Communication system, user equipment, base station, mobility management device, and gateway device

Abstract

In a communication system, an eNB and a UE transmit and receive a UE monitoring message for confirming the state of the UE in a predetermined UE monitoring period. For example, in UE monitoring periods, a UE monitoring procedure is performed, so that the UE transmits the UE monitoring message to the eNB. Upon receipt of the UE monitoring message, the eNB transmits delivery confirmation information to the UE. The UE monitoring period is set as, for example, a period shorter than a TAU period. This allows the UE monitoring process to confirm the state of the UE even if the TAU period is lengthened. The eNB may transmit the UE monitoring message to the UE.

1 . (canceled) 
     
     
         2 . A communication system comprising:
 a user equipment;   a base station configured to perform radio communication with the user equipment;   a mobility management device configured to manage a mobility of the user equipment; and   a gateway device configured to perform data transmission/reception with the base station;   wherein the data transmission/reception between the base station and the gateway device is performed using an interface between the base station and the gateway device or via the mobility management device depending on a connection state between the base station and the gateway device.   
     
     
         3 . The communication system according to  claim 2 , wherein the data transmission/reception between the base station and the gateway device is performed using the interface between the base station and the gateway device when the base station and the gateway device are connected to each other. 
     
     
         4 . The communication system according to  claim 2 , wherein the data transmission/reception between the base station and the gateway device is performed via the mobility management device when the base station and the gateway device are not connected to each other. 
     
     
         5 . A user equipment used in a communication system comprising a user equipment, a base station configured to perform radio communication with the user equipment, a mobility management device configured to manage a mobility of the user equipment, and a gateway device configured to perform data transmission/reception with the base station,
 wherein the data transmission/reception between the base station and the gateway device is performed using an interface between the base station and the gateway device or via the mobility management device depending on a connection state between the base station and the gateway device.   
     
     
         6 . A base station used in a communication system comprising a user equipment, a base station configured to perform radio communication with the user equipment, a mobility management device configured to manage a mobility of the user equipment, and a gateway device configured to perform data transmission/reception with the base station,
 wherein the base station is configured to perform the data transmission/reception with the gateway device using an interface between the base station and the gateway device or via the mobility management device depending on a connection state between the base station and the gateway device.   
     
     
         7 . A mobility management device used in a communication system comprising a user equipment, a base station configured to perform radio communication with the user equipment, a mobility management device configured to manage a mobility of the user equipment, and a gateway device configured to perform data transmission/reception with the base station,
 wherein the mobility management device is configured to relay the data transmission/reception between the base station and the gateway device depending on a connection state between the base station and the gateway device.   
     
     
         8 . A gateway device used in a communication system comprising a user equipment, a base station configured to perform radio communication with the user equipment, a mobility management device configured to manage a mobility of the user equipment, and a gateway device configured to perform data transmission/reception with the base station,
 wherein the gateway device is configured to perform the data transmission/reception between the base station and the gateway device using an interface between the base station and the gateway device or via the mobility management device depending on a connection state between the base station and the gateway device.