Method and apparatus for transmitting and receiving data using plurality of carriers in mobile communication system

1. A method by a terminal in a communication system, the method comprising:

receiving, from a master base station, a first message including first configuration information for a first cell group associated with the master base station, wherein the first configuration information for the first cell group includes configuration information for first medium access control (MAC);

configuring a first MAC entity for the first cell group based on the configuration information for the first MAC;

receiving, from the master base station, a second message including second configuration information for a secondary cell group associated with a secondary base station, wherein the second configuration information for the secondary cell group includes configuration information for second MAC; arid

configuring a second MAC entity for the secondary cell group based on the configuration information for the second MAC.

2. The method of claim 1 , wherein the second configuration information for the secondary cell group includes configuration information for a bearer,

wherein the configuration information for the bearer includes at least one of an identification of the bearer, configuration information for radio link control (RLC), or configuration information for a logical channel, and

wherein the configuring of the second MAC entity for the secondary cell group includes reconfiguring (1) an RLC entity for the first cell group associated with the master base station to an RLC entity for the secondary cell group and (2) a logical channel for the first cell group to a logical channel for the secondary cell group based on the configuration information of the bearer.

3. The method of claim 1 , wherein the second configuration information for the secondary cell group is generated by the secondary base station.

4. The method of claim 1 , wherein the second message includes a radio resource control (RRC) ConnectionReconfiguration message.

5. A terminal in a communication system, the terminal comprising:

a transceiver; and

a controller configured to:

control the transceiver to receive, from a master base station, a first message including first configuration information for a first cell group associated with the master base station, wherein the first configuration information for the first cell group includes configuration information for first medium access control (MAC),

configure a first MAC entity for the first cell group based on the configuration information for the first MAC,

control the transceiver to receive, from a master base station, a second message including second configuration information for a secondary cell group associated with a secondary base station, wherein the second configuration information for the secondary cell group includes configuration information for second MAC, and

configure a second MAC entity for the secondary cell group based on the configuration information for the second MAC.

6. The terminal of claim 5 , wherein the second configuration information for the secondary cell group includes configuration information for a bearer,

wherein the configuration information for the bearer includes at least one of an identification of the bearer, configuration information for radio link control (RLC), or configuration information for a logical channel, and

wherein the controller is configured to reconfigure (1) an RLC entity for the first cell group associated with the master base station to an RLC entity for the secondary cell group and (2) a logical channel for the first cell group to a logical channel for the secondary cell group based on the configuration information of the bearer.

7. The terminal of claim 5 , wherein the second configuration information for the secondary cell group is generated by the secondary base station.

8. The terminal of claim 5 , wherein the second message includes a radio resource control (RRC) ConnectionReconfiguration message.

9. A method by a master base station in a communication system, the method comprising:

transmitting, to a terminal, a first message including first configuration information for a first cell group associated with the master base station, wherein the first configuration information for the first cell group includes configuration information for first medium access control (MAC);

determining to add at least one cell associated with a secondary base station;

transmitting, to the secondary base station, a request for information required for the addition;

receiving, from the secondary base station, second configuration information for a secondary cell group associated with the secondary base station, in response to the request; and

transmitting, to the terminal, a second message including second configuration information for a secondary cell group associated with a secondary base station, wherein the second configuration information for the secondary cell group includes configuration information for second MAC.

10. The method of claim 9 , wherein the configuration information for second MAC is used by the terminal to generate a MAC entity for the secondary cell group based on the configuration information for the second MAC.

11. The method of claim 9 , wherein the second configuration information for the secondary cell group includes configuration information for a bearer,

wherein the configuration information for the bearer includes at least one of an identification of the bearer, configuration information for radio link control (RLC), or configuration information for a logical channel, and

wherein the configuration information of the bearer is used by the terminal to reconfigure (1) an RLC entity for the first cell group associated with the master base station to an RLC entity for the secondary cell group and (2) a logical channel for the first cell group to a logical channel for the secondary cell group.

12. The method of claim 9 , wherein the second configuration information for the secondary cell group is generated by the secondary base station.

13. The method of claim 9 , wherein the second message includes a radio resource control (RRC) ConnectionReconfiguration message.

14. The method of claim 9 , wherein the determining to add at least one cell comprises:

receiving, from the terminal, a measurement report; and

determining to add at least one cell associated with the secondary base station based on the received measurement report.

15. A master base station in a communication system, the master base station comprising:

a transceiver; and

a controller configured to:

control the transceiver to transmit, to a terminal, a first message including first configuration information for a first cell group associated with the master base station, wherein the first configuration information for the first cell group includes configuration information for first medium access control (MAC);

determine to add at least one cell associated with a secondary base station;

control the transceiver to transmit, to the secondary base station, a request for information required for the addition;

control the transceiver to receive, from the secondary base station, second configuration information for a secondary cell group associated with the secondary base station, in response to the request; and

control the transceiver to transmit, to the terminal, a second message including second configuration information for a secondary cell group associated with a secondary base station, wherein the second configuration information for the secondary cell group includes configuration information for second MAC.

16. The master base station of claim 15 , wherein the configuration information for second MAC is used by the terminal to generate a MAC entity for the secondary cell group based on the configuration information for the second MAC.

17. The master base station of claim 15 , wherein the second configuration information for the secondary cell group includes configuration information for a bearer,

wherein the configuration information for the bearer includes at least one of an identification of the bearer, configuration information for radio link control (RLC), or configuration information for a logical channel, and

wherein the configuration information of the bearer is used by the terminal to reconfigure (1) an RLC entity for the first cell group associated with the master base station to an RLC entity for the secondary cell group and (2) a logical channel for the first cell group to a logical channel for the secondary cell group.

18. The master base station of claim 15 , wherein the second configuration information for the secondary cell group is generated by the secondary base station.

19. The master base station of claim 15 , wherein the second message includes a radio resource control (RRC) ConnectionReconfiguration message.

20. The master base station of claim 15 , wherein the controller is further configured to:

control the transceiver to receive, from the terminal, a measurement report; and

determine to add at least one cell associated with the secondary base station based on the received measurement report.