   the fourth step of the called mobile communication terminal consulting the profile information received from the calling mobile communication terminal, and transmitting a response signal to the mobile communication system after establishing conditions for video telephony if it is determined that video telephony is possible for a received profile, and the mobile communication system transmitting the response signal to the calling mobile communication terminal;   the fifth step of interrupting the line connection and allocation process initiated at the second step; and   the sixth step of the mobile communication system establishing a communication path between the calling and called mobile communication terminals.   
     
     
       4. The method according to any one of  claims 1  to  3 , wherein the profile information for the video telephony comprises voice codec information, video codec information, multiplexing information, and logical channel information. 
     
     
       5. The method according to any one of  claims 1  to  3 , wherein the video telephony is performed using a H.324M protocol, and the profile information for the video telephony is transmitted through a user input indication message of H.245 included in the H.324M protocol. 
     
     
       6. The method according to any one of  claims 1  to  3 , wherein, when the profile information for the video telephony is transmitted, an object identifier for identifying the profile information is transmitted along with the profile information. 
     
     
       7. The method according to  claim 6 , wherein the object identifier is composed of an object field and a data field, the object field having a mobile communication business name, a video telephony protocol name, a reason for message transmission and a type of profile, and the data field having detailed information of the profile. 
     
     
       8. The method according to any one of  claims 1  to  3 , wherein the profile information for video telephony comprises a plurality of pieces of profile information, each of which has a priority, and is stored in the mobile communication terminal, and the step of the mobile communication terminal transmitting the profile information is the step of transmitting profile information having a highest priority and then transmitting the plurality of pieces of profile information in descending order of priority when the mobile communication terminal that has received the profile information does not transmit a response signal. 
     
     
       9. The method according to  claim 1  or  2 , further comprising, after the second step and before the third step,
 as the called mobile communication terminal transmits the profile information to the mobile communication system, the fifth step of the mobile communication system transmitting the profile information of the called mobile communication terminal to the calling mobile communication terminal, and the sixth step of the calling and called mobile communication terminals preparing for the reception of data; 
 after the third step and before the fourth step, 
 the seventh step of the calling mobile communication terminal consulting the profile information received from the called mobile communication terminal, and transmitting a response signal to the mobile communication system after establishing conditions for video telephony if it is determined that video telephony is possible for a received profile, and the mobile communication system transmitting the response signal to the called mobile communication terminal. 
 
     
     
       10. The method according to  claim 3 , further comprising, after the third step and before the fourth step,
 as the called mobile communication terminal transmits the profile information to the mobile communication system, the sixth step of the mobile communication system transmitting profile information of the called mobile communication terminal to the calling mobile communication terminal, and the seventh step of the calling and called mobile communication terminals preparing for the reception of data;   after the third step and before the fourth step,   the eighth step of the calling mobile communication terminal consulting the profile information received from the called mobile communication terminal, and transmitting a response signal to the mobile communication system after establishing conditions for video telephony if it is determined that video telephony is possible for a received profile, and the mobile communication system transmitting the response signal to the called mobile communication terminal.   
     
     
       11. The method according to  claim 3 , wherein the line connection and allocation process of the second step comprises a master/slave decision and response process, a terminal characteristic information exchange process, a multiplexing information exchange process, a logical channel generation process for voice transmission, and a logical channel generation process for video transmission. 
     
     
       12. A video telephony service method between mobile communication terminals, which can perform video telephony through a mobile communication system, each of the mobile communication terminals storing profile information, the method comprising:
 the first step of a calling mobile communication terminal, which attempts to make a call, transmitting a first profile information thereof through the mobile communication system to a called mobile communication terminal without performing a master/slave decision, wherein the first profile information contains one or more codec types and contains a first logical channel information for setting up a logical communication path for video telephony;   the second step of the called mobile communication terminal consulting the first profile information, received from the calling mobile communication terminal, and determining from the one or more codec types in the first profile information if video telephony is possible with the first profile information;   the third step of the called mobile communication terminal transmitting a first response signal through the mobile communication system to the calling mobile communication terminal upon concluding that video telephony is possible with the first profile information; and   the fourth step of establishing a communication path, based on the first logical channel information contained in the first profile information through the mobile communication system between the calling mobile communication terminal and the called mobile communication terminal.   
     
     
       13. The method according to claim 12, the first profile information comprises a plurality of video codec types transmitted together, and the response signal includes profile information selected among the plurality of video codec types. 
     
     
       14. The method according to claim 12, the first profile information comprises a plurality of video codec types, each of which has a priority, and the first step comprises transmitting the plurality of video codec types in descending order of priority when the called terminal does not transmit the response signal. 
     
     
       15. The method according to claim 12, further comprising:
 after the first step, the fifth step of the called mobile communication terminal transmitting a second profile information thereof through the mobile communication system to the calling mobile communication terminal,   wherein the second profile information contains one or more codec types of the called mobile communication terminal and a second logical channel information;   before the fourth step, the sixth step of the calling mobile communication terminal transmitting a second response signal through the mobile communication system to the called mobile communication terminal upon concluding that video telephony is possible with the second profile information.   
     
     
       16. The method according to claim 12, wherein the mobile communication system is an Internet Protocol (IP) network. 
     
     
       17. A video telephony service method between mobile communication terminals, which can perform video telephony through a mobile communication system, each of the mobile communication terminals storing profile information, the method performed by a called mobile communication terminal comprising:
 the first step of receiving a first profile information of a calling mobile communication terminal, which attempts to make a call, through the mobile communication system without master/slave decision, wherein the first profile information contains one or more codec types and a first logical channel information for setting up a logical communication path for video telephony;   the second step of consulting the first profile information, received from the calling mobile communication terminal, and determining from the one or more codec types in the first profile information if video telephony is possible with the first profile information;   the third step of transmitting a first response signal through the mobile communication system to the calling mobile communication terminal upon concluding that video telephony is possible with the first profile information; and   the fourth step of establishing the communication path, based on the first logical channel information contained in the first profile information with the calling mobile communication terminal through the mobile communication system.   
     
     
       18. The method according to claim 17, further comprising:
 after the first step, the fifth step of transmitting a second profile information thereof through the mobile communication system to the calling mobile communication terminal,   wherein the second profile information contains one or more codec types of the called mobile communication terminal and a second logical channel information;   before the fourth step, the sixth step of receiving a second response signal from the calling mobile communication terminal through the mobile communication system, wherein the second response signal indicates that video telephony is possible with the second profile information.