JP4440248B2 - Bearer selection method and mobile communication terminal - Google Patents

Description

  The present invention relates to a mobile communication network in which an area that supports a circuit-switched bearer that performs communication by circuit switching, an area that supports both a circuit-switched bearer and a packet bearer that performs communication by packet switching, exist. The present invention relates to a mobile communication terminal and a bearer selection method.

  The spread of digital mobile communication systems (PDC (Personal Digital Cellular telecommunication system), GSM (global system for mobile communication), IS-54, IS-95, etc.) is remarkable, and support of data communication is regarded as important in mobile communication. It has become so. Therefore, a PDC-P (PDC Packet) method using a packet switching method, a GPRS (General Packet Radio System) method based on GSM, an HDR (High Data Rate) method based on IS-95, and the like have been developed. By using communication using such packets, it is possible to send and receive e-mails and access the Internet. In addition, sending and receiving e-mails and accessing the Internet using current circuit switching methods are also performed.

  The circuit switching method is a switching connection method in which a dedicated communication channel is set between terminals when communicating, and the channel is occupied until the communication is completed. A typical circuit switching system is a telephone network for a fixed telephone. is there. In circuit switching, the transmission speed (bandwidth) of the set communication channel is ensured regardless of the traffic conditions of the entire network, so there is no characteristic of end-to-end transmission delay time variation between terminals. It is suitable for services that are sensitive to degradation of service quality due to fluctuations in transmission delay time, such as telephone calls and video conferencing. Furthermore, although it is suitable for transmitting a large amount of data at a time, it is not suitable for a method of using a line for a long time because the frequency of traffic increases.

  The packet switching method is a switching method in which data is transmitted using a packet of a certain format. In packet switching, a store-and-send type packet switch is used as a packet relay node, and the relay line between packet switches is used in a large number of packets from many users, resulting in high line utilization and lower communication costs. Can be made. In addition, when a certain communication section is congested or malfunctions, the detour route is automatically followed in units of packets, so that the communication reliability is improved. However, the end-to-end transmission delay time varies depending on the traffic state.

In the mobile communication network, if the above-described circuit switching is used, the communication channel assignment process is executed for each call and the communication channel is assigned, so that it takes time to set up the call and is not suitable for short-time communication. The problem arises. In addition, there is a problem that the communication channel cannot be used effectively even when burst communication is performed in which the communication time is short although the data is transmitted for a long time. Further, when the frequency of traffic increases, all communication channels are in use, and a free channel cannot be assigned to a new call, resulting in a call loss.
On the other hand, when packet switching is used in a mobile communication network, although the line usage rate can be increased, there is a problem that packets are collided with each other and are not suitable for long-time communication. In addition, when the frequency of traffic increases, the number of packet collisions increases, resulting in a transmission delay due to retransmission.

  In the current mobile communication network, since circuit switching is generally used, nodes such as base stations and switching stations constituting the mobile communication network have a circuit switching function. There is also a mobile communication network including a node having a packet switching function. Further, it is conceivable to provide a packet switching function in addition to the circuit switching function to some of the nodes constituting the mobile communication network. In this case, there is a service area configured by the node and a service area that supports only the circuit switching function, and communication using circuit switching can be performed in all service areas. The packet communication to be used cannot be performed unless it is located in a service area that supports the packet switching function. The circuit switching function is provided by a circuit switching bearer, and the packet switching function is provided by a packet bearer.

  Therefore, an object of the present invention is to provide a bearer selection method and a mobile communication terminal capable of selecting an efficient bearer between a circuit switched bearer and a packet bearer.

The bearer selection method of the present invention capable of achieving the above object includes a first area supporting a circuit-switched bearer that performs communication by circuit switching, a packet bearer that performs communication by packet switching and the circuit-switched bearer. Is a bearer selection method in a mobile communication network in which there is a second area that supports both, and when a mobile communication terminal located in the first area or the second area accesses the web Has a file size threshold defined for each number of time slots that can be used in packet switching, and the mobile communication terminal acquires the number of time slots that can be used with broadcast information from the base station and can use the acquired time slot. If the file size to be loaded exceeds the threshold value for the file size threshold determined by the number of time slots, With selecting Ttobeara, if it exceeds the threshold value selecting circuit switched bearer, so that access to the web by using the selected bearer.

The mobile communication terminal of the present invention capable of achieving the above object communicates with a first area supporting a circuit-switched bearer that performs communication by circuit switching and the circuit-switched bearer by packet switching. A mobile communication terminal in a mobile communication network in which a second area that supports both packet bearers exists, and when accessing the web , the file size of each time slot that can be used in packet switching A threshold is defined, the number of usable time slots is obtained from the broadcast information from the base station, and the size of the file to be loaded is smaller than the file size threshold defined by the obtained usable number of time slots. together until exceeding the threshold value is selected packets bearer, if it exceeds the threshold value by selecting the circuit switched bearer, the Use-option bearer so that access to the web.

According to the present invention, when accessing the web, a file size threshold is set for each number of time slots that can be used in packet exchange, and the number of time slots that can be used in broadcast information from the base station. If a file bearer is selected for the file size threshold determined by the number of available time slots and the file size to be loaded exceeds the threshold, and if the threshold is exceeded, Since the circuit-switched bearer is selected , efficient bearer selection according to the application can be made possible. By performing efficient bearer selection in this way, the performance of the mobile communication network is improved and a large number of users can be accommodated with few resources.

FIG. 1 shows an outline of the configuration of a mobile communication network according to an embodiment of the present invention having a mobile communication terminal of the present invention.
The mobile communication network according to the present invention has a large number of cells, but FIG. 1 shows only two cells A and B. Further, although nodes constituting the mobile communication network are shown, only the nodes related to cell A and cell B are shown. A base station (BS) 2 is provided in the cell A, and the base station 2 performs communication control of a mobile device that is a mobile communication terminal located in the cell A. The base station 2 includes a circuit switching bearer 2a, and a circuit switching function is provided by the circuit switching bearer 2a. In addition, a base station (BS) 3 is provided in a cell B adjacent to the cell A, and the base station 3 performs communication control of a mobile device that is a mobile communication terminal located in the cell B. The base station 3 has a circuit switched bearer 3a and a packet bearer 3b. The circuit switched bearer 3a provides a circuit switching function, and the packet bearer 3b provides a packet switching function. That is, the base station 2 does not have a packet switching function, but the base station 3 has a packet switching function. Although all base stations including a base station not shown have a circuit switching function, a base station having a packet switching function is a part thereof.

  Here, when the mobile device 1 is located in a cell A including a base station 2 that supports only the circuit switching function, the data communication is performed using the circuit switching bearer 2a when performing data communication. . Therefore, each time data communication is performed, it is necessary to execute a communication channel assignment process and assign a communication channel to perform data communication. Large data can be efficiently communicated. Efficient communication is not possible. On the other hand, when the mobile station 1 is located in a cell B including the base station 3 that supports both the circuit switching function and the packet switching function, the circuit switching bearer 3a or the packet bearer 3b is used when performing data communication. Data communication can be performed by selecting either one. Therefore, large-size data communication can be efficiently performed using the circuit-switched bearer, and small-size data communication can be efficiently performed using the packet bearer 3b.

Therefore, in the mobile communication network according to the present invention, the mobile station 1 executes the mobile station location process shown in the flowcharts shown in FIGS. 2 and 3 to support the circuit switching function and the packet switching function of the cell B and the like. The mobile device 1 is located in the cell as much as possible.
Before explaining the flowchart of the mobile station location process shown in FIG. 2 and FIG. 3, the establishment of the connection between the mobile station and the base station as a premise will be described. When power is turned on in a mobile device that is a mobile communication terminal, a broadcast channel (BCCH) transmitted from the base station is first searched to establish control with the base station. In this case, since there are a plurality of base stations (cells) around the mobile device, the mobile device can receive broadcast channels from the plurality of base stations. This broadcast channel candidate channel is called a perch channel, and a plurality of channels as perch channel candidates are stored in advance in the mobile device at the stage of manufacturing the mobile device. Therefore, when the power is turned on, the mobile station scans the perch channel to detect the carrier power level of each perch channel. Next, a level order table of perch channels arranged in order of carrier power level is created, synchronized with the corresponding channel in the order of this level order table, confirmed as a common control channel, and broadcast channel is received. Thus, the connection between the mobile device and the base station is established.

  In the mobile communication network according to the present invention, the broadcast channel is transmitted from the broadcast information message of the broadcast channel received so that the mobile station is located in the cell supporting the circuit switching function and the packet switching function as much as possible. It recognizes whether or not the base station that is supporting supports the packet switching function. Here, if the base station with which the connection has been established supports the packet switching function, it may be located in the cell of the base station as it is. If the packet switching function is not supported, whether the base station that receives the broadcast channel of the next perch channel in the level order table and transmits the broadcast channel supports the packet switching function. Recognize whether or not. Also in this process, if the base station transmitting the broadcast channel does not support the packet switching function, the above process is repeated. As a result, if there is a cell that also supports a packet switching function located in the vicinity, it can be located in that cell. However, there is a possibility that it may take a processing time for the user to feel uncomfortable from the point of turning on the power in order to place the cell in the cell that also supports the packet switching function by executing the above processing.

Therefore, in the mobile communication network according to the present invention, the mobile device 1 executes the mobile device location processing shown in the flowcharts of FIGS. 2 and 3. In this case, it is assumed that the mobile device 1 stores the perch channel number of the base station that also supports the packet switching function that was previously in the area.
The mobile station location process shown in the flowcharts of FIGS. 2 and 3 will be described. When the power is turned on or when the timer is activated, the mobile station location process is started. It is determined whether or not. Here, if it is determined that the power is turned on or normal standby, the process proceeds to step S2, and it is determined whether or not the currently located cell also supports the packet switching function. In this case, it is determined whether or not the packet switching function is supported from the broadcast information message of the broadcast channel transmitted by the base station of the cell in which the cell is located. Here, if it is determined that the cell that is in the area supports the packet switching function, the process branches to step S9 and the current cell that supports the packet switching function is directly in the area. In this way, the mobile station location process ends.

  If it is determined in step S2 that the cell located in the area does not support the packet switching function, the process proceeds to step S3 where the perch channel number n is set to 1 and stored in step S4. The carrier power level at the first perch channel number “1” is detected. Next, it is determined whether or not the level detected in step S5 is within the packet waiting permission level difference. Here, if the detected level is within the packet waiting permission level difference, the process branches to step S10 to be located in a cell that supports the packet switching function corresponding to the perch channel number. A specific example will be described. It is assumed that the mobile device 1 shown in FIG. 1 has been in the cell B, for example, and the mobile device 1 stores at least the perch channel of the cell B. Therefore, the carrier power level in the perch channel of the stored cell B is detected when the mobile device 1 is powered on or in normal standby after the end of communication. At this time, since the mobile device 1 is located at the periphery of the cell B as shown in FIG. 1, a sufficient level within the packet waiting permission level difference is obtained although it is slightly smaller than the level of the cell A. Thereby, the mobile device 1 can be located in the cell B. In this way, the mobile device 1 can immediately reach the cell B that also supports the packet switching function with a little processing time, and can efficiently select the circuit switched bearer 3a or the packet bearer 3b. Data communication can be performed.

  If it is determined that the detected level of the perch channel set in step S5 is not within the packet waiting permission level difference, the process proceeds to step S6 and the last channel in which the set perch channel is stored. It is determined whether or not. Here, since n = 1 is set, it is determined that it is not the last channel, and the process proceeds to step S7, where n is incremented by 1, and the perch channel number n is set as the number of the next perch channel. Then, returning to step S4, the process of searching for a cell that supports the above-described packet switching function is repeatedly performed. In this process, if it is determined that the level detected in any one of the perch channel numbers incremented sequentially is within the packet waiting permission level difference, the process branches to step S10 to execute the packet switching function corresponding to the perch channel number. The mobile station location processing ends when the mobile station is in the supported cell. If it is determined that the detected level is not within the packet waiting permission level difference even after processing up to the last stored perch channel number, the process branches from step S6 to step S11 to switch the packet exchange in the area. Being located in an unsupported cell of functionality. In this way, since the perch channel of the support cell of the packet switching function that has been in the previous area is scanned, the mobile device 1 spends a little processing time without giving the user a sense of incongruity, The probability of being in a cell that also supports the packet switching function can be increased.

By the way, when it is determined in step S1 that it is not the normal standby time, the process proceeds to step S8, where it is determined whether or not the user requests to start data communication. If it is determined that the data communication activation request has not been made, the process returns to step S1 and waits for normal waiting or until the data communication activation request is generated.
If it is determined in step S8 that the user has requested to start data communication, the process proceeds to step S12 shown in FIG. In step S12, it is determined whether or not the cell currently located also supports the packet switching function. In this case, it is determined whether or not the packet switching function is supported from the broadcast information message of the broadcast channel transmitted by the base station of the cell in which the cell is located. Here, if it is determined that the cell that is in the area supports the packet switching function, the process branches to step S18 and the current cell that supports the packet switching function is directly in the area. In this way, the mobile station location process ends.

    In addition, when it is determined in step S12 that the cell located in the area does not support the packet switching function or supports the packet switching function but is a packet restricted cell in which the use of the packet bearer is restricted, In step S13, a timer is started. Next, in step S14, the perch channel number is scanned to search for a cell that supports the packet switching function within the packet waiting permission level difference, and it is determined in step S15 whether or not the corresponding cell has been searched. . If it is determined that a cell that supports the packet switching function within the packet waiting permission level difference can be searched, the process branches to step S19 to reach the searched cell that supports the packet switching function. To do. Then, the mobile station location processing ends.

  Specifically, as shown in FIG. 1, it is assumed that the mobile device 1 is located in the cell A and the user operates a data communication activation request button in the mobile device 1. In this case, since the cell A does not support the packet switching function, the mobile device 1 scans the perch channel, receives the perch channel in the cell B, and detects the carrier power level. At this time, since the mobile device 1 is located at the periphery of the cell B as shown in FIG. 1, a sufficient level within the packet waiting permission level difference is obtained although it is slightly smaller than the level of the cell A. Further, it can be recognized from the broadcast information message of the broadcast channel that the cell B supports the packet switching function, and as a result, the mobile device 1 can be located in the cell B. As a result, the mobile device 1 can be located in the cell B that also supports the packet switching function with a little processing time, and selects the circuit-switched bearer 3a or the packet bearer 3b to efficiently perform data transmission. Communication can be performed.

  If it is determined in step S15 that the search has failed, it is determined in step S16 whether or not the timer time has expired, and the processes in steps S14 and S15 are repeated until the timer time expires. Then, if the timer time has expired without branching to step S19, the process proceeds to step S17 to be located in an unsupported cell of the packet switching function located. Then, the mobile station location processing ends. When the mobile station location processing is completed, the data communication requested by the user to start is started, and, for example, mail transmission processing, reception processing, or web access is performed. As described above, when a data communication activation request is made, a search for a cell that supports the packet switching function is performed only during the timer period, so that the mobile device 1 has a packet switching function without giving the user a sense of incongruity. It is possible to perform processing for staying in a supported cell.

  In this way, the mobile station 1 can be located in a cell that supports the packet switching function as well as the circuit switching function as much as possible. Returning to FIG. 1, the base station 2 and the base station 3 are connected to an MSC (Mobile Switching Center) 4. The MSC 4 is an exchange that relays the bearer exchanges of the SMSC 5, DAS 7, and PMSC 9 and the base stations 2, 3,. The SMSC (Short Message Service Center) 5 is a short message exchange that supports the short message bearer. When the MMTA (Mobile Message Transfer Agent) 10 receives a mail, it creates a notification for notifying the arrival of the mail. The SMSSC 5 relays the notification and transmits it via the MSC 4 and the base station 3 to the mobile device 1 that is a mail partner, for example, located in the cell B. The MMTA 10 is a mail receiving server that receives mail, and stores short messages from other mobile devices and mail data of E-mails sent from the Internet 13 in a mailbox (MSS) 11. The DAS (Direct Access System) 7 is an exchange that supports a circuit-switched bearer. For example, when communicating with the mobile station 1 located in the cell B using the circuit-switched bearer, the mobile station 1-base Connected via the route of the station 3-MSC4-DAS7. In this case, the nodes are mutually connected by the circuit switching bearer in the mobile device 1, the base station 3, the MSC 4 and the DAS 7.

  A PMSC (Packet Mobile Switching Center) 9 is an exchange that supports a packet bearer. For example, when data communication is performed using a packet bearer with a mobile station 1 located in a cell B, the mobile station 1-base It is connected by the route of the station 3-MSC4-PMSC9. In this case, the nodes are mutually connected by packet bearers in the mobile device 1, the base station 3, the MSC 4, and the DAS 7. An MMAP (Mobile Message Access Protocol) 6 to which the SMSC 5, the DAS 7 and the PMSC 9 are connected is a mail transmission server to the mobile device, and the mail data stored in the mail box 11 when the mail reception request from the mobile device is requested. 1 is distributed. A WGW (Web Gateway System) 8 is disposed between the DAS 7 and the PMSC 9 and the Internet 13, and serves as a gateway between the mobile communication network protocol and the Internet protocol. It is possible to receive various services.

  For example, the mobile device 1 can acquire Internet content on the mobile device 1 by designating the address of the content on the Internet 13 by a URL (Uniform Resource Locator). The size of the content in this case is limited to 20 kByte, and the content with higher expressiveness can be downloaded to the mobile device 1. In addition, relatively small-capacity data can be acquired in a short time by acquiring content using a packet bearer. Further, by downloading a Java (registered trademark: TM) application program to the mobile device 1, various applications including games can be downloaded. When the mobile device is turned on for the first time, it is automatically connected to a mobile station information agent (MSIA) 12 and the initial setting of the mobile device is automatically performed by downloading control information from the MSIA 12. . In one of these initial settings, a file size threshold is set. When the mobile device downloads a file having a size up to the threshold, the packet bearer is selected and connected, and when the threshold is exceeded, the circuit switched bearer is selected and connected. Therefore, the MSIA 12 can be freely performed for each mobile device by changing the distribution of use between the packet bearer and the circuit switched bearer to a threshold value of an arbitrary value. In this case, it is preferable to determine the threshold value so that the use frequency of the packet bearer and the circuit switched bearer is optimized by looking at the overall communication status of the mobile communication network.

Next, when the mobile station 1 is located in the cell B that supports the packet switching function in addition to the circuit switching function, the mobile station 1 executes the mobile station location processing shown in FIGS. A bearer selection method according to the present invention will be described.
When the bearer used by the mobile device 1 is selected, the bearer is efficiently selected according to the state of the cell in the area and the type of the activated application. Hereinafter, a case where mail is handled and a case where access is made using HTTP (Hypertext Transfer Protocol) will be described in detail.

1. Mail The bearer used by the mobile device 1 when receiving the mail uses the bearer notified by the notification that notifies the mobile device 1 of the mail application or mail arrival in principle. For example, the mobile device 1 checks the bearer control field when receiving the notification, and receives the received mail by preferentially using the bearer specified in the bearer control field. An overview of the data structure of Notification is shown in FIG. As shown in this figure, Notification consists of a User Information Data Block and an LS6 Information Data Block, and a bearer control field (Bearer Control) is defined in the EMMTP that constitutes a part of the User Information Data Block. When connection with the bearer specified in this bearer control field fails (outside packet switching network, packet switching is being restricted, ARQ (Automatic Repeat reQuest) activation failure), a screen for reconnection is prepared on the user interface. ing.

  When the user requests reconnection from this screen, the other bearer not used last time is used for connection. The next bearer to be used when no reconnection is requested is the bearer notified by Notification. ARQ is control in which, when an error is detected on the receiving side, a retransmission request is sent to the transmitting side so that the data in which the error has occurred is transmitted again. Note that the priority bearer set at the time of shipment from the factory of the mobile device 1 is a circuit-switched bearer (DAS) when sending mail to the mail receiving server MMTA 10, and mail is sent from the mail sending server MMAP6. The connection for reception is a packet bearer.

An operation when using the set priority bearer will be described below.
1.1 Mail transmission: packet bearer priority When sending mail by connecting to MMTA 10, if priority is given to connecting by packet bearer by the mail application, mail is sent to MMTA 10 using the packet bearer. . In general, since the size of mail is not so large, it is possible to efficiently send mail by using a packet bearer. The sequence in this case is shown in FIG. In the sequence using the packet bearer shown in FIG. 10, when starting mail transmission, the mobile station (MS) 1 notifies the mobile communication network that the packet bearer is used by the packet channel. Thereby, a packet channel for data communication between the mobile device 1 and the PMSC 9 is registered (Packet Channel Registration). Next, a connection by TCP (Transmission Control Protocol) between the mobile device 1 as one end and the MMTA 10 as the other end is established (TCP Connection Open).

  As a result, the mobile station 1 and the PMSC 9 are ready to transmit mail using the packet bearer, and the mail packetized from the mobile station 1 using the packet bearer is transmitted to the base station 3 and the MSC 4. Is sent to PMSC 9 via. The PMSC 9 transmits the mail to the MMTA 10 that is a mail receiving server. When the MMTA 10 receives the mail normally, the MMTA 10 notifies the completion of the mail transmission (Mail Submit Complete). This notification is sent to the mobile device 1 via the PMSC 9, MSC 4, and base station 3. When the mobile device 1 receives this notification, the TCP connection with the MMTA 10 is released (TCP Connection Close), and the packet channel between the mobile device 1 and the PMSC 9 is released (Packet Channel Release). Thereby, the mail transmission using the packet bearer is completed.

  Here, FIG. 4 shows a connection model shown in the protocol hierarchy between the mobile station (MS) 1 and the mail receiving server MMTA 10 when mail is transmitted in the sequence using the packet bearer shown in FIG. In the protocol hierarchy of the mobile device (MS) 1, the circuit-switched bearer 1a, the packet bearer 1b, and the SMS bearer 1c corresponding to the data link layer in the OSI (Open Systems Interconnection) reference model are the lowest layer, and the layer above it is An IP (Internet Protocol) layer 1d corresponding to the network layer in the OSI reference model is used, and a layer above it is a TCP layer 1e corresponding to the transport layer in the OSI reference model. The layers above the TCP layer 1e are SMTP (Simple Mail Transfer Protocol) for mail transmission and MMAP (Mobile IMAP4 rev1) protocol for mail reception that are used for transferring electronic mail on the Internet. This SMTP + MMAP1f corresponds to the session layer, presentation layer, and application layer in the OSI reference model. Note that the SMS bearer is a bearer used by the SMSC 5 to notify the mobile device of Notification or to transmit / receive a short message.

  The base station (BS) 3 and the MSC 4 include circuit-switched bearers 3a and 4a, packet bearers 3b and 4b, and SMS bearers 3c and 4c corresponding to the data link layer, respectively. Further, the PMSC 9 includes a packet bearer 9a corresponding to the data link layer and an Ethernet LAN (Local Area Network) interface 9b. In the MMTA 10 which is a mail receiving server, the LAN interface 10a corresponding to the data link layer is the lowest layer, the layer above it is the IP (Internet Protocol) layer 10b corresponding to the network layer, and the layer above it is the trans The TCP layer 10c corresponds to the port layer. The layer above the TCP layer 10c is a protocol SMTP 10d used for mail transfer.

  By the way, the data link layer, which is a packet bearer, circuit-switched bearer, or LAN interface, is a layer that transfers information between adjacent nodes as shown in FIG. 4, and exchanges control information and exchanges data. It is considered as a layer. That is, data is transferred from the mobile device 1 to the MMTA 10 using this data link layer. The IP layer, which is the network layer, controls the route between the mobile device 1 and the MMTA 10, and the communication path between the mobile device 1 and the MMTA 10 is determined by the network layer. Furthermore, in the TCP layer, which is a transport layer, a logical communication path between the mobile device 1 and the MMTA 10 is formed, and whether the mobile device 1 and the MMTA 10 are apparently connected by a single line. It becomes like this. Furthermore, in the SMTP layer corresponding to the session layer, the presentation layer, and the application layer, communication rules between the mobile device 1 and the MMTA 10 and the data format are defined, and application matching is achieved. The Mailer 1g in the hierarchy of the mobile device 1 is a mail application that can send and receive mail.

  In the example shown in FIG. 4, when the mobile device 1 transmits a mail using a packet bearer to the MMTA 10 that is a mail receiving server, the base station 3 and the base station 3 are connected between the mobile device 1 and the base station (BS) 3. The MSC 4 and the MSC 4 and the PMSC 9 are connected by a packet bearer, and the PMSC 9 and the MMTA 10 are connected by a LAN such as Ethernet. As a result, a route between the mobile device 1 and the MMTA 10 is established, and the TCP layer 1e in the mobile device 1 and the TCP layer 6c in the MMTA 10 are connected by a logical communication path. As a result, when mail is transmitted by the SMTP 1g in the mobile device 1, this mail can be received by the SMTP 10d of the MMTA 10.

1.2 Mail transmission: circuit-switched bearer (DAS) priority When connecting to the MMTA 10 and sending mail, if priority is given to connection with the circuit-switched bearer (DAS) by the mail application, the circuit-switched bearer (DAS) Send mail to MMTA 10 using DAS). In this case, a large size mail can be efficiently transmitted. The sequence in this case is shown in FIG. In the sequence using the circuit-switched bearer shown in FIG. 11, when mail transmission is started, a communication channel occupied between the mobile device (MS) 1 and the DAS 7 is set, and the mobile device (MS) 1 A line to DAS 7 is established (Call Establish). Next, a TCP connection is established between the mobile device 1 as one end and the MMTA 10 as the other end (TCP Connection Open).

  As a result, the mail is ready to be transmitted using the circuit switched bearer, and the mail packetized from the mobile station 1 using the circuit switched bearer is sent to the DAS 7 via the base station 3 and the MSC 4. Sent. The DAS 7 transmits the mail to the MMTA 10 that is a mail receiving server. When the MMTA 10 receives the mail normally, the MMTA 10 notifies the completion of the mail transmission (Mail Submit Complete). This notification is sent to the mobile device 1 via the DAS 7, the MSC 4, and the base station 3. When the mobile device 1 receives this notification, the TCP connection with the MMTA 10 is released (TCP Connection Close), and the communication channel set between the mobile device 1 and the DAS 7 is released (Call Release). Thereby, the mail transmission using the circuit switched bearer is completed.

Here, FIG. 5 shows a connection model shown in the protocol hierarchy between the mobile station (MS) 1 and the mail receiving server MMTA 10 when mail is transmitted in the sequence using the circuit-switched bearer shown in FIG. The connection model shown in FIG. 5 is different from the connection model shown in FIG. 4 only in a configuration using a circuit switched bearer instead of a packet bearer, and this configuration will be described.
In the example shown in FIG. 5, the DAS 7 includes a circuit switched bearer 7a and a LAN interface 7b. When the mobile device 1 transmits a mail to the MMTA 10 that is a mail receiving server using a circuit switching bearer, the mobile device 1 is connected between the base station (BS) 3, the base station 3 and the MSC 4, and the MSC 4. And DAS7 are connected by circuit-switched bearers 1a, 3a, 4a and 7a which are data link layers, and DAS7 and MMTA10 are connected by LAN I / Fs 7b and 10a such as Ethernet. As a result, the route between the mobile device 1 and the MMTA 10 is determined, and the TCP layer 1e in the mobile device 1 and the TCP layer 10c in the MMTA 10 are connected by a logical communication path. As a result, when mail is transmitted by the SMTP 1g in the mobile device 1, this mail can be received by the SMTP 10d of the MMTA 10.

1.3 Mail reception: packet bearer priority When a priority is given to the bearer used when the mobile station 1 receives a mail when connection with the packet bearer is prioritized by the mail application or Notification, the packet bearer is used in principle. . However, packet bearers and circuit-switched bearers are used properly under the following conditions. If the number of time slots that can be used in the packet channel indicated by the broadcast information transmitted from the base station is 3 time slots in a cell that supports the packet switching function, connection is made using a packet bearer. To do. Further, even when the number of time slots that can be used in the packet channel indicated by the broadcast information is 2 time slots, connection is made using a packet bearer. When the number of time slots that can be used in the packet channel indicated by the broadcast information is one time slot, connection is made using a circuit-switched bearer because the transmission speed is limited. However, when the command to the transmission server (MMAP6) is DELETE or ALLDELTE, the command is transmitted by connecting with a packet bearer. Furthermore, when it is located outside the area that supports the packet switching function or when connection using a packet bearer is restricted, connection is performed using a circuit switching bearer.

Next, FIG. 13 shows a sequence for connection using a packet bearer.
In the sequence using the packet bearer shown in FIG. 13, when mail is received by the MMTA 10, the mail receiving server MMTA 10 creates a notification for notifying the arrival of the mail, and the SMSSC 5 relays the notification to relay the SMS bearer. It is transmitted to the mobile device 1 which is a mail destination via the MSC 4 and the base station 3. At the same time, the MMTA 10 stores the mail data in the MSS 11. The mobile device 1 recognizes that an incoming mail has been received, and when the user performs an operation to receive the mail, the mobile device 1 notifies the mobile communication network that the packet bearer is used through the packet channel. Thereby, a packet channel to be used is registered between the mobile device 1 and the PMSC 9 (Packet Channel Registration). Next, a connection by TCP (Transmission Control Protocol) between the mobile device 1 as one end and the MMAP 6 as the other end is established (TCP Connection Open). As a result, the TCP layer of the mobile device 1 and the TCP layer of the MMAP 6 are connected, and preparation for receiving mail using the packet bearer is completed.

  Then, a GET command for obtaining mail from the mobile device 1 using a packet bearer is transmitted to the PMSC 9 via the base station 3 and the MSC 4. The PMSC 9 transmits the GET command to the MMAP 6 that is a mail transmission server. Upon receiving this GET command, the MMAP 6 reads mail data addressed to the mobile device 1 from the MSS 11 and sends it to the PMSC 9. The PMSC 9 sends this mail data to the mobile device 1 via the MSC 4 and the base station 3 using the packet bearer. As a result, the mobile device 1 can acquire the mail and transmits a G-ACK signal notifying that the mail has been received to the PMSC 9 via the base station 3 and the MSC 4. The PMSC 9 transmits the G-ACK signal to the MMAP 6 that is a mail transmission server. When the MMAP 6 receives this G-ACK signal, the TCP connection between the MMAP 6 and the mobile device 1 is released (TCP Connection Close), and the packet channel between the mobile device 1 and the PMSC 9 is released (Packet Channel Release). Thereby, the mail reception using the packet bearer is completed.

Here, FIG. 6 shows a connection model shown in the protocol layer between the mobile station (MS) 1 and the mail transmission server MMAP 6 when receiving mail in the sequence using the packet bearer shown in FIG.
As shown in FIG. 6, in the MMAP 6 as a mail transmission server, the LAN interface 6a corresponding to the data link layer is the lowest layer, the layer above it is the IP (Internet Protocol) layer 6b, and the layer above it is The TCP layer 6c corresponds to the transport layer. The layer above the TCP layer 6d is a protocol MMAP6d that is an extension of the mail receiving protocol IMAP (Internet Messaging Access Protocol) for mobile use.

  By the way, the data link layer, which is a packet bearer, circuit-switched bearer or LAN interface, is a layer for transferring information between adjacent nodes as shown in FIG. 6, and exchanges control information and exchanges data. It is considered as a layer. That is, data is transferred between the mobile device 1 and the MMAP 6 using this data link layer. The IP layer, which is the network layer, controls the route between the mobile device 1 and the MMAP 6, and the communication path between the mobile device 1 and the MMAP 6 is determined by the network layer. Further, in the TCP layer as a transport layer, a logical communication path between the mobile device 1 and the MMAP 6 is formed, and the mobile device 1 and the MMAP 6 are apparently connected by a single line. It becomes like this. Furthermore, in the MMAP layer corresponding to the session layer, the presentation layer, and the application layer, communication rules between the mobile device 1 and the MMAP 6 and the data format are defined, and application matching is achieved.

  In the example shown in FIG. 4, when the mobile device 1 receives a mail from the MMAP 6 that is a mail transmission server using a packet bearer, the mobile station 1 and the base station (BS) 3, The MSC 4 and the MSC 4 and the PMSC 9 are connected by a packet bearer as a data link layer, and the PMSC 9 and the MMAP 6 are connected by a LAN I / F such as Ethernet. As a result, the route between the mobile device 1 and the MMAP 6 is determined, and the TCP layer 1e in the mobile device 1 and the TCP layer 6c in the MMAP 6 are connected by a logical communication path. As a result, the mail transmitted from the MMAP 6d in the MMAP 6 is received by the MMAP 1f in the mobile device 1.

1.4 Mail reception: packet bearer forced When mobile station 1 receives mail, it is forcibly connected with a packet bearer. In this case, the packet bearer is used for connection regardless of the number of time slots that can be used in the packet channel indicated by the broadcast information transmitted from the base station. The connection sequence using the packet bearer in this case is the same as the sequence shown in FIG. 13, and the connection model between the mobile station (MS) 1 and the MMAP 6 which is the mail transmission server shown in the protocol layer is also described in 1.3. It becomes the same as the connection model shown in FIG.

1.5 Mail reception: circuit-switched bearer priority The bearer used when the mobile station 1 receives mail is a circuit-switched bearer when it is given priority to connect with a circuit-switched bearer by a mail application or Notification. To do. FIG. 14 shows a connection sequence using a circuit-switched bearer in this case.
In the sequence using the circuit-switched bearer shown in FIG. 14, when mail is received by the MMTA 10, the mail receiving server MMTA 10 creates a notification for notifying the arrival of the mail, and the SMSSC 5 relays the notification to the SMS bearer. It is transmitted to the mobile device 1 which is a mail destination via the MSC 4 and the base station 3. At the same time, the MMTA 10 stores the mail data in the MSS 11.

  The mobile device 1 recognizes that a mail has been received, and when the user performs an operation to receive the mail, the communication channel occupied between the mobile device (MS) 1 and the DAS 7 is set, and the mobile device 1 moves. A line between the machine (MS) 1 and the DAS 7 is established (Call Establish). Next, a connection by TCP (Transmission Control Protocol) between the mobile device 1 as one end and the MMAP 6 as the other end is established (TCP Connection Open). As a result, the TCP layer of the mobile device 1 and the TCP layer of the MMAP 6 are connected, and it is ready to receive mail using the circuit-switched bearer.

  Then, a GET command for obtaining mail from the mobile device 1 using a circuit-switched bearer is transmitted to the DAS 7 via the base station 3 and the MSC 4. The DAS 7 transmits the GET command to the MMAP 6 that is a mail transmission server. Upon receiving this GET command, the MMAP 6 reads mail data addressed to the mobile device 1 from the MSS 11 and sends it to the DAS 7. The DAS 7 sends this mail data to the mobile device 1 via the MSC 4 and the base station 3 using a circuit switching bearer. Thereby, the mobile device 1 can acquire the mail, and transmits a G-ACK signal notifying that it has been received to the DAS 7 via the base station 3 and the MSC 4. The DAS 7 transmits the G-ACK signal to the MMAP 6 that is a mail transmission server. When the MMAP 6 receives this G-ACK signal, the TCP connection between the MMAP 6 and the mobile device 1 is released (TCP Connection Close), and the communication channel set between the mobile device 1 and the DAS 7 is released (Packet Channel). Release). This completes the mail reception using the circuit-switched bearer.

Here, FIG. 7 shows a connection model shown in the protocol hierarchy between the mobile station (MS) 1 and the mail transmission server MMAP 6 when receiving mail in the sequence using the circuit-switched bearer shown in FIG. In the connection model shown in FIG. 7, the only configuration different from the connection model shown in FIG. 6 is a configuration using a circuit switched bearer instead of the packet bearer, and this configuration will be described.
As shown in FIG. 7, the DAS 7 includes a circuit switched bearer 7a and a LAN interface 7b. When the mobile device 1 receives mail from the MMAP 6 as a mail transmission server using a circuit-switched bearer, the mobile device 1 moves between the DAS 7 and the MSC 4, the MSC 4 and the base station 3, and the base station (BS) 3. The device 1 is connected by circuit-switched bearers 7a, 4a, 3a, and 1a, which are data link layers, and the DAS 7 and the MMAP 6 are connected by a LAN I / F such as Ethernet. As a result, the route between the mobile device 1 and the MMAP 6 is determined, and the TCP layer 1e in the mobile device 1 and the TCP layer 6c in the MMAP 6 are connected by a logical communication path. As a result, the mail transmitted by the MMAP 6d in the MMAP 6 is received by the MMAP 1f in the mobile device 1.

2. HTTP
The HTTP related access to the WWW (World Wide Web) on the Internet basically uses a packet bearer. In addition, the Java ^TM application program is composed of a JAR file which is a program body whose compression format is JAR (Java ARchive) and a JAD (Java Application Descriptor) file including information on the JAR file. When downloading a file using HTTP, a file size threshold is determined for each number of time slots that can be used in packet switching, and either a packet bearer or a circuit switched bearer is determined based on the file size and the number of packet time slots. Select. In this case, when downloading a file with a size up to the threshold value for each time slot number, select and connect the packet bearer, and select the circuit switched bearer when the threshold value for each time slot number is exceeded. Connecting. The file size threshold defined for each time slot number of 1 to 3 time slots is set based on control information acquired from a mobile station information agent (MSIA) 12. The MSIA 12 is automatically connected when the mobile device is turned on for the first time, and the initial setting of the mobile device is automatically performed by downloading the control information. In addition, when any bearer is designated by an upper layer (Markup Language or the like), the designated bearer is preferentially connected.

Here, FIG. 8 shows a connection model shown in the protocol hierarchy between the mobile device (MS) 1 and the Web server 14 when the mobile device 1 accesses the Web server 14 on the Internet 13 using a packet bearer. In the protocol hierarchy of the mobile device (MS) 1, the circuit-switched bearer 1a, the packet bearer 1b, and the SMS bearer 1c corresponding to the data link layer in the OSI (Open Systems Interconnection) reference model are the lowest layer, and the layer above it is An IP (Internet Protocol) layer 1d corresponding to the network layer in the OSI reference model is used, and a layer above it is a TCP layer 1e corresponding to the transport layer in the OSI reference model. The layer above the TCP layer 1e is HTTP1h which is a protocol for transferring information between a server and a client on the Internet, Java1j which provides an execution environment for markup languages XHTML1i and Java ^TM which are extended for mobile use. ing. The HTTP 1h, XHTML 1i, and Java 1j correspond to the session layer, presentation layer, and application layer in the OSI reference model.

  The base station 3 and the MSC 4 include circuit-switched bearers 3a and 4a, packet bearers 3b and 4b, and SMS bearers 3c and 4c corresponding to the data link layer, respectively. Furthermore, the PMSC 9 includes a packet bearer 9a and a LAN interface 9b corresponding to the data link layer. The WGW 8 serving as a gateway between the mobile communication network protocol and the Internet protocol includes a LAN interface 8a corresponding to a data link layer. The WGW 8 is connected to the Web server 14 on the Internet 13 shown in FIG. 1 by a LAN I / F 8a. In this Web server 14, the LAN interface 14a corresponding to the data link layer is the lowest layer, the upper layer is the IP layer 14c corresponding to the network layer, and the upper layer is the TCP layer corresponding to the transport layer. It is set as the layer 14d. An HTTP layer 14e is located on the TCP layer 14d.

In the example shown in FIG. 8, when the mobile device 1 uses the packet bearer 1b to access the Web server 14 using the HTTP 1h as an upper protocol, the base station 3 is connected between the mobile device 1 and the base station (BS) 3. And MSC4, MSC4 and PMSC9 are connected by packet bearers 1b, 3b, 4b, and 9a, between PMSC9 and WGW8, and between WGW8 and Web server 14 are LAN I / F9b such as Ethernet, Connected by 8a and 14a. Thereby, the route between the mobile device 1 and the Web server 14 is determined, and the TCP layer 1e in the mobile device 1 and the TCP layer 14d of the Web server 14 are connected by a logical communication path. It becomes like this. As a result, the mobile device 1 can access the Web server 14 using HTTP and download a file or the like described in XHTML. The downloaded file is displayed on the display by the browser 1k which is an application. Further, a JAR file such as a game can be downloaded from the Web server 14 by accessing the Web server 14. The JAR file constituting the Java ^™ application program 1m such as the downloaded game can be executed on the Java ^™ execution environment 1j, and the downloaded game can be played on the mobile device 1. When accessing the Web server 14 using a packet bearer, a small size file can be efficiently downloaded.

Next, FIG. 9 shows a connection model shown in the protocol hierarchy between the mobile device (MS) 1 and the Web server 14 when the mobile device 1 accesses the Web server 14 on the Internet 13 using a circuit switching bearer. . In this case, the configuration different from the connection model shown in FIG. 8 is only the configuration using a circuit switched bearer instead of the packet bearer, so this configuration will be described.
In FIG. 9, the DAS 7 includes a circuit switching bearer 7a and a LAN interface 7b. When the mobile device 1 accesses the Web server 14 on the Internet 13, the data link is between the mobile device 1 and the base station (BS) 3, between the base station 3 and the MSC 4, and between the MSC 4 and the DAS 7. Layer-switched bearers 1a, 3a, 4a, and 7a are connected, and DAS 7 and PMSC 9 and WGW 8 are connected, and WGW 8 and Web server 14 are connected by LAN I / Fs 7b, 8a, and 14a such as Ethernet. .

Thereby, the route between the mobile device 1 and the Web server 14 is determined, and the TCP layer 1e in the mobile device 1 and the TCP layer 14d of the Web server 14 are connected by a logical communication path. It becomes like this. As a result, the mobile device 1 can access the Web server 14 using HTTP and download a JAR file such as a file described in XHTML or a game from the Web server 14. The downloaded file is displayed on the display by the browser 1k which is an application. In addition, a JAR file constituting the Java ^™ application program 1m such as a downloaded game can be executed on the Java ^™ execution environment 1j, and the downloaded game can be played on the mobile device 1. Note that when a circuit-switched bearer is used for downloading, a large-sized JAR file or the like can be downloaded efficiently.

Flow charts of bearer selection processing executed by the mobile device 1 to which the bearer selection method according to the present invention described above is applied are shown in FIGS. The flowcharts shown in FIGS. 15 to 18 will be briefly described.
In the mobile device 1, when an event related to data communication occurs, the bearer selection process in the flowcharts shown in FIGS. 15 to 18 is activated, and it is determined in step S21 whether the event is an email transmission event. Here, if it is determined that the event is a mail transmission event, it is determined whether or not priority is given to branching to step S30 and connecting with a packet bearer. In this case, if priority is given to connection by a packet bearer by the mail application, the process proceeds to step S31 and a packet channel for communication between the mobile device 1 and the PMSC 9 using the packet bearer is registered. Next, in step S32, a TCP connection between the mobile device 1 and the MMTA 10 is established, and preparations for transmitting mail data from the mobile device 1 to the MMTA 10 using a packet bearer are completed.

  Therefore, mail data is transmitted from the mobile device 1 to the MMTA 10 in step S33. In this case, the packet bearer transmits the mail data to the MMTA 10 using the registered packet channel. When receiving a mail transmission completion notification from the MMTA 10, the mobile device 1 determines that the mail transmission is completed in step S34, closes the TCP connection in step S35, and cancels the registered packet channel in step S36. To do. As a result, the mail transmission process using the packet bearer is completed, and the process returns to step S21 to wait for the next event. Step S34 is a process waiting until a mail transmission completion notification is received from the MMTA 10.

  If it is determined in step 30 that the packet bearer is not prioritized, it is determined by the mail application that priority is given to connection by a circuit-switched bearer (DAS), and the process branches to step S37. In step S37, a circuit-switching channel occupied by the circuit-switching bearer is set between the mobile device 1 and the DAS 7, a circuit is established, and preparations for mail transmission from the mobile device 1 to the MMTA 10 using the circuit-switching bearer are made. It ’s in place.

  Therefore, mail data is transmitted from the mobile device 1 to the MMTA 10 in step S39. In this case, the circuit-switched bearer transmits mail data to the MMTA 10 using the set circuit-switched channel. Upon receiving a mail transmission completion notification from the MMTA 10, the mobile device 1 determines that the mail transmission is completed in step S40, closes the TCP connection in step S41, and releases the circuit switching channel in step S42. . As a result, the mail transmission process using the circuit-switched bearer is completed, and the process returns to step S21 to wait for the next event. Step S40 is a process of waiting until a mail transmission completion notification is received from the MMTA 10.

  Next, when it is determined that the event generated in step S21 is not mail transmission, the process proceeds to step S22, and it is determined whether or not the event is a notification reception event for notifying mail arrival. Here, if it is determined that the notification of incoming mail has been received, the process branches to step S50 shown in FIG. 16 and waits until the user performs an operation of receiving the mail notified of incoming mail. Here, when the user performs an operation of receiving the mail notified of the incoming call, it is determined in step S51 whether or not priority is given to connection by the packet bearer by the mail application or Notification. In this case, if it is determined that the connection by the packet bearer is prioritized, the process proceeds to step S52 to determine whether the forced connection is set by the packet bearer.

  If the packet bearer forced connection is set, the process jumps to step S54 so as to receive mail using the packet bearer. If the packet bearer forced connection is not set, the process proceeds to step S53. It is determined whether or not the number of time slots (TS) that can be used in packet switching notified in (2) is two or more time slots. In this case, if the number of time slots (TS) is 2 time slots or more, the process proceeds to step S54 so as to receive mail using the packet bearer. In step S54, a packet channel for communication using the packet bearer between the mobile device 1 and the PMSC 9 is registered. Next, in step S55, the TCP connection between the mobile device 1 and the MMAP 6 is established, and the mobile device 1 is ready to receive mail from the MMAP 6 using the packet bearer.

  Therefore, in step S56, the mobile device 1 transmits a mail reception request GET command. Upon receiving this GET command, the MMAP 6 reads the corresponding mail data from the MSS 11 and passes it to the PMSC 9. The PMSC 9 transmits this mail data to the mobile device 1 using a packet bearer. The packet bearer transmits mail to the mobile device 1 using the registered packet channel. As a result, the mobile device 1 receives mail data (step S57). The mobile device 1 that has received the mail transmits a G-ACK signal notifying that it has been received to the PMSC 9, and the PMSC 9 transmits the G-ACK signal to the MMAP 6. When the MMAP 6 receives this G-ACK signal, the TCP connection between the MMAP 6 and the mobile device 1 is released in step S59, and further, the packet channel registered in step S54 is released in step S60. As a result, the mail receiving process using the packet bearer is completed, and the process returns to step S21 and waits for an event.

  If it is determined in step S51 that the use of a packet bearer is not specified by Notification, it is determined that the use of a circuit switched bearer is specified, and the process branches to step S61. In step S61, it is determined whether or not the mail reception operation operated in step S50 is an ALLDELETE or DELETE operation of the mail stored in the MSS 11. In this case, if the operation is not ALLDELETE or DELETE, the process proceeds to step S 62, the circuit switching channel occupied by the circuit switching bearer is set between the mobile device 1 and DAS 7, and the circuit between the mobile device 1 and DAS 7. Is established. Next, in step S63, a TCP connection is established between the mobile device 1 as one end and the MMAP 6 as the other end. As a result, the mobile device 1 is ready to receive mail from the MMAP 6 using the circuit-switched bearer.

    Therefore, in step S64, the mobile device 1 transmits a GET command for mail reception request. Upon receiving this GET command, the MMAP 6 reads the corresponding mail data from the MSS 11 and passes it to the DAS 7. The DAS 7 transmits this mail data to the mobile device 1 using a circuit switching bearer. The circuit-switched bearer transmits mail data to the mobile device 1 using the set circuit-switching channel. As a result, the mobile device 1 receives mail data (step S65). The mobile device 1 that has received the mail transmits a G-ACK signal notifying that it has been received to the DAS 7, and the DAS 7 transmits the G-ACK signal to the MMAP 6. When the MMAP 6 receives this G-ACK signal, the TCP connection between the MMAP 6 and the mobile device 1 is released in step S67, and the circuit switching channel set in step S62 is released in step S68. As a result, the mail reception process using the circuit-switched bearer ends, and the process returns to step S21 to wait for the next event.

  If it is determined in step S61 that the operation is ALLDELETE or DELETE, the process jumps to step S80 shown in FIG. 17 and the specified mail stored in the MSS 11 is deleted. In this deletion process, an ALLDELETE or DELETE command is transmitted using a packet bearer. Therefore, in step S80, a packet channel for communication using the packet bearer is registered between the mobile device 1 and the PMSC 9. Next, a TCP connection between the mobile device 1 and the MMAP 6 is established in step S81. Therefore, in step S82, the mobile device 1 transmits an ALLDELETE or DELETE command for a mail deletion request to the MMAP 6 using a packet bearer.

  Upon receiving this ALLDELETE or DELETE command, the MMAP 6 deletes the corresponding mail data from the MSS 11 (in the case of ALLDELETE, all are deleted). Next, the TCP connection between the MMAP 6 and the mobile device 1 is released in step S83, and the packet channel between the mobile device 1 and the PMSC 9 is released in step S84. Further, when the MMAP 6 completes the mail deletion, the MMAP 6 notifies the SMSC 5 of a deletion completion notification. The SMSC 5 notifies the mobile device 1 of the deletion completion notification using the SMS bearer. As a result, the mail deletion process using the packet bearer ends, and the process returns to step S21 to wait for the next event.

  Next, if it is determined that the event that occurred in step S21 is not mail transmission, and if it is determined in step S22 that the event is not reception of notification of mail arrival, the process proceeds to step S23. It is determined whether it is a web access event. If it is determined that the event is a web access event, the process branches to step S70 shown in FIG. Since web access is performed using a packet bearer, a packet channel for communication using the packet bearer is registered between the mobile device 1 and the PMSC 9 in step S70. Next, in step S71, a TCP connection is established between the mobile device 1 and the Web server 14 indicated by the URL. Therefore, in step S72, the mobile device 1 accesses the Web server 14 by HTTP, and displays the acquired file described in XHTML on the display.

When a file such as a Java ^TM application program can be downloaded from the Web server 14, the specified file can be downloaded from the Web server 14 to the mobile device 1. Therefore, in step S73, it is determined whether or not the designated file download operation has been performed by viewing the display on the display unit in the mobile device 1. Here, when the operation is not performed, it progresses to step S74 and it is determined whether the web connection termination operation was performed. When the web connection termination operation is performed, the TCP connection between the web server 14 and the mobile device 1 is canceled in step S75, and the packet channel set between the mobile device 1 and the PMSC 9 is also stepped. It is released at S76. As a result, the web access process using the packet bearer ends, and the process returns to step S21 to wait for the next event. Note that, when the web connection termination operation is not performed, the processes of step S73 and step S74 are repeatedly performed until the web connection termination operation is performed.

  If it is determined in step S73 that a download operation has been performed, the process branches to step S90 shown in FIG. In step S90, it is determined whether or not the size of the file to be downloaded exceeds the threshold acquired from the MSIA 12. If it is determined that the file does not exceed the threshold, the process proceeds to step S91. This threshold value is a file size threshold value determined for each number of time slots that can be used in packet switching. In step S91, it is determined whether or not the number of time slots that can be used in the packet exchange notified by the broadcast information is 2 or more. Here, when the notified number of time slots is 2 or more, the process proceeds to step S92 where the packet bearer is used and the specified file is downloaded from the Web server 14 to the mobile device 1 by HTTP.

  In step S93, the process waits until the download is completed. When the download is completed, the TCP connection between the Web server 14 and the mobile device 1 is released in step S94, and the mobile device 1 and the PMSC 9 are further disconnected in step S95. The configured packet channel is released. Thereby, the download process using the packet bearer ends, and the process returns to step S21 to wait for the next event. Note that when downloading is completed, the process may return to step S73 so that a plurality of files can be downloaded.

  If it is determined in step S90 that the size of the file to be downloaded exceeds the threshold acquired from the MSIA 12, and if it is determined in step S91 that the number of usable time slots is 1 by packet exchange Then, the process branches to step S96 to download the file by circuit switching. In step S96, the TCP connection between the Web server 14 and the mobile device 1 is released, and in step S97, the packet channel set between the mobile device 1 and the PMSC 9 is released. Subsequently, a circuit switching channel occupied by the circuit switching bearer is set between the mobile device 1 and the DAS 7 in step S98, and a circuit between the mobile device 1 and the DAS 7 is established. Next, in step S99, a TCP connection is established between the mobile device 1 as one end and the Web server 14 as the other end.

  In step S100, the specified file is downloaded from the Web server 14 to the mobile device 1 by HTTP using a circuit switching bearer. In step S101, the process waits until the download is completed. When the download is completed, the TCP connection between the Web server 14 and the mobile device 1 is released in step S102, and further, in step S103, between the mobile device 1 and the DAS 7. The configured circuit switching channel is released. As a result, the download process using the circuit-switched bearer ends, and the process returns to step S21 to wait for the next event. Note that when downloading is completed, the process may return to step S73 so that a plurality of files can be downloaded.

Here, an additional description will be given when downloading the Java ^™ application program to the mobile device.
The Java ^™ application program is composed of one JAD (Java Application Descriptor) file and one corresponding JAR (Java Archive) file. A JAD file is a text file that shows information (attributes) about the corresponding JAR file or Java ^TM application program, and includes information such as the application name and version, the URL that indicates the location of the JAR file, and the size of the JAR file. It is. The JAD file is used by an application manager (AM) to manage Java ^™ application programs. The application manager verifies whether or not the Java ^™ application program is suitable for the common Java ^™ execution environment before downloading the Java ^™ application program file (JAR file) using the information of the JAD file. The JAR file is a compressed or uncompressed binary file used to execute the Java ^™ application program. JAR file is manifest file, all the class files used by the Java ^TM application programs, including a resource file used by Java ^TM application programs (image, sound, etc.).

When downloading a Java ^™ application program, it is utilized that the Java ^™ application program is composed of a header part (JAD file) and an application body (JAR file) centered on attribute information. A mobile device that downloads a Java ^™ application program calls network information indicating a network state stored in a built-in nonvolatile memory from the mobile device, and performs bearer selection according to the network information. The network information is information related to HTTP, such as download size information such as a JAR file for the number of time slots usable in the packet channel indicated by the broadcast information transmitted from the base station.

The basic download procedure for downloading the Java ^™ application program is shown below.
1. The mobile device starts the browser from the standby state and enters the browser mode.
2. A Web site where the Java ^™ application program is anchored is accessed from the main menu displayed on the screen acquired using HTTP. That is, by selecting on the browser a desired Java ^™ application program to be anchored to the Web site (by the <A> tag or the like) by a user operation, from the Web server of the URL specified by the anchor, the Java A JAD file related to the ^TM application program is downloaded. In this case, when the browser mode is a persistent connection, the JAD file is downloaded by a TCP transaction continued from the browser mode. If the browser mode is not a persistent connection, a TCP connection is established when a JAD file download request is made, and the JAD file is downloaded by the transaction. Also, the bearer when downloading the JAD file is the bearer selected in the process after the Web access process (step S23) in the bearer selection process shown in FIG. 15 to FIG.

3. The mobile device calls a JAD file analysis function provided from the common Java ^™ execution environment after the download of the JAD file from the anchor destination URL specified by the user is completed. The common Java ^™ execution environment checks the content (attribute value) of the JAD file in the JAD file analysis function, and returns the result (normal / abnormal) to the platform of the mobile device as a return value.

4). The platform of the mobile device notifies the user of the download confirmation screen only when the result of the JAD file analysis function provided by the common Java ^TM execution environment is normal, and the user agrees to it (press “OK”) ) Start downloading the JAR file. If the return value is abnormal, the user is notified of this.
When downloading a JAR file, check the value of the JAR file size information (MIDlet-Jar-Size) set in the JAD file and compare it with the threshold value reported as network information from the MSIA. When the value of the JAR file size exceeds the threshold value, the JAR file acquisition process is performed using a circuit-switched bearer (special DAS) having a line number different from the general line number. The download source is a URL indicating the location of the JAR file obtained by analyzing the JAD file, that is, a download proxy server (Java Proxy) for the Java ^™ application program.

If the value of the JAR file size is equal to or smaller than the threshold value, a packet bearer is selected, and the JAR file is downloaded from the proxy server (Java Proxy) using the packet bearer. However, if the network environment in which the mobile device exists does not support the packet bearer, the JAR file is downloaded using the circuit-switched bearer even if the value of the JAR file size is equal to or smaller than the threshold value.
The threshold will be further described. A JAR file size threshold is determined for each number of time slots usable in packet switching, and either a packet bearer or a circuit switched bearer is selected based on the file size and the number of packet time slots. In this case, when downloading a JAR file having a size up to the threshold value for each time slot number, a packet bearer is selected and connected, and when the threshold value for each time slot number is exceeded, a circuit switched bearer is selected. Connect. The threshold of the JAR file size defined for each time slot number of 1 to 3 time slots is set based on control information acquired from a mobile station information agent (MSIA) 12. If the size of the Java ^™ application program exceeds the downloadable size, the user is notified that the download is not possible.

5). After receiving the JAR file, the mobile station platform analyzes the JAR file (manifest file). If there is an error at this time, an error message such as “Failed to acquire Java ^™ application” is displayed, the acquired JAD file or JAR file is deleted, and the browser state is restored. Further, when the analysis result of the JAR file (manifest file) is normal and the Java ^™ application program is immediately activated Java ^™ application (MIDlet-Immediate: Y), the downloaded Java ^™ application is immediately activated. If it is not immediately activated, the Java ^™ application program is saved in the memory in the mobile device or in the external memory according to the save attribute (MIDlet-Save) of the JAD file.
Whether or not the application is an immediately activated Java ^™ application can be obtained by analyzing the MIDlet-Immediate information of the JAD file. Further, when the Java ^™ application program is saved, if the free space of the memory in the mobile device or the external memory is insufficient, the user is notified that it cannot be saved.

6). The JAR file saved in the internal memory or the external memory of the mobile device can be selected by the user from the Java ^™ selector of the mobile device, and the selected Java ^™ application program is started to start the selected Java file. ^TM applications (eg, games) can be executed.
7). When the execution of the Java ^™ application is finished and the storage in the memory is completed, the mobile device returns to the browser state.

If there is an incoming call while downloading the Java ^™ application program, the download is temporarily stopped and resumed when the incoming call ends. Further, it is possible to determine whether the Java ^™ application program is a content that harms public order and morals by determining whether or not the content has been authenticated using the MIDlet-Code of the JAD file. Further, it may be determined that downloading is not possible when there is no free space in the memory for storing the Java ^™ application program. Furthermore, it is determined whether or not the Java ^™ application program is a content that cannot be saved or transferred, and processing for saving and transferring the Java ^™ application program that is prohibited from being saved or transferred is prohibited. Each of these controls is a control that can be performed based on attribute information in the JAD file.

By the way, when the mobile device is downloading the Java ^™ application program, if the mobile device receives an incoming call, the download is temporarily stopped. Further, when the mobile device moves out of service area during downloading, the physical line is disconnected. In such a case, when the incoming call is finished and the communication is ready, the Java ^TM application program is downloaded again from the beginning. It was a cause of increased congestion and user stress. Therefore, in the mobile station according to the present invention, and can be acquired only missing parts that were not downloaded again used rather than obtaining Java ^TM application program from the beginning, the byte range features available .

The byte range function refers to requesting one or more byte ranges that could not be received in the entity instead of the entire entity when reception of the entity was not completed due to moving to an out-of-service area during response reception. It is a function that can. In this case, the byte range that can be specified is in units of 1 byte. Send Range header when using byte range request function. For specifying the entity, the Range header is used in combination with the If-Range header. Therefore, when an unexpected network disconnection occurs during downloading of the Java ^TM application program, by using such a byte range function, all of the Java ^TM application program is not acquired again. Only missing parts can be acquired. In this case, the download file is analyzed by specifying the shortage compared to the analysis of the download file at the time of line disconnection and the download size of the JAD file. This makes it possible to effectively use radio network resources and reduce access time. In particular, it is possible to improve efficiency when re-downloading at the time of failure recovery.

  As described above, the present invention stores the perch channel number of the packet support area and selects the standby channel based on the perch channel number, so that the mobile communication terminal is located in the packet support area as much as possible. Can be made. As a result, the mobile communication terminal can expand the range of bearer selection and enable efficient bearer selection.

  In addition, when a mail is received, the bearer specified by the notification information is used preferentially, or the bearer specified by the mail application is preferentially used when mail is transmitted. Furthermore, since the packet bearer is preferentially used when accessing the web, efficient bearer selection can be made for each application. Furthermore, efficient bearer selection can be made possible by selecting a bearer according to the number of usable time slots or selecting a bearer according to the size of a file to be loaded. By performing efficient bearer selection in this way, the performance of the mobile communication network is improved and a large number of users can be accommodated with fewer resources. Furthermore, the file size threshold information is set to an arbitrary value that can adjust the ratio of the use of the circuit switched bearer and the packet bearer in the mobile communication network, so that the circuit switching is performed in the mobile communication network. It becomes possible to adjust the rate at which bearers and packet bearers are used.

It is a figure which shows the outline | summary of a structure of the mobile communication network in embodiment of this invention which has the mobile communication terminal of this invention. It is a flowchart of a part of mobile station location process which the mobile station in the mobile communication network in embodiment of this invention performs. It is a flowchart with the remaining mobile device location process which the mobile device in the mobile communication network in embodiment of this invention performs. It is a figure which shows the connection model shown with the protocol hierarchy of the mobile apparatus and MMTA in the case of transmitting mail using a packet bearer in the mobile communication network concerning embodiment of this invention. It is a figure which shows the connection model shown with the protocol hierarchy of the mobile apparatus and MMTA in the case of transmitting mail using a circuit switching bearer in the mobile communication network concerning embodiment of this invention. It is a figure which shows the connection model shown with the protocol hierarchy of the mobile apparatus and MMAP in the case of receiving mail using a packet bearer in the mobile communication network concerning embodiment of this invention. It is a figure which shows the connection model shown with the protocol hierarchy of the mobile apparatus and MMAP in the case of transmitting mail using a circuit switching bearer in the mobile communication network concerning embodiment of this invention. It is a figure which shows the connection model shown with the protocol hierarchy of the mobile apparatus and web server in the case of performing web access using a packet bearer in the mobile communication network concerning embodiment of this invention. It is a figure which shows the connection model shown by the protocol hierarchy of the mobile apparatus and web server in the case of performing web access using a circuit switching bearer in the mobile communication network concerning embodiment of this invention. It is a figure which shows the sequence in the case of transmitting mail using a packet bearer in the mobile communication network concerning embodiment of this invention. It is a figure which shows the sequence in the case of transmitting a mail using a circuit switching bearer in the mobile communication network concerning embodiment of this invention. It is a figure which shows the data structure of Notification in the mobile communication network concerning embodiment of this invention. It is a figure which shows the sequence in the case of receiving mail using a packet bearer in the mobile communication network concerning embodiment of this invention. It is a figure which shows the sequence in the case of transmitting a mail using a circuit switching bearer in the mobile communication network concerning embodiment of this invention. It is a flowchart of a part of bearer selection process which the mobile apparatus in the mobile communication network in embodiment of this invention performs. It is a flowchart of a part of bearer selection process which the mobile apparatus in the mobile communication network in embodiment of this invention performs. It is a flowchart of a part of bearer selection process which the mobile apparatus in the mobile communication network in embodiment of this invention performs. It is a flowchart with which the bearer selection process which the mobile station in the mobile communication network in embodiment of this invention performs performs remains.

Explanation of symbols

1 mobile device, 1a circuit switching bearer, 1b packet bearer, 1c SMS bearer, 1d IP layer, 1e TCP layer, 1f SMTP + MMAP, 1g Mailer, 1h HTTP, 1i XHTML, 1j Java ^TM execution environment, 1k browser, 1m Java ^TM application Program, 2 base station, 2a circuit switched bearer, 3 base station, 3a circuit switched bearer, 3b packet bearer, 3c SMS bearer, 4 MSC, 5 SMSC, 6 MMAP, 6a LAN interface, 6b IP layer, 6c TCP layer, 7 DAS, 7a circuit switched bearer, 7b LAN interface, 8 WGW, 8a LAN interface, 9 PMSC, 9a packet bearer, 9b LAN interface, 10 MMTA, 10a LAN interface, 10b IP layer, 10c TCP layer, 11 mailbox Box, 13 Internet, 14 Web server, 14a LAN interface, 14c IP layer, 14d TCP layer, 14e HTTP layer, A cell, B cell

Claims (2)

A movement in which there is a first area that supports a circuit-switched bearer that performs communication by circuit switching, and a second area that supports both the circuit-switched bearer and a packet bearer that performs communication by packet switching A bearer selection method in a communication network,
When a mobile communication terminal located in the first area or the second area accesses the web, a file size threshold is set for each number of time slots that can be used in packet switching, and the mobile The communication terminal acquires the number of time slots that can be used by the broadcast information from the base station, and the size of the file to be loaded exceeds the threshold value of the file size determined by the acquired number of usable time slots. until with selecting a packet bearer, if it exceeds the threshold value selecting circuit switched bearer, a bearer selection method is characterized in that so as to access the web using the selected bearer. A movement in which there is a first area that supports a circuit-switched bearer that performs communication by circuit switching, and a second area that supports both the circuit-switched bearer and a packet bearer that performs communication by packet switching A mobile communication terminal in a communication network,
When accessing the web, a file size threshold is set for each number of time slots that can be used in packet switching, and the number of time slots that can be used is obtained from broadcast information from the base station. Select the packet bearer until the file size to be loaded exceeds the threshold for the file size threshold determined by the number of time slots, and select the circuit-switched bearer when the threshold is exceeded , A mobile communication terminal characterized in that a web is accessed using the selected bearer .

Images