Method and apparatus of managing stored system information using validly timer when applying discontinuous reception mode in mobile communication system

A method for providing system information by a base station in a wireless communication system, the method comprising:

• generating a system information value tag to verify whether a stored system information in a user equipment (UE) remains valid;
• and
• transmitting, to the UE, system information including the system information value tag,
• wherein the stored system information is determined to be invalid after a predetermined time from a moment that the stored system information is confirmed as valid.

A user equipment (UE) for acquiring system information in a wireless communication system, the UE comprising:

• a transceiver;
• and
• a controller coupled with the transceiver and configured to control to:
• receive, from a base station, system information including a system information value tag,
• verify whether a stored system information remains valid by checking the system information value tag, and
• determine the stored system information to be invalid after a predetermined time from a moment that the stored system information was confirmed as valid.

A base station for providing system information in a wireless communication system, the base station comprising:

• a transceiver;
• and
• a controller coupled with the transceiver and configured to control to:
• generate a system information value tag to verify whether a stored system information in a user equipment (UE) remains valid, and
• transmit, to the UE, system information including the system information value tag,
• wherein the stored system information is determined to be invalid after a predetermined time from a moment that the stored system information was confirmed as valid.