JP2005094138A - Mobile terminal, communication system, protocol termination device, and communication control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To switch a physical layer to a different communication bearer network while maintaining a high layer. <P>SOLUTION: The mobile terminal 10, capable of making two-way communication with a protocol terminator 30 having a dormant function and for terminating the physical layer and a high layer protocol, and including the dormant function connectable to each network adopting a plurality of communication bearer systems, is provided with: a measurement section for measuring a radio electric field strength of each communication bearer system; a determination section for determining whether or not the radio electric field strength of each communication bearer system is at a prescribed level or over; a decision section for shifting a communication state data call to a dormant state depending on a determination result with respect to a communication bearer system during communication or a communication bearer switching timing on the basis of user selection and deciding the communication bearer system to be retransmitted on the basis of the determination result of each communication bearer system; and a retransmission control section for making retransmission by using the communication bearer system to shift the communication state data call from the dormant state to a communication state. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a portable terminal having a dormant function that can be connected to each network of a plurality of communication bearer systems, and a physical layer and a higher level in communication with the portable terminal that are capable of bidirectional communication with the portable terminal and have the dormant function. The present invention relates to a communication system including a protocol termination device that terminates a layer protocol, a portable terminal that configures the communication system, a protocol termination device, and a communication control method.

  In recent years, the importance of information has been demanded socially, and information processing using a mobile phone, a personal computer, a PDA, etc. is indispensable. Under these circumstances, as the price of various data mobile communication services and the infrastructure development progress, mobile data communication that enables access to the Internet and local networks within companies, etc., as appropriate, regardless of time and place, has begun to spread. Yes.

  However, each existing data mobile communication service has restrictions on the communication providing area and communication speed due to the technical conditions of the radio communication bearer which is the physical layer, and compatibility between the respective data mobile communication services is not maintained. . For this reason, even when the user exists in an environment where a plurality of data mobile communication services can be used, during the communication of a certain data mobile communication service, the user moves outside the communication area of the corresponding data mobile communication service. Therefore, if the radio section temporarily falls into weak electrolysis, the corresponding communication is disconnected regardless of whether data is transmitted or received. At this time, a user who wishes to continue communication must consciously select a data mobile communication service suitable for the location and perform connection procedures such as dial-up again. That is, it is considered that there is room for improvement in terms of operability because there is annoyance such as having to repeat the same operation again and taking time for the connection process again.

  In addition, there is a data communication service widely adopting a method of dynamically assigning an IP address for each connection such as dial-up from the viewpoint of efficient use of IP address resources (see Patent Document 1 below). However, in this data communication service, the IP address used in the previous communication is different from the IP address issued at the time of dial-up connection again, and the service using the IP address as an identifier cannot be used continuously. Improvement in the technical aspect is also desired.

  On the other hand, even if it does not detect weak electrolysis in the wireless section, data movement that can send and receive data at a higher speed or lower price than the data mobile communication service in use during communication of a specific data mobile communication service Communication services may be available to users. However, in this case, it is possible to seamlessly connect to different mobile communication services without going through the “Process to change the IP address being used” or “Processing to temporarily disconnect the dial-up connection being used and perform the dial-up procedure again”. There is room for improvement from the viewpoint of improving convenience, such as the inability to change.

Further, as a means for improving the above, a method of allowing mutual handover in the radio section of each existing data mobile communication service and allowing communication to continue without the user being aware even if the radio section becomes weakly electrolyzed Can be considered. However, considering from the viewpoint of a communication service provider (so-called communication carrier) that provides each existing data mobile communication service, the existing data mobile communication service includes not only a wireless section but also a user authentication method and a core network architecture. However, the communication bearer method based on a different method is adopted. In addition, these communication bearer systems have been studied with different circumstances and have been standardized. For these reasons, in order to solve the above problems by mutual handover in the wireless section of the existing data mobile communication service, it is necessary to review the capital investment and network architecture in enormous time. Corresponding is considered inefficient and impractical.
JP-A-9-98190

  In the above prior art, it is difficult for the mobile terminal and the network device that terminate the higher layer protocol (Point-to-Point Protocol, etc.) to separate the wireless communication bearer that supports the higher layer protocol and the physical layer (independent). For this reason, if weak electrolysis in the wireless section is detected between the terminal that terminates the communication bearer and the network device, there is a problem in that the mobile terminal and the network device release the higher layer protocol and the communication is disconnected.

  However, a dormant function for controlling connection / release of a wireless section by activation / deactivation of user data (that is, transmission / reception of user data for a certain period of time) for the purpose of effective utilization of wireless section resources of a circuit switching mobile communication service. If not, temporarily release (disconnect) the radio bearer while maintaining a higher layer such as the PPP layer, and re-connect the released radio bearer when a user data transmission request is made again Function) has been devised. However, the single use of the dormant function cannot control the communication bearer system that is a physical layer. Therefore, even if the user is in an environment where a data mobile communication service (communication bearer method) other than the detection of weak electrolysis in a wireless section can be used, the user can move to a different data mobile communication service without releasing the higher layer protocol. I couldn't.

  In addition, a user in an environment that can use a data mobile communication service that enables data transmission / reception at a higher speed or lower price than the data mobile communication service being used during a dial-up connection using a specific data communication service However, the existing system framework using the dormant function could not change to a different data mobile communication service without disconnecting the communication.

  The present invention has been made to solve the above-described problem, and is capable of switching a physical layer to a different communication bearer network while maintaining a higher layer, a mobile terminal, a communication system, a protocol termination device, and a communication control method The purpose is to provide.

  In order to solve the above problems, a mobile terminal according to the present invention is capable of bidirectional communication with a protocol termination device that has a dormant function and terminates a physical layer and a higher layer protocol in communication with the mobile terminal. A portable terminal having a dormant function that can be connected to each network of the communication bearer system, and measuring means for measuring the radio field intensity for each of the plurality of communication bearer systems, and a radio power for each communication bearer system obtained by the measurement Determined for each communication bearer system whether or not the field strength is greater than or equal to a predetermined level, and determined by the own terminal at a predetermined communication bearer system switching timing based on a determination result on the communication bearer system during communication or user selection Based on the determination result for each communication bearer system, the data call in communication is transitioned to the dormant state. Re-transmission to determine a new communication bearer method to be transmitted and to re-transmit using the determined new communication bearer method, and to change the data call under communication led by the own terminal from the dormant state to the communication state And a control means.

  Such a portable terminal according to the present invention temporarily releases (disconnects) a communication bearer method while maintaining a higher layer such as a PPP layer when user data is not transmitted / received for a certain period of time. And a protocol termination device that also has a dormant function and terminates the physical layer and higher layer protocols, and a function of reconnecting the released communication bearer system when a user data transmission request is made again. Bi-directional communication is possible. Further, the portable terminal is connectable to each network of a plurality of communication bearer systems, the measuring means measures the radio field intensity for each of the plurality of communication bearer systems, and the determining means It is determined for each communication bearer system whether or not the radio field strength relating to each communication bearer system obtained by the measurement is equal to or higher than a predetermined level.

  Then, a predetermined communication bearer system switching timing based on a determination result regarding the communication bearer system during communication or user selection (for example, when the radio field intensity related to the communication bearer system during communication falls below a predetermined level, or a communication bearer during communication When a communication bearer system other than the system is selected by the user, etc.), the determining means keeps the data call being communicated under the initiative of the own terminal (the portable terminal) while maintaining the higher layer by the dormant function (ie, the dormant function) The communication bearer system is released), and a new communication bearer system to be retransmitted is determined based on the determination result regarding each communication bearer system. Further, the re-transmission control means re-transmits using the determined new communication bearer method, and the data call under communication led by the own terminal is changed from the dormant state to the communication state.

  As described above, the present invention is most capable of appropriately replacing the communication bearer system as the physical layer without releasing the higher layer protocol once the higher layer protocol (for example, PPP) is established. Main features.

  Further, according to the present invention, the user can appropriately switch the communication bearer system of the physical layer and continue the communication without recognizing without repeating the connection procedure such as dial-up again.

  In addition, according to the present invention, once the higher layer protocol is established, the higher layer protocol is maintained even after the transition to the dormant state. Therefore, since it is not necessary to negotiate again (LCP negotiation, IPCP negotiation, CCP negotiation, etc.) to establish a higher-level protocol when re-calling, the connection time for re-calling can be shortened compared to new calls. it can.

  In addition, according to the present invention, the physical layer replacement function and the dormant function are provided in the mobile terminal, and the functions provided in the generally sold personal computer, PDA, etc. can be used for the higher layer protocol function. . Therefore, the user can use the present invention only by newly preparing a portable terminal, without improving the existing personal computer or PDA.

  Furthermore, according to the present invention, since the user is not involved in a communication method higher than the higher layer protocol, the user can perform data communication using a necessary higher layer protocol without depending on the physical layer communication bearer method.

  The mobile terminal according to the present invention further includes a priority table storing priority information of a communication bearer method at the time of re-transmission set in advance, and the determining means has a radio field strength of the communication bearer method during communication. Communication bearer method having the highest priority when the radio field strength is equal to or higher than a predetermined level, among communication bearer methods other than the communication bearer method in communication, in accordance with the priority information stored in the priority table when the level is lower than a predetermined level Is preferably determined as a new communication bearer method to be retransmitted. In this case, the user can select the communication bearer method desired by the user for each re-transmission, and the communication bearer method at the time of re-transmission according to the conditions related to the communication bearer method (for example, charge, communication speed, etc.). The selection priority order can be customized for each user.

  On the other hand, the user may want to select the communication bearer method individually regardless of the preset priority order. Therefore, the mobile terminal according to the present invention further includes a selection operation means for selecting a communication bearer system other than the communication bearer system in communication, and the determination means re-determines the communication bearer system selected by the selection operation means. It is desirable to adopt a configuration that determines a new communication bearer method to be transmitted. Thereby, it becomes possible for a user to select a communication bearer system individually. In this case, it is desirable that the selection operation means can select only a communication bearer system having a radio field intensity of a predetermined level or higher.

  In addition, the mobile terminal according to the present invention includes a state notifying unit for notifying a user of a state of the terminal related to communication (for example, a state of communication, a dormant state, an empty state), and a state of the terminal being in communication. In some cases, it is desirable to further include use bearer notification means for notifying the user of the communication bearer method being used. Thereby, the user can easily recognize the state of the terminal relating to communication and the communication bearer method in use.

  The invention relating to the mobile terminal as described above can be regarded as an invention relating to a communication system including a mobile terminal and a protocol terminator, and can be described as follows.

  In a communication system according to the present invention, a portable terminal having a dormant function that can be connected to each network of a plurality of communication bearer systems, and capable of two-way communication with the portable terminal and having a dormant function and communicating with the portable terminal. A communication system including a protocol termination device for terminating a physical layer and a higher layer protocol, wherein a mobile terminal measures a radio field strength for each of a plurality of communication bearer systems, Determining means for determining whether or not the radio field intensity related to each communication bearer method is greater than or equal to a predetermined level, and a predetermined communication bearer method based on a determination result or a user selection regarding the communication bearer method in communication At the switching timing, the data call being communicated led by the terminal is changed from the communication state to the dormant state. Based on the determination result for each communication bearer method, a determination unit that determines a new communication bearer method to be retransmitted, and retransmits using the determined new communication bearer method, and the data being communicated led by the own terminal Retransmission control means for transitioning a call from a dormant state to a communication state is provided.

  Here, the aspect in which the mobile terminal further includes a priority table can be described as follows. That is, the mobile terminal according to the present invention further includes a priority table storing priority information of a communication bearer method at the time of re-transmission set in advance, and the determining means has a radio field strength of the communication bearer method during communication. Communication bearer method having the highest priority when the radio field strength is equal to or higher than a predetermined level, among communication bearer methods other than the communication bearer method in communication, in accordance with the priority information stored in the priority table when the level is lower than a predetermined level Is determined as a new communication bearer method to be retransmitted, and the portable terminal uses the data communication function of its own terminal or the data communication function of an external device connected to its own terminal to determine the communication It is desirable that data communication is performed by terminating a higher layer protocol with the protocol termination device via a bearer network.

  In addition, the aspect in which the mobile terminal further includes a selection operation unit for selecting a communication bearer method can be described as follows. That is, the mobile terminal according to the present invention further comprises a selection operation means for selecting a communication bearer system having a radio field strength of a predetermined level or higher among communication bearer systems other than the communication bearer system in communication, and the determining means includes The communication bearer method selected by the selection operation means is determined as a new communication bearer method to be retransmitted, and the mobile terminal is a data communication function of the own terminal or data held by an external device connected to the own terminal. It is desirable to use a communication function to terminate the higher layer protocol with the protocol termination device and perform data communication via the determined communication bearer network.

  The present invention can also be understood as an invention related to a protocol termination device or an invention related to a communication control method, and can be described as follows.

  The protocol termination device according to the present invention is capable of bidirectional communication with a portable terminal having a dormant function that can be connected to each network of a plurality of communication bearer systems, and has a dormant function and communicates with the portable terminal. Is a protocol termination device that terminates the physical layer and higher layer protocol in the mobile terminal, recognizes the process of transitioning the data call being communicated by the mobile terminal from the communication state to the dormant state, and removes the data call being communicated from the communication state Recognizing the first transition control means for transitioning to the dormant state and the process of transitioning the data call currently being communicated led by the portable terminal from the dormant state to the communication state, and transitioning the data call being communicated from the dormant state to the communication state Whether the communication bearer method at the time of retransmission is the same as the communication bearer method before the retransmission Or regardless, characterized in that it is capable terminating communication bearer mode during the re-transmitted as a physical layer.

  A communication control method according to the present invention is capable of bidirectional communication with a protocol termination device that has a dormant function and terminates a physical layer and a higher layer protocol in communication with a mobile terminal, and each network of a plurality of communication bearer systems A communication control method executed by a portable terminal having a dormant function that can be connected to a wireless terminal, a measurement step of measuring a radio field intensity for each of a plurality of communication bearer methods, and a radio power for each communication bearer method obtained by the measurement Determined for each communication bearer system whether or not the field strength is equal to or higher than a predetermined level, and at a predetermined communication bearer system switching timing based on a determination result on the communication bearer system during communication or user selection The data call in communication is changed to the dormant state by using the A determination step for determining a new communication bearer method to be retransmitted based on the information, and retransmitting using the determined new communication bearer method, and the data call being communicated led by the own terminal from the dormant state to the communication state And a retransmission control step for making a transition to.

  As described above, according to the present invention, the communication bearer method during communication while the user holds a high layer protocol (PPP or the like) established between the mobile terminal and the physical layer / high layer protocol termination device. The type can be switched at a timing when the electric field strength in the wireless section is deteriorated or at a timing requiring a communication bearer method according to the transmission / reception data capacity. As a result, even if the user wants to continue the communication but needs to switch the communication bearer method type for some reason, the disconnection operation is performed again if the environment that can use the communication bearer method of the switching destination is satisfied. It is possible to appropriately switch the communication bearer method to the optimum communication bearer method without performing troublesome operations such as connection operations and without changing the communication environment such as the IP address and communication connection (TCP, etc.).

  In addition, in the present invention, a dormant function is provided in a layer between the physical layer and the higher layer protocol in each of the mobile terminal and the physical layer / higher layer protocol terminator to realize separation control of the physical layer and the higher layer protocol. By doing so, the user can use the switched mobile communication data service using the present invention without changing the specifications of a personal computer, PDA, or the like.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 shows a configuration example of a communication system 1 in an embodiment of the invention. As shown in FIG. 1, a portable terminal 10A that does not have a data display processing function / higher layer protocol function or the like and a portable terminal 10B that has a data display processing function / higher layer protocol function or the like have a PHS (Personal Handyphone System) respectively. It can be connected to any of the network 21, the IMT (International Mobile Telecommunications-2000) network 22, and the wireless LAN network 23. Among these, the mobile terminal 10A is connected to a personal computer (an example of a device having a data display processing function, a higher layer protocol function, etc.) 11, and the mobile terminal 10B is connected to the physical layer / higher level by its own function. The PPP layer is terminated with the layer protocol termination device 30, and the ISP network 61, the Internet network 62, the corporate network 63, and the end-to-end network are terminated using the PPP layer via the physical layer / higher layer protocol termination device 30.・ Data communication at the end is possible.

  In addition, it terminates between the portable terminal 10 (general name of 10A, 10B) and UNI (User-Network-Interface) / LAC (L2TP Access Concentrator) termination device 25, or between the portable terminal 10 and LAC termination device 26. The physical layers to be connected are connected by a communication bearer method of PHS, IMT, or wireless LAN. Among these, when using the IMT communication bearer system, the mobile terminal 10 is connected to the UNI / LAC terminating device 25 via the IMT network 22 and the NNI (Network Node Interface) -UNI converter 24.

  Further, a tunneling protocol such as L2TP (Layer2 Tuning Protocol) is employed in the network layer between the UNI / LAC termination device 25 or the LAC termination device 26 and the physical layer / higher layer protocol termination device 30. Further, when establishing a PPP layer between the mobile terminal 10 and the physical layer / higher layer protocol terminator 30, the physical layer / higher layer protocol terminator 30 may be the RADIUS server 50A possessed by the ISP or the RADIUS server possessed by the enterprise. 50B is connected to the routers 41 and 42 through an authentication process using the RADIUS protocol.

  As shown in FIG. 13A, the portable terminal 10A includes a dormant function unit 71 that controls a dormant function, a plurality of bearer termination devices 72 that can terminate a plurality of communication bearer systems, and a physical layer that performs physical layer replacement control described later. And a replacement function unit 73. As shown in FIG. 13 (b), the mobile terminal 10B includes a higher layer protocol function unit 74 and data display processing in addition to the dormant function unit 71, the multiple bearer termination device 72, and the physical layer replacement function unit 73 provided in the mobile terminal 10A. A functional unit 75 is further provided.

  Among the above components, as shown in FIG. 14A, the physical layer replacement function unit 73 includes a measurement unit 73A that measures the radio field strength for each of the plurality of communication bearer systems, and each of the obtained measurement results. A determination unit 73B for determining whether or not the radio field intensity related to the communication bearer method is equal to or higher than a predetermined level, and a priority table storing priority information of the communication bearer method set at the time of retransmission When the radio field strength of the communication bearer system 73E and the communication bearer system in communication is below a predetermined level, the radio field of the communication bearer system other than the communication bearer system in communication is determined according to the priority information stored in the priority table 73E. A determination unit 73C that determines a communication bearer method having a strength higher than a predetermined level and having the highest priority as a new communication bearer method to be retransmitted is determined. Redialing and using Do communication bearer scheme configured to include a re-transmission controller 73D for shifting a data call in the communication with its own terminal led from the dormant state to the communication state.

  Further, as shown in FIG. 14 (b), the data display processing function unit 75 selects a communication bearer method other than the communication bearer method during communication and having a radio field strength of a predetermined level or higher. 75A of selection operation parts, the status notification part 75B which notifies a user of the state of the own terminal regarding communication, and the use bearer which notifies a user of the communication bearer system in use when the state of the own terminal is a communicating state And a notification unit 75C. 14C, when the communication bearer method is selected by the selection operation unit 75A, the determination unit 73C determines the selected communication bearer method as a new communication bearer method to be retransmitted.

  On the other hand, as shown in FIG. 1, the physical layer / higher layer protocol terminator 30 includes a dormant function unit 31, an LNS function unit 32, and a RADIUS client function unit 33 for functioning as a client for the RADIUS server. Is done.

  FIG. 2 shows a protocol stack between the devices in FIG. As indicated by arrows A1 and A2 in FIG. 2, both the portable terminal 10 and the physical layer / higher layer protocol termination device 30 have a dormant function.

  Next, an example of the form and display display of the mobile terminals 10A and 10B in the present embodiment will be described with reference to FIGS.

  FIG. 3 shows an example of an external appearance image and display display of the portable terminal 10B having a data display processing function, a higher layer protocol function, and the like. The state of each communication bearer system which is a physical layer is displayed by the antenna marks 12A to 12C. During the communication state (PPP link up and physical layer link up state), the antenna mark 12C of the communication bearer method (in this case, wireless LAN) in use as the physical layer is displayed in vermilion or the like, and other communication bearer type antennas are displayed. The marks 12A and 12B are displayed in black. It should be noted that the radio wave intensity in the radio section is always measured and displayed as an antenna mark for communication bearer systems other than those in use as the physical layer.

  Further, in the dormant state (PPP link up and physical link layer down state), the communication bearer antenna mark used until immediately before the transition to the dormant state blinks in vermilion. In an idle state (not communicating: PPP link down and physical layer link down state), all communication bearer antenna marks are displayed in black. The radio buttons 13A to 13C displayed under the antenna mark of each communication bearer method are used when changing the communication bearer method led by the user during the communication state. For example, in FIG. 3, the wireless LAN network is being used for communication (the antenna mark 12C is displayed in vermilion or the like), but if the user wants to switch to the IMT network, select the IMT network 13B with a radio button. (This operation is referred to as “communication bearer switching operation”). However, a communication bearer method in which the electric field strength in the wireless section is weak and communication is recognized to be impossible before switching cannot be selected with the radio button, and is excluded from the communication bearer method to be switched. Note that data during communication (for example, Web browsing, e-mail, etc.) is displayed as in the display example on the terminal display 14.

  FIG. 4 is an example of an appearance image of the mobile terminal 10A that does not have a data display processing function, a higher layer protocol function, or the like. The lamps 15A to 15C are lamps that indicate the state of each communication bearer system (PHS network, IMT network, wireless LAN network). For example, the PHS network is lit green, the IMT network is lit yellow, and the wireless LAN network is lit blue, and lighting of each lamp means that the radio field electric field strength of each communication bearer system is communicable. The three lamps 15A to 15C are always turned on or off in accordance with the electric field strength in the wireless section, regardless of the communication state, the dormant state, and the empty state. Further, during the communication state, the color of the communication bearer method being used as the physical layer is displayed by a CONN lamp (CONNECT lamp) 15D. For example, in FIG. 4, the same color as the PHS network lamp 15 </ b> A is displayed on the CONN lamp 15 </ b> D, which indicates that communication is being performed using the PHS network. In the dormant state, the CONN lamp 15D is lit red. In the empty state, the CONN lamp 15D is turned off. The portable terminal includes an antenna 15E.

  FIG. 5 shows an example of display on the personal computer 11 to which the portable terminal 10A not having the data display processing function, the higher layer protocol function, etc. is connected. This display screen is used when the communication bearer method is changed by the user in the communication state. For example, in FIG. 5, the IMT network is being used for communication, but if the user wants to switch to the PHS network, select “Switch to PHS (16A)” with the check button and select the execute button 17 (This operation is referred to as “communication bearer switching operation”). A communication bearer method that is recognized as being incapable of communication before switching because the electric field strength in the wireless section is weak, etc., cannot be selected with the check buttons 16A to 16C, and is excluded from the communication bearer method to be switched And Note that data during communication (for example, web browsing, e-mail, etc.) is displayed on a personal computer, PDA, or the like.

  FIG. 6 shows that when a mobile terminal detects that the radio field electric field strength of the communication bearer method during communication is below a predetermined level (weak electric field) and the mobile terminal automatically retransmits with another communication bearer method, the retransmit communication bearer method A screen for setting a priority order to be referred to when the mobile terminal itself automatically selects is shown. A portable terminal 10A that does not have a data display processing function, a higher layer protocol function, or the like can be displayed and operated by a personal computer, a PDA, or the like. The mobile terminal 10B having a data display processing function, a higher layer protocol function, and the like can be displayed and operated on the display of the mobile terminal itself. The user can set the priority by selecting one of the radio buttons 18. In the example of FIG. 6, priority 1: PHS network, priority 2: wireless LAN network, priority 3: IMT network are selected. The physical layer communication bearer switching due to the radio field weak electric field is performed by automatic control of the mobile terminal based on the priority set here.

  Next, call processing control in this embodiment will be described with reference to FIGS.

  FIG. 7 shows a call processing sequence at the time of new connection (processing necessary for transition from the idle state to the communication state). FIG. 7 shows a case where PHS is set to priority 1 of the communication bearer system. The portable terminal 10 performs connection control with the UNI / LAC terminator 25 via the PHS network 21 (S11). When the communication bearer (PHS) is established, the UNI / LAC device 25 establishes an L2TP session with the physical layer / higher layer protocol termination device 30 (S12). On the other hand, the mobile terminal 10 transmits a dormant layer connection request to the physical layer / higher layer protocol termination device 30 using the communication bearer and the L2TP session (S13), and receives the received physical layer / higher layer protocol. The terminating device 30 returns a dormant layer connection response (S14). When the physical layer / higher layer protocol termination device 30 returns the above-described dormant layer connection response, it understands that this connection call is a new connection call. Thereafter, negotiation for establishing a PPP link is performed between the mobile terminal 10 and the physical layer / higher layer protocol termination device 30 (S15), and the state transits to a communication state (S16). At this time, the physical layer / higher layer protocol terminator has a function to perform RADIUS authentication to the RADIUS server owned by the ISP network, corporate network, etc., and controls whether the user can connect or not through the ISP network, corporate network, etc. Make it possible.

  FIG. 8 shows a call control sequence for transitioning from the communication state to the idle state. FIG. 8 shows a case where PHS is used as a communication bearer during communication. During communication of user data (S21), when a disconnection operation (depending on a personal computer, PDA, etc.) is performed by the user's intention according to the user's intention, and the mobile terminal 10 recognizes the disconnection process, the mobile terminal 10 A dormant layer disconnection request is transmitted to the layer protocol termination device 30 (S22), and the physical layer / higher layer protocol termination device 30 that has received the request returns a dormant layer disconnection response to the portable terminal (S23). The physical layer / higher layer protocol termination device 30 understands that it is a request to disconnect this call processing when returning the above-described dormant layer disconnection response. Thereafter, negotiation (S24) for releasing the PPP link between the mobile terminal 10 and the physical layer / higher layer protocol termination device 30 and release processing of the PHS network and the L2TP are performed (S25), and the state transitions to an empty state. To do.

  FIG. 9 shows a communication bearer switching sequence associated with a weak field in the radio section of the communication bearer system during communication. FIG. 9 shows a call processing sequence in which a PHS radio section becomes a weak electric field in a state where PHS is used as a communication bearer, and the communication bearer is automatically switched to IMT. When the wireless section becomes a weak electric field in the communication state (S31), the processing flow A shown in FIG. 11 is performed (S32).

  That is, as shown in FIG. 11, in the processing flow A, first, it is determined whether there is a communication bearer system that can be used other than the bearer that is communicating (S51), and can be used other than the bearer that is communicating. If the communication bearer method exists, the state transits to the dormant state (S52). Then, the priority order information set in the priority table 73E (FIG. 14A) is compared with the available communication bearer methods (S53), and the communication bearer with the highest priority among the available communication bearer methods. Control is performed so as to re-transmit using the method (S54). On the other hand, if there is no available communication bearer system other than the bearer in communication in S51, the process proceeds to disconnection processing (S55).

  Hereinafter, in the processing flow A of FIG. 11, there will be described a case where there is a communication bearer method that can be used in addition to the bearer in communication and the mobile terminal 10 shifts to a re-transmission process through a dormant state.

  Next, the portable terminal 10 transmits a dormant layer temporary disconnection request to the physical layer / higher layer protocol termination device 30 (S33), and at the same time, disconnects the PPP layer from the physical layer and shifts to a controllable state. On the other hand, when the physical layer / higher layer protocol termination device 30 receives the above-described dormant layer temporary disconnection request, it understands that the mobile terminal 10 transitions to the dormant state, and releases the physical layer while maintaining the PPP layer. Perform (S34). Specifically, the L2TP session established with the UNI / LAC terminator 25 is disconnected (S34A), and the UNI / LAC terminator 25 leads the PHS which is the physical layer (S34B). Since the portable terminal 10 is in a state in which the PPP layer and the physical layer are separated and controllable, only the physical layer is disconnected while keeping the PPP layer, and the state transitions to the dormant state (S34C). At the same time, the mobile terminal 10 refers to the priority setting, automatically selects the communication bearer having the highest priority from the available communication bearers, and retransmits using the selected communication bearer (here, IMT). (S35). In addition, when there is no communication bearer that can be used at all due to the relationship between the electric field strengths in the wireless section, the state transits to a free state through the disconnection sequence shown in FIG.

  Then, the mobile terminal 10 establishes an IMT link with the UNI / LAC terminator 25 via the IMT network 22 (S36), and the UNI / LAC terminator 25 further communicates with the physical layer / higher layer protocol terminator 30. An L2TP session is established between them (S37). Thereafter, the portable terminal 10 transmits a dormant layer temporary connection request to the physical layer / higher layer protocol termination device 30 using the IMT link and L2TP session described above (S38). On the other hand, the physical layer / higher layer protocol termination device 30 that has received the dormant layer temporary connection request connects the PPP layer and the physical layer established by using the IMT link, which are held in the above, when the signal is received. A state in which data communication is possible again is prepared, and a dormant layer temporary connection response is transmitted to the mobile terminal 10 (S39). With the above control, the communication bearer supporting the physical layer can be switched from the PHS to the IMT without releasing the PPP layer as the radio section becomes a weak electric field.

  FIG. 10 shows a communication bearer switching sequence during user-initiated communication. In FIG. 10, an operation in which the user forcibly switches the communication bearer to the IMT (operation of the radio buttons 13 </ b> A to 13 </ b> C in FIG. 3 or the check buttons 16 </ b> A to 16 </ b> C in FIG. 5) while the PHS is used as the communication bearer is performed. The call processing sequence in which the communication bearer is switched to IMT by automatic control of the mobile terminal is shown. When the communication bearer switching operation is performed in the communication state (S41), the processing flow B shown in FIG. 12 is performed (S42).

  That is, as shown in FIG. 12, in the processing flow B, the mobile terminal 10 transitions to the dormant state (S61), and then controls to retransmit using the communication bearer method designated by the user (S62).

  Next, the portable terminal 10 transmits a dormant layer temporary disconnection request to the physical layer / higher layer protocol termination device 30 (S43), and at the same time, transitions to a state in which the PPP layer and the physical layer are separated and can be controlled. On the other hand, when the physical layer / higher layer protocol termination device 30 receives the above-described dormant layer temporary disconnection request, it understands that the mobile terminal 10 transitions to the dormant state, and releases the physical layer while maintaining the PPP layer. Perform (S44). Specifically, the physical layer / higher layer protocol termination device 30 disconnects the L2TP session established with the UNI / LAC termination device 25 (S44A), and the UNI-LAC device leads the PHS which is the physical layer. Disconnect (S44B). Since the portable terminal 10 is in a state in which the PPP layer and the physical layer are separated and controllable, only the physical layer is disconnected while keeping the PPP layer, and the state transitions to the dormant state (S44C). At the same time, the mobile terminal 10 re-transmits using the communication bearer (for example, IMT) designated by the user's communication bearer switching operation (S45).

  The mobile terminal 10 establishes an IMT link with the UNI / LAC terminator 25 via the IMT network 22 (S46), and the UNI / LAC terminator 25 further communicates with the physical layer / higher layer protocol terminator 30. An L2TP session is established (S47). Thereafter, the portable terminal 10 transmits a dormant layer temporary connection request to the physical layer / higher layer protocol termination device 30 using the IMT link and L2TP session described above (S48). On the other hand, the physical layer / higher layer protocol termination device 30 that has received the dormant layer temporary connection request uses the PPP layer and the IMT link that have been held as described above when the signal is received. The state in which the combined data communication is possible again is prepared, and a dormant layer temporary connection response is transmitted to the portable terminal (S49). Through the control as described above, the communication bearer supporting the physical layer can be switched from the PHS to the IMT without releasing the PPP layer by the user-driven communication bearer switching operation.

  As described above, according to the embodiment of the invention, the user is in communication while holding the higher layer protocol (such as PPP) established between the mobile terminal 10 and the physical layer / higher layer protocol termination device 30. It is possible to switch the communication bearer system type at a timing that requires a communication bearer system corresponding to the degradation of radio field electric field strength or the like and the transmission / reception data capacity. For this reason, even if the user wants to continue communication but needs to switch the communication bearer method type for some reason, the disconnect operation is performed again if the environment that can use the communication bearer method of the switching destination is satisfied. It is possible to appropriately switch the communication bearer method to the optimum communication bearer method without performing troublesome operations such as connection operations and without changing the communication environment such as the IP address and communication connection (TCP, etc.).

  In addition, a dormant function is provided in each layer between the physical layer and the higher layer protocol in each of the mobile terminal 10 and the physical layer / higher layer protocol termination device 30 to realize separation control of the physical layer and the higher layer protocol. Thus, the user can use the switched mobile communication data service without changing the specifications of the personal computer, PDA, or the like.

It is a block diagram of the communication system in embodiment of invention. It is a protocol stack figure which shows the protocol which each apparatus has. It is a figure which shows the structural example regarding the display of a portable terminal which comprises a high-order layer protocol function and a data display / processing function. It is a figure which shows the structural example regarding the display of a portable terminal which does not have a high-order layer protocol function and a data display / processing function. FIG. 5 is a diagram illustrating an example of an image displayed on a display such as a personal computer or a PDA when the mobile terminal of FIG. 4 is used. It is a figure which shows an example of a priority order setting screen. It is a figure which shows the call processing sequence at the time of new connection. It is a figure which shows the call control sequence for changing from a communication state to an idle state. It is a figure which shows the communication bearer switching sequence accompanying the radio area weak electric field of the communication bearer system in communication. It is a figure which shows the communication bearer switching sequence during communication by a user initiative. It is a flowchart which shows process flow A of the call control process in embodiment of invention. It is a flowchart which shows process flow B of the call control process in embodiment of invention. (A) is a block diagram of 10 A of portable terminals, (b) is a block diagram of 10 A of portable terminals. (A) is a block diagram of the physical layer replacement function unit 73, and (b) is a block diagram of the data display processing function unit 75.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Communication system 10, 10A, 10B ... Portable terminal, 11 ... PC, 12A, 12B, 12C ... Antenna mark, 13A, 13B, 13C ... Radio button, 14 ... Terminal display, 15A, 15B, 15C, 15D ... Lamp 15E ... Antenna, 16A, 16B, 16C ... Check button, 17 ... Execution button, 18 ... Radio button, 21 ... PHS network, 22 ... IMT network, 23 ... Wireless LAN network, 24 ... NNI-UNI converter, 25 ... UNI / LAC terminator, 26 ... LAC terminator, 30 ... physical layer / higher layer protocol terminator, 31 ... dormant function unit, 32 ... LNS function unit, 33 ... RADIUS client function unit, 41, 42 ... router, etc. 50A 50B ... RADIUS server, 61 ... ISP network, 62 ... Internet network, 63 ... enterprise network, 71 ... dormant function unit, 72 ... multiple bearer termination device, 7 3 ... Physical layer replacement function unit, 73A ... Measurement unit, 73B ... Determination unit, 73C ... Determination unit, 73D ... Re-transmission control unit, 73E ... Priority table, 74 ... High layer protocol function unit, 75 ... Data display processing function Part, 75A ... selection operation part, 75B ... state notification part, 75C ... use bearer notification part.

Claims (10)

A portable terminal having a dormant function and capable of bidirectional communication with a protocol terminating device that terminates a physical layer and a higher layer protocol in communication with a portable terminal, and capable of connecting to each network of a plurality of communication bearer systems A terminal,
Measuring means for measuring radio field strength for each of a plurality of communication bearer systems;
A determination means for determining, for each communication bearer system, whether or not the radio field strength related to each communication bearer system obtained by measurement is equal to or higher than a predetermined level;
Based on the determination result regarding the communication bearer method, the data call under communication led by the own terminal is shifted to the dormant state at the predetermined communication bearer method switching timing based on the determination result regarding the communication bearer method during communication. Determining means for determining a new communication bearer method to be retransmitted;
Re-transmission using the determined new communication bearer method, re-transmission control means for transitioning the data call under communication led by the own terminal from the dormant state to the communication state,
Mobile terminal equipped with. The portable terminal further includes a priority table storing priority information of a communication bearer method at the time of a preset retransmission,
When the radio field strength of the communication bearer method during communication falls below a predetermined level, the determining means, according to the priority information stored in the priority table, among communication bearer methods other than the communication bearer method during communication, Determine the communication bearer method with the highest priority when the radio field strength is a predetermined level or higher as a new communication bearer method to be retransmitted.
The mobile terminal according to claim 1. The mobile terminal further comprises a selection operation means for selecting a communication bearer method other than the communication bearer method during communication,
The determination means determines the communication bearer method selected by the selection operation means as a new communication bearer method to be retransmitted.
The mobile terminal according to claim 1. 4. The portable terminal according to claim 3, wherein the selection operation unit can select only a communication bearer system having a radio field intensity of a predetermined level or more. Status notification means for notifying the user of the status of the terminal for communication;
Use bearer notification means for notifying the user of the communication bearer method in use when the state of the own terminal is a communication state;
The mobile terminal according to any one of claims 1 to 4, further comprising: A portable terminal having a dormant function that can be connected to each network of a plurality of communication bearer systems, and capable of bidirectional communication with the portable terminal and having a dormant function and terminating physical layer and higher layer protocols in communication with the portable terminal A communication system configured to include a protocol termination device,
The mobile terminal is
Measuring means for measuring radio field strength for each of a plurality of communication bearer systems;
A determination means for determining, for each communication bearer system, whether or not the radio field strength related to each communication bearer system obtained by measurement is equal to or higher than a predetermined level;
Result of determination regarding communication bearer method during communication or determination result regarding each communication bearer method by transitioning a data call under communication led by the own terminal from a communication state to a dormant state at a predetermined communication bearer method switching timing based on user selection A determination means for determining a new communication bearer method to be retransmitted based on
A communication system comprising: a retransmission control unit configured to retransmit using the determined new communication bearer method, and to change the data call being communicated from the dormant state to the communication state under the initiative of the own terminal. The mobile terminal further includes a priority table storing priority information of a communication bearer method at the time of a preset retransmission,
When the radio field strength of the communication bearer method during communication falls below a predetermined level, the determining means, according to the priority information stored in the priority table, among communication bearer methods other than the communication bearer method during communication, The communication bearer method with the highest priority when the radio field strength is equal to or higher than a predetermined level is determined as a new communication bearer method to be retransmitted,
The portable terminal is
Using the data communication function of the own terminal or the data communication function of an external device connected to the own terminal, a higher layer protocol is exchanged with the protocol terminating device via the determined communication bearer network. Terminate and perform data communication,
The communication system according to claim 6. The mobile terminal further includes a selection operation means for selecting a communication bearer method having a radio field strength of a predetermined level or higher among communication bearer methods other than a communication bearer method in communication,
The determining means determines the communication bearer method selected by the selection operation means as a new communication bearer method to be retransmitted,
The portable terminal is
Using the data communication function of the own terminal or the data communication function of an external device connected to the own terminal, a higher layer protocol is exchanged with the protocol terminating device via the determined communication bearer network. Terminate and perform data communication,
The communication system according to claim 6. Two-way communication is possible with a mobile terminal having a dormant function that can be connected to each network of a plurality of communication bearer systems, and terminates the physical layer and higher layer protocols in communication with the mobile terminal having the dormant function A protocol terminator,
A first transition control means for recognizing a process of transitioning a data call being communicated led by a portable terminal from a communication state to a dormant state, and transitioning the data call being communicated from a communication state to a dormant state;
A second transition control means for recognizing a process of transitioning a data call in communication led by a portable terminal from a dormant state to a communication state, and transitioning the data call in communication from the dormant state to a communication state;
With
A protocol characterized in that the communication bearer method at the time of retransmission can be terminated as a physical layer regardless of whether the communication bearer method at the time of retransmission is the same as the communication bearer method before the retransmission. Termination equipment. A portable terminal having a dormant function and capable of bidirectional communication with a protocol terminating device that terminates a physical layer and a higher layer protocol in communication with a portable terminal, and capable of connecting to each network of a plurality of communication bearer systems A communication control method executed by a terminal,
A measurement step of measuring radio field strength for each of a plurality of communication bearer systems;
A determination step for determining, for each communication bearer method, whether or not the radio field strength related to each communication bearer method obtained by measurement is equal to or higher than a predetermined level;
Based on the determination result regarding the communication bearer method, the data call under communication led by the own terminal is shifted to the dormant state at the predetermined communication bearer method switching timing based on the determination result regarding the communication bearer method during communication. Determining a new communication bearer method to be retransmitted;
Re-transmission using the determined new communication bearer method, a re-transmission control step of transitioning the data call in communication led by the own terminal from the dormant state to the communication state;
A communication control method.

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