Communication system and communication controlling method

Abstract

A communication method in LIPA/SIPTO architecture is provided which, when a user equipment (UE) is to connect from a serving area to an external network, allows re-selection of an optimal gateway. The communication method allows selecting a gateway apparatus physically or topologically close to a site, where the user equipment is attached.

1 . A communication method in Local IP Access (LIPA)/Selected IP Traffic Offload (SIPTO) architecture, the method comprising:
 a Mobility Management Entity (MME) sending a page signal to a user equipment, when a user equipment is in an EPS Connection Management (ECM)-IDLE state;   the user equipment, on receipt of the page signal, transmitting a service request signal to the MME;   the MME, on receipt of the service request signal, sending a 10 deactivate bearer request to a base station;   the base station transmitting an RRC (Radio Resource Control) connection reconfiguration to a user equipment;   the user equipment transmitting a notification of completion of the RRC connection reconfiguration to the base station;   the base station transmitting a deactivate bearer response to the MME; and   the user equipment initiating a packet data network connectivity procedure to cause the MME to perform re-selection of a gateway apparatus.   
     
     
         2 . The communication method according to  claim 1 , wherein the gateway apparatus includes at least one of a serving gateway apparatus and a packet data network gateway apparatus. 
     
     
         3 . A communication system in Selected IP Traffic Offload (SIPTO) architecture, the system comprising:
 a plurality of gateway apparatuses;   a Mobility Management Entity (MME);   a base station; and   a user equipment, wherein   the MME sends a page signal to the user equipment, when the user equipment is in an EPS Connection Management (ECM)-IDLE state;   the user equipment, on receipt of the page signal, transmits a service request signal to the MME;   the MME, on receipt of the service request signal, sends a deactivate bearer request to the base station;   the base station transmits an RRC (Radio Resource Control)connection reconfiguration to the user equipment;   the user equipment transmits a notification of completion of the RRC connection reconfiguration to the base station;   the base station transmits a deactivate bearer response to the MME; and   the user equipment initiates a packet data network connectivity procedure to cause the MME to perform re-selection of the gateway apparatus.   
     
     
         4 . The communication system according to  claim 3 , wherein the gateway apparatus includes at least a serving gateway apparatus and a packet data network gateway apparatus. 
     
     
         5 . A user equipment in a communication system by Selected IP Traffic Offload (SIPTO) architecture, wherein on receipt of a page signal from a Mobility Management Entity (MME), when the user equipment is in an EPS Connection Management (ECM)-IDLE state,
 the user equipment transmits a service request signal to the MME,
 the user equipment, on receipt of an RRC (Radio Resource Control) connection reconfiguration transmitted from a base station, transmits a notification of completion of the RRC connection reconfiguration to the base station; and 
 the user equipment initiates a packet data network connectivity procedure to cause the MME to perform re-selection of a gateway apparatus to which the user equipment is to be connected. 
   
     
     
         6 . The user equipment according to  claim 5 , wherein the gateway apparatus includes at least a serving gateway apparatus and a packet data network gateway apparatus.