Method for changing connection mode in base station, and base station therefor, and method for changing connection mode in user equipment, and user equipment thereof

A base station (BS) for changing a connection mode, the BS comprising,

• a transceiver, and
• a processor configured to control the transceiver, the processor configured to:
• control the transceiver to receive a connection re-establishment indication together with a connection release command for a user equipment (UE) from a core network;
• control the transceiver to transmit a connection release message including information on the connection re-establishment indication to the UE having a connection of a first mode;
• release the connection of the first mode from the UE while maintaining an uplink resource allocated to the UE;
• and
• control the transceiver to receive a connection request through the uplink resource without a random access procedure after releasing the connection of the first mode.

A method of changing a connection mode by a user equipment (UE), the method comprising:

• receiving a connection release message including information on a connection re-establishment indication from a network through a connection of a first mode;
• releasing the connection of the first mode while maintaining an uplink resource allocated to the UE;
• and
• transmitting a connection request to the network through the uplink resource without a random access procedure after releasing the connection of the first mode.

A user equipment (UE) for changing a connection mode, the UE comprising,

• a transceiver, and
• a processor configured to control the transceiver, the processor configured to:
• control the transceiver to receive a connection release message including information on a connection re-establishment indication from a network through a connection of a first mode;
• release the connection of the first mode while maintaining an uplink resource allocated to the UE;
• and
• control the transceiver to transmit a connection request to the network through the uplink resource without a random access procedure after releasing the connection of the first mode.