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

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.

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.

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.