JP5581169B2 - Mobile device and communication method - Google Patents

Description

  The present invention relates to a mobile device that is communicatively connected to a packet network that provides various services outside a core network such as a PDN, and a communication method using the same.

  In recent years, a communication method such as LTE (Long Term Evolution) for performing new high-speed communication has been proposed. A communication network using the LTE system (hereinafter referred to as an LTE network) is used for a PDN which is an external network. It is generally known to connect (see Patent Document 1).

International Publication WO2008 / 114823

  When a wireless terminal tries to connect to the LTE network, the wireless terminal performs an attach process (location registration process) and automatically establishes a communication connection to the PDN. Simultaneously performing the attach process and the PDN connection process is defined in the standard. Therefore, in the LTE network, when the wireless terminal disconnects the PDN connection, the wireless terminal automatically enters a detached state, cannot communicate with other devices, and is in a so-called call loss state.

  For this reason, in the environment of the LTE network, in order to prevent call loss, the so-called always-on connection function always makes a PDN connection. On the other hand, in a wireless communication system using a 3G network (hereinafter referred to as a 3G network), since the relationship between the PDN connection and the attach is separable, it should be detached even if the PDN connection is disconnected. Therefore, no call loss occurs. However, in the 3G network, only one communication path for PDN connection can be set.

  On the other hand, under the environment of the LTE network, the wireless terminal can set two communication accounts for PDN connection. Accordingly, when the wireless terminal has set two communication paths for PDN connection in the LTE network, when the wireless terminal moves from the LTE network to the 3G network environment due to handover or the like, the wireless terminal maintains two PDN connections. There is a problem that you can not.

  Therefore, in the present invention, even when moving to an environment in which the number of PDN connections is limited, such as a handover from an LTE network to an environment of 3G network, An object is to provide a communication method.

In order to solve the above-described problems, a mobile device of the present invention includes a storage unit that stores a default PDN to be connected in a mobile device connected to two communication networks having different numbers of PDNs that can be connected simultaneously. When connecting to one of the two communication networks, the default PDN connection means for connecting to the default PDN stored in the storage means and the number of PDNs that can be connected simultaneously are the same When there is a new connection request for another PDN that is not the default PDN when the default PDN connection means is connected to one more communication network that is set, the connection to the other PDN is made. Other PDN connection means, a handover means for handing over from the one communication network to the other communication network, and a handover by the handover means. When Ba is made, while the cutting means for cutting the connected state for the connected said default PDN by default PDN connection means, connection by the other PDN connection means have been made, deny deny communication to said default PDN And the other PDN connection means is configured to maintain a connection state with respect to the other PDN in the other communication network.

Further, the communication method of the present invention is a communication method of a mobile device connected to two communication networks having different numbers of PDNs that can be connected simultaneously, and a storage step of storing a default PDN to be connected in a storage unit; A default PDN connection step of connecting to a default PDN stored in the storage means when connecting to one communication network in which the number of PDNs that can be simultaneously connected is set to be larger than that of other communication networks; When a connection to a default PDN is maintained in the PDN connection step, and there is a new connection request for another PDN that is not the default PDN, the other PDN connection step for connecting to the other PDN and the one communication A handover step of handover from the network to the other communication network, and the handover step When Ndooba is made, while the said connected from the default PDN connection step and a cutting step for cutting the connected state to the default PDN, connection by the other PDN connection step has been made, deny deny communication to said default PDN In the other communication network, the other PDN connection step is configured to maintain a connection state with respect to the other PDN.

According to the present invention, when connecting to one communication network in which the number of PDNs that can be simultaneously connected is set larger than that of other communication networks, the connection is made to the default PDN that is the initial value, and the connection to the default PDN is established. When a new connection request is made to another PDN while being maintained, the other PDN is connected. When a handover is performed from one communication network to another communication network, the connection state with respect to the already connected default PDN is disconnected and the connection state with respect to the other PDN is maintained. As a result, even when the communication network is limited in the number of PDN connections, communication with other PDNs can be continued. Furthermore, while a connection is made to another PDN, the load on the network can be reduced by refusing communication with the default PDN.

In addition, the mobile device of the present invention is a mobile device connected to two communication networks having different numbers of PDNs that can be connected at the same time, a storage unit that stores a default PDN to be connected, and a connection between the two communication networks. When connecting to one of the communication networks, the default PDN connection means connected to the default PDN stored in the storage means and the number of PDNs that can be connected simultaneously are set to be larger than those of the other communication networks. When there is a new connection request for another PDN that is not the default PDN when the default PDN connection means is connected to the communication network, other PDN connection means for connecting to the other PDN; Handover means for performing handover from the one communication network to the other communication network, and when handover is performed by the handover means, Disconnect state for said default PDN connected by fault PDN connection means, the connection by the other PDN connection means is made, and a cutting means for cutting the connection to the default PDN, in the other communication network The other PDN connection means maintains a connection state with respect to the other PDN, and the default PDN connection means performs connection processing with respect to the default PDN again when the connection state by the other PDN connection means is disconnected Do.
In addition, the communication method of the present invention is a communication method of a mobile device connected to two communication networks having different numbers of PDNs that can be connected simultaneously. A default PDN connection step of connecting to a default PDN stored in the storage means when connecting to one communication network in which the number of PDNs that can be simultaneously connected is set to be larger than that of other communication networks; When a connection to a default PDN is maintained in the PDN connection step, and there is a new connection request for another PDN that is not the default PDN, the other PDN connection step for connecting to the other PDN and the one communication A handover step of handover from the network to the other communication network, and the handover step Disconnecting the default PDN connected from the default PDN connecting step, and disconnecting the default PDN when connected by the other PDN connecting step. In the other communication network, the other PDN connection step maintains a connection state with respect to the other PDN, and the default PDN connection step is configured such that when the connection state by the other PDN connection step is disconnected, The connection process is performed again for the default PDN.

According to the present invention, when connecting to one communication network in which the number of PDNs that can be simultaneously connected is set larger than that of other communication networks, the connection is made to the default PDN that is the initial value, and the connection to the default PDN is established. When a new connection request is made to another PDN while being maintained, the other PDN is connected. When a handover is performed from one communication network to another communication network, the connection state with respect to the already connected default PDN is disconnected and the connection state with respect to the other PDN is maintained. As a result, even when the communication network is limited in the number of PDN connections, communication with other PDNs can be continued. Further, when a connection is made to another PDN, the connection to the default PDN is disconnected, and when the connection state to the other PDN is disconnected, the connection process is performed again on the default PDN, so that a plurality of PDNs are connected. Either one can be disconnected and connected as necessary, and the load on the network can be reduced.

In the mobile device of the present invention, it is preferable that the one communication network is an LTE (Long Term Evolution) communication network and the other communication network is a 3G (3 ^rd Generation) communication network.

  According to the present invention, the LTE communication network and the 3G communication network are used. In the LTE communication network, generally, a plurality of PDNs can be extended. On the other hand, in a 3G communication network, only one PDN can be installed. By applying to such a communication network, when a handover is performed from the LTE communication network to the 3G communication network, the connection state of the PDN determined by default is disconnected, so that the PDN that is connected and connected in the LTE communication network is continuously connected. It is possible to achieve a reliable communication.

  In the mobile device of the present invention, as the default PDN, a network capable of providing a network connection service using a server arranged in a telecommunications carrier's gateway system is set, and the other PDN is connected to the communication It is preferable that the network is capable of providing a network service using a server arranged outside the provider's gateway system.

  According to the present invention, it is possible to provide a network connection service by a server arranged in a telecommunications carrier's gateway system, and applied to a PDN using servers arranged inside and outside the telecommunications carrier's gateway system. By using a default network as the default PDN, for example, for a communication network in which an attachment and a PDN connection are defined as a set, such as an LTE communication network, cooperation processing in the communication carrier is effectively performed. be able to. That is, since the telecommunications carrier holds information on various contractors, etc., a server in the telecommunications carrier's gateway system is not used for the one that is always PDN connected like the LTE communication network. If priority is given to connecting to the used PDN, the information can be used easily and quickly. Therefore, it can be expected to provide a communication service more suitable for the user in providing the communication service.

  According to the present invention, communication with a PDN can be continuously performed even in a communication network in which the number of PDN connections is limited.

1 is a system configuration diagram of a communication system 10 using a mobile device 100 of the present embodiment. 3 is a block diagram showing functions of mobile device 100. FIG. 2 is a hardware configuration diagram of a mobile device 100. FIG. FIG. 10 is a sequence diagram up to the point of disconnecting the connection state with respect to the first connected PDN. FIG. 10 is a sequence diagram when a PDN disconnection process is performed by handover from a PDN connection state thereafter. FIG. 11 is a sequence diagram when disconnecting the connection state to the mobile terminal NW mode PDN when connected to the packet communication mode PDN while in the LTE network.

  Embodiments of the present invention will be described with reference to the accompanying drawings. Where possible, the same parts are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a system configuration diagram of a communication system 10 using the mobile device 100 of the present embodiment. As shown in FIG. 1, the communication system 10 includes a 3G communication system 201, an LTE communication system 202, an exchange 203, a PDN (Packet Data Network) 204a, and a PDN 204b. In the communication system 10, the mobile device 100 can move under the network environment of the 3G communication system 201 or the LTE communication system 202. The mobile device 100 can be connected to the PDN 204a or the PDN 204b via the exchange 203 under the network environment of each communication system. The 3G communication system 201 and the LTE communication system 202 form a core network, and the PDN 204a and the PDN 204b are networks other than the core network and are packet data networks that provide various services. For example, the PDN 204a is a network (hereinafter referred to as an NW mode PDN for a portable terminal) for providing an Internet connection service using a server arranged in a telecommunications carrier's gateway system. For example, a PDN for an i-mode communication service. I-mode is a registered trademark. The PDN 204b is a network (hereinafter referred to as packet communication) that provides an Internet connection service via an ISP (Internet Service Provider) other than the i-mode communication service, for example, a general ISP (Internet Service Provider) arranged outside the gateway system. Mode PDN).

  The mobile device 100 that is connected to the communication system 10 will be described. FIG. 2 is a block diagram showing functions of mobile device 100. The mobile device 100 includes a default PDN storage unit 101 (storage unit), a communication processing unit 102, an attach unit 108, a communication control unit 109, a handover control unit 112 (handover unit), and an operation unit 113. . Further, the communication processing unit 102 includes a mobile terminal NW communication processing unit 103 and a packet communication processing unit 107. Further, the portable terminal NW communication processing unit 103 includes, as its functions, a PDN connection unit 104 (default PDN connection unit, other PDN connection unit), a PDN disconnection unit 105 (disconnection unit), and a rejection unit 106 (rejection unit). Have. The communication control unit 109 includes an LTE communication unit 110 and a 3G communication unit 111.

  FIG. 3 is a hardware configuration diagram of the mobile device 100. As shown in FIG. 3, the mobile device 100 shown in FIG. 2 physically includes a CPU 11, a RAM 12 and a ROM 13 that are main storage devices, an input device 14 such as a keyboard and a mouse that are input devices, and an output such as a display. The computer 15 includes a device 15, a communication module 16 that is a data transmission / reception device such as a network card, an auxiliary storage device 17 such as a hard disk, and the like. Each function described in FIG. 2 has the input device 14, the output device 15, and the communication module 16 under the control of the CPU 11 by reading predetermined computer software on the hardware such as the CPU 11 and the RAM 12 shown in FIG. 3. This is realized by reading and writing data in the RAM 12 and the auxiliary storage device 17. Hereinafter, each functional block will be described based on the functional blocks shown in FIG.

  The default PDN storage unit 101 is a part that stores a PDN that is set as an initial value and serves as a communication connection destination. In the present embodiment, the PDN 204a is set as a default PDN, for example, a PDN for NW communication for mobile terminals.

  The reason why the mobile terminal prepared NW communication PDN is set as the default PDN is as follows. That is, as described above, the LTE network requires that the location registration process and the PDN connection be performed simultaneously. Therefore, if the PDN connection cannot be made, the location registration process cannot be performed and a call loss occurs.

  When PDN connection is performed using an ISP or the like, the operation of the server that constructs the ISP may be unstable. When trying to connect to the PDN, if the server is down, the PDN cannot be connected, and as a result, the location registration process cannot be performed.

  Therefore, in the LTE network, it is necessary to be in an environment where PDN connection is surely performed. In the present embodiment, in order to perform PDN connection reliably, PDN connection is preferentially made to a server arranged in a system constructed by a communication carrier. More specifically, a telecommunications carrier has built a gateway system for connecting a public communication line and another network, and a server for performing PDN connection such as connection to the Internet is arranged in the gateway system. Has been. As described above, the server arranged in the gateway system of the telecommunications carrier is naturally maintained and managed by the telecommunications carrier, and can operate stably.

  By setting a server arranged in such a telecommunications carrier's gateway system as a default PDN, it is possible to prevent a state of call loss in the LTE network with high probability.

  The communication processing unit 102 includes a mobile terminal NW communication processing unit 103 and a packet communication processing unit 107. The mobile terminal NW communication processing unit 103 is a part that executes communication processing for connecting to an external network, is a communication connection service provided by a communication carrier, and is a part that executes packet communication for mobile terminals. .

  The packet communication processing unit 107 is a part that executes a communication process for connecting to an external network, and is a part that executes a packet communication for connecting to the Internet, which is a communication connection service provided by a communication carrier. It is.

  The mobile terminal NW communication processing unit 103 enables packet communication more specialized for the service of the communication carrier. For example, an Internet connection using a server arranged in the line of the communication carrier This is functionally distinguished from the packet communication processing unit 107 in this respect. The packet communication processing unit 107 connects to the Internet using a server (ISP) arranged outside the line of the communication carrier.

  Further, the mobile terminal NW communication processing unit 103 will be described. The portable terminal NW communication processing unit 103 includes a PDN connection unit 104, a PDN disconnection unit 105, and a rejection unit 106.

  The PDN connection unit 104 is a part that connects to a PDN that is an external network that provides various services other than the core network.

  When the mobile device 100 is located in the LTE network and the attach unit 108 performs an attach process, the PDN connection unit 104 establishes a communication path for the NW mode PDN for the mobile terminal, and always The connection state is maintained.

  In addition, when the mobile device 100 is located in the 3G network, the PDN connection unit 104 terminates the packet communication and disconnects the communication connection state with the packet communication PDN. A communication path is established for the PDN for communication and communication connection is established.

  The PDN disconnection unit 105 is a part that performs a disconnection process on the PDN that is always connected by the PDN connection unit 104. This PDN disconnection unit 105 is used when handover processing is performed by the handover control unit 112 and the mobile terminal moves from the LTE network to the 3G network and is connected to the mobile terminal NW mode PDN and the packet communication PDN. Is to release the connection state with respect to the NW mode PDN for the mobile terminal and to disconnect the connection, and to disconnect the PDN stored in the default PDN storage unit 101.

  In addition, the PDN disconnection unit 105, when connected to the mobile terminal NW mode PDN and connected to the packet communication PDN in order to start packet communication by a user operation, is used for the mobile terminal NW mode PDN. The communication connection state for is disconnected.

  When the mobile device 100 is located in the LTE network and the mobile device 100 is connected to both the mobile terminal NW mode PDN and the packet communication PDN, the refusal unit 106 responds to the mobile terminal NW mode PDN. Even if communication occurs, it is a part that rejects the communication.

  The packet communication processing unit 107 is a communication processing unit for performing packet communication with the so-called Internet, and is a part that performs communication by PDN connection to a PDN that is a network for Internet packet communication. When receiving an instruction to perform packet communication by a user operation, the packet communication processing unit 107 automatically establishes communication connection with the packet communication PDN and automatically terminates the packet communication. The communication connection state with the PDN for packet communication is disconnected.

  The attach unit 108 is a part for registering the location in the communication system 10 (network).

  The communication control unit 109 includes an LTE communication unit 110 and a 3G communication unit 111.

  The LTE communication unit 110 is a part for communication connection to a so-called LTE network, and is a part for communication connection to the LTE communication system 202.

  The 3G communication unit 111 is a part for communication connection to a so-called 3G network, and a part for communication connection to the 3G communication system 201.

  The handover control unit 112 is a part that performs switching between base stations in the 3G network and the LTE network, and is a part that performs so-called handover processing.

  The operation unit 113 is a part that receives a user operation, and is, for example, a keyboard. In the present embodiment, the user can instruct via the operation unit 113 whether to perform communication using the portable terminal NW or perform packet communication.

  Operations of the mobile device 100 and the communication system 10 configured as described above will be described. 4 and 5 are sequence diagrams showing processing for switching PDNs when the mobile device 100 performs handover between the 3G communication system 201 and the LTE communication system 202. FIG. 4 is a sequence diagram up to the point of disconnecting the initial PDN connection state, and FIG. 5 is a sequence diagram from the point where the PDN connection state is subsequently established.

  In the mobile device 100 in the connection environment of the LTE communication system (symbol X), when the power is turned on, the location registration processing is performed by the attach unit 108 and the PDN connection unit 104 is connected to the mobile terminal NW mode PDN A request is made. Then, the PDN connection unit 104 receives a response from the communication system to the effect that the connection to the mobile terminal NW mode PDN has been completed (S101). When this response is received, the mobile terminal is always connected to the NW mode PDN for mobile terminal (reference A).

  When the connection of the mobile terminal NW mode PDN by the PDN connection unit 104 is completed, the mobile terminal NW communication processing unit 103 uses the mobile terminal NW communication (for example, i-mode communication or i-mode communication). Mail transmission / reception is performed, and the communication ends (S102). Since this operation is an arbitrary operation by the user, such an operation may not occur.

  Then, the packet communication processing unit 107 makes a packet communication connection request to the general Internet by a user operation (S103). In response to the connection request, a connection request for packet communication to the Internet is made to the communication system, and by receiving a response from the communication system, communication establishment for Internet packet communication is established (S104). During this time, the packet communication PDN is connected (reference B).

  When the packet communication PDN is in a connected state, even if the mobile terminal NW mode PDN is in a connected state, communication to the PDN may be rejected by the rejection unit 106. Thereby, the traffic load in the LTE network can be reduced.

  Thereafter, predetermined communication is performed by the packet communication processing unit 107, and upon receiving a request for disconnection of Internet packet communication by a user operation (S105), end processing of Internet packet communication is performed (S106). When the mobile device 100 moves from the LTE network to the 3G network, the handover control unit 112 transmits a 3G transition command, and receives a response to the command, thereby performing a handover process (S107).

  As a result of this handover processing, the mobile device 100 moves to the 3G network (symbol Y), and when the packet communication processing unit 107 requests Internet packet communication by a user operation (S108), the mobile terminal NW mode PDN Is cut by the PDN cutting unit 105. Then, when the disconnection completion message for the mobile terminal packet communication PDN is transmitted from the communication system, the disconnection process is completed (S109). Then, the connection state of the mobile terminal NW mode PDN is released. This is because in the 3G network, only one PDN communication path can be set.

  Next, description will be continued with reference to FIG. When the connection state of the mobile terminal NW mode PDN is disconnected by the PDN disconnection unit 105, the packet communication processing unit 107 issues a request for starting Internet packet communication instructed by the user, and the communication path is established. (S110). From this point, an Internet packet communication PDN is set (reference C). When Internet packet communication is performed and a communication disconnection instruction is received by a user operation (S111), the packet communication processing unit 107 performs communication termination processing for Internet packet communication (S112). In accordance with this processing, the connection state of the packet communication PDN is released.

  Thereafter, the PDN connection unit 104 makes a connection request to the mobile terminal NW mode PDN, which is the default PDN stored in the default PDN storage unit 101, and a connection process is performed (S113, symbol D). When the mobile device 100 moves from the 3G network to the LTE network, the handover control unit 112 sends an LTE transition command to the communication system, receives the completion of the LTE transition from the communication system, and performs a handover process (S114, code). X1).

  Through the handover process described above, the mobile device 100 performs a request process for Internet packet communication by the packet communication processing unit 107 in accordance with a user operation while in the LTE network (S116). Based on this, the packet communication PDN enters a connected state (reference E). During the connection, when the LTE network moves to the 3G network, the handover control unit 112 performs a handover process (S117, symbol Y1). At that time, in the 3G network, since only one communication path can be set in the PDN connection, the mobile terminal NW mode PDN set as the default PDN is disconnected by the PDN disconnection unit 105 (S118). , Symbol D).

  When receiving an instruction to end the communication of the Internet packet communication from the user, the packet communication processing unit 107 performs a communication end process (S119), and the connection to the NW mode PDN for the portable terminal is performed according to the communication end process. Processing is performed (S120), and a connection state is established with respect to the mobile terminal NW mode PDN (reference F).

  Thus, when moving from the LTE network to the 3G network, when connected to each of the mobile terminal NW mode PDN and the packet communication PDN, the default mobile terminal NW mode is set. Disconnect the PDN for use.

  Next, a modified example of the above sequence diagram will be described. FIG. 6 is a sequence diagram in the modification, and is a sequence diagram when disconnecting the connection state with respect to the NW mode PDN for mobile terminals when connected to the packet communication mode PDN when located in the LTE network.

  In the mobile device 100 in the connection environment of the LTE communication system (symbol X), when the power is turned on, the location registration processing is performed by the attach unit 108 and the PDN connection unit 104 is connected to the mobile terminal NW mode PDN A request is made. Then, the PDN connection unit 104 receives a response from the communication system to the effect that the connection to the mobile terminal NW mode PDN has been completed (S101). From the time of receiving this response, the mobile terminal is always connected to the NW mode PDN for mobile terminal (reference A1).

  When the connection of the mobile terminal NW mode PDN by the PDN connection unit 104 is completed, the mobile terminal NW communication processing unit 103 performs mobile terminal NW communication in accordance with a user operation, and the communication ends (S102). Since this operation is an arbitrary operation by the user, such an operation may not occur.

  Then, the packet communication processing unit 107 makes a packet communication connection request to the general Internet by a user operation (S103). In response to the connection request, a connection request for packet communication to the Internet is made to the communication system, and by receiving a response from the communication system, communication establishment for Internet packet communication is established (S104). During this time, the packet communication PDN is connected (reference B).

  When the packet communication PDN is connected, a disconnection request for the mobile terminal NW mode PDN that is already in the PDN connection state is transmitted from the mobile device 100, and the communication system responds to the disconnect request. The completion notification is transmitted to the mobile device 100 (S104a). By this process, the connection state with respect to the portable terminal NW mode PDN is disconnected (reference A1).

  Thereafter, predetermined communication is performed by the packet communication processing unit 107, and when a request for disconnecting the packet communication mode is made by a user operation (S105), the PDN connection request for the mobile terminal NW mode is requested from the PDN connection unit 104 of the mobile device 100. Is transmitted to the communication system, and connection processing is performed upon completion of the connection (S105a). That is, the portable terminal NW mode PDN is connected (reference A2). Then, a packet communication mode communication end signal is transmitted from the packet communication processing 107 of the mobile device 100, and in response to the completion signal, the packet communication mode PDN is disconnected (S106). As a result, the packet communication mode PDN is disconnected.

  Thereafter, the processes of S107, S108, and S109 in FIG. 4 are executed as necessary.

  In this way, two PDN connections can be established when located in the LTE network. However, in this modification, when a connection request for the packet communication mode PDN is received, the connection state is already established. The connection state of the mobile terminal NW mode PDN can be disconnected, and the load on the PDN connection in the LTE network can be reduced by setting the PDN connection state to one.

  Next, operational effects of the mobile device 100 of the present embodiment will be described. In the mobile device 100 of the present embodiment, the PDN connection unit 104 is connected to the PDN stored in the default PDN storage unit 101 when located in either the LTE communication network or the 3G communication network. Then, in the LTE communication network, which is one communication network in which the number of PDNs that can be simultaneously connected is set larger than that of other communication networks, it is connected to an NW mode PDN for mobile terminals (for example, an i-mode PDN). If there is a new connection request for another PDN (for example, mobile: Internet connection service using a general ISP), the PDN connection unit 104 connects to the other PDN. When the PDN connection state moves from the LTE communication network to the 3G communication network and the handover is performed by the handover control unit 11, the PDN disconnection unit 105 is for the mobile terminal that is the already connected default PDN. The connection state with respect to the NW mode PDN is disconnected, and the packet communication processing unit 107 maintains the connection state with respect to the packet communication PDN which is another PDN. As a result, even when the communication network is limited in the number of PDN connections, communication with other PDNs can be continued.

  Further, in the mobile device 100 of the present embodiment, while the packet communication processing unit 107 is connected to the packet communication PDN, the refusal unit 106 communicates with the mobile terminal NW mode PDN that is the default PDN. By refusing, the load on the network can be reduced.

  In the mobile device 100 of the present embodiment, when the packet communication processing unit 107 connects to the packet communication PDN, the PDN disconnection unit 104 disconnects the connection to the portable terminal NW mode PDN that is the default PDN. . Thereafter, when the packet communication processing unit 107 disconnects the connection state with respect to the packet communication PDN, the PDN connection unit 104 performs connection processing with respect to the mobile terminal NW mode PDN. Accordingly, any one of the plurality of PDNs can be disconnected and connected as necessary, and the load on the network can be reduced.

  Moreover, in the mobile device 100 of the present embodiment, the mobile device 100 is applied to a PDN that uses servers arranged inside and outside the telecommunications carrier's gateway system, and further by a server arranged in the telecommunications carrier's gateway system. By setting a network (for example, an i-mode PDN) that can provide a network connection service as a default PDN, a communication network that is determined to simultaneously perform location registration processing and PDN connection, such as an LTE communication network. With regard to, by setting a server built in the telecommunications carrier's gateway system as a PDN connection destination, a reliable PDN connection can be performed, and thus location registration can be performed reliably. .

  In addition, it can be expected that the communication processing in the communication carrier is effectively performed. In other words, since the telecommunications carrier holds information on various contractors, etc., a server in the telecommunications carrier's communication line is connected to a network that is always PDN-connected like the LTE communication network. If priority is given to connecting to the used PDN, the information can be used easily and quickly. Therefore, it can be expected to provide a communication service more suitable for the user in providing the communication service.

DESCRIPTION OF SYMBOLS 10 ... Communication system, 100 ... Mobile device, 101 ... Memory | storage part, 102 ... Communication processing part, 103 ... Communication processing part, 104 ... PDN connection part, 105 ... PDN disconnection part, 106 ... Rejection part, 107 ... Packet communication processing part , 108 ... attach unit, 109 ... communication control unit, 110 ... LTE communication unit, 111 ... 3G communication unit, 112 ... handover control unit, 113 ... operation unit, 201 ... 3G communication system, 202 ... LTE communication system, 203 ... exchange 204a: PDN, 204b: PDN.

Claims (6)

In a mobile device connected to two communication networks having different numbers of PDNs that can be connected simultaneously,
Storage means for storing a default PDN to be connected;
A default PDN connection means for connecting to a default PDN stored in the storage means when connecting to one of the two communication networks;
When the default PDN connection means is connected to one communication network in which the number of PDNs that can be connected simultaneously is set larger than that of other communication networks, a new PDN that is not the default PDN is newly added. If there is a connection request, other PDN connection means for connecting to the other PDN,
Handover means for handing over from the one communication network to the other communication network;
When a handover is performed by the handover means, a disconnecting means for disconnecting a connection state for the default PDN connected by the default PDN connection means;
A rejection unit that rejects communication with respect to the default PDN while the connection by the other PDN connection unit is made ,
In the other communication network, the other PDN connection means is a mobile device that maintains a connection state with respect to the other PDN. In a mobile device connected to two communication networks having different numbers of PDNs that can be connected simultaneously,
Storage means for storing a default PDN to be connected;
A default PDN connection means for connecting to a default PDN stored in the storage means when connecting to one of the two communication networks;
When the default PDN connection means is connected to one communication network in which the number of PDNs that can be connected simultaneously is set larger than that of other communication networks, a new PDN that is not the default PDN is newly added. If there is a connection request, other PDN connection means for connecting to the other PDN,
Handover means for handing over from the one communication network to the other communication network;
When the handover is performed by the handover unit, the connection state to the default PDN connected by the default PDN connection unit is disconnected, and when the connection is made by the other PDN connection unit, the connection to the default PDN is disconnected. Means and
In the other communication network, the other PDN connection means maintains a connection state with respect to the other PDN,
The default PDN connection unit is a mobile device that performs connection processing to the default PDN again when the connection state by the other PDN connection unit is disconnected. 3. The mobile device according to claim 1, wherein the one communication network is an LTE (Long Term Evolution) communication network, and the other communication network is a 3G (3rd Generation) communication network. As the default PDN, a network capable of providing a network connection service using a server arranged in a telecommunications carrier's gateway system is set,
4. The network according to claim 1 , wherein the other PDN is a network capable of providing a network service using a server arranged outside the gateway system of the communication carrier. 5. Mobile machine. In a communication method of a mobile device connected to two communication networks having different numbers of PDNs that can be connected simultaneously
A storage step of storing a default PDN to be connected in a storage means;
A default PDN connection step of connecting to a default PDN stored in the storage means when connecting to one communication network in which the number of PDNs that can be simultaneously connected is set to be larger than that of other communication networks;
When there is a new connection request for another PDN that is not the default PDN while the connection to the default PDN is maintained by the default PDN connection step, another PDN connection step for connecting to the other PDN;
A handover step of handing over from the one communication network to the other communication network;
When a handover is performed by the handover step, a disconnecting step of disconnecting a connection state for the default PDN connected from the default PDN connection step;
A rejection step of rejecting communication to the default PDN while the connection by the other PDN connection step is made ,
In the other communication network, the other PDN connection step maintains a connection state with respect to the other PDN. In a communication method of a mobile device connected to two communication networks having different numbers of PDNs that can be connected simultaneously,
  A storage step of storing a default PDN to be connected in a storage means;
  A default PDN connection step of connecting to a default PDN stored in the storage means when connecting to one communication network in which the number of PDNs that can be simultaneously connected is set to be larger than that of other communication networks;
  When there is a new connection request for another PDN that is not the default PDN while the connection to the default PDN is maintained by the default PDN connection step, another PDN connection step for connecting to the other PDN;
  A handover step of handing over from the one communication network to the other communication network;
  When handover is performed by the handover step, the connection state for the default PDN connected by the default PDN connection step is disconnected, and when the connection by the other PDN connection step is performed, disconnection for disconnecting the connection for the default PDN And comprising steps
  In the other communication network, the other PDN connection step maintains a connection state with respect to the other PDN,
  The default PDN connection step is a communication method for performing connection processing to the default PDN again when the connection state in the other PDN connection step is disconnected.

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