JP3335070B2 - Communication terminal device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication terminal device such as a portable personal computer or a facsimile having an interface for wired communication and wireless communication.

[0002]

2. Description of the Related Art In recent years, portable communication terminals that can be easily carried have been actively researched and developed in the field of communications. Along with this, along with a wired communication interface for performing wired communication using a public line or a communication cable, a wireless communication interface for performing wireless communication using electromagnetic waves (radio waves) or light (infrared rays) has been developed. A communication system that enables communication even when moving with a communication terminal device equipped with these has been constructed. In the case of wired communication, fixed installation of the device is required, but the data communication speed is high and the speed is excellent, and the error rate in data communication is low and the reliability is excellent. In the case of wireless communication, although high speed and reliability are difficult, it is excellent in mobility such that communication can be performed while moving the device itself. Therefore, the user uses the interface properly according to the environment in which the communication terminal device is used, while considering the advantages and disadvantages of the wired communication and the wireless communication.

For example, Japanese Patent Application Laid-Open No. Hei 1-170261 discloses a telephone line interface unit, a car telephone interface unit, and a wireless interface unit. Is disclosed.

Japanese Patent Application Laid-Open No. 4-319467 discloses an interface for wired communication and an interface for wireless communication. When a communication cable is connected to the interface for wired communication, the communication is not hindered by wireless communication. There is disclosed a printing apparatus that performs wired communication.

[0005]

However, in a conventional communication terminal device having a plurality of types of communication interfaces, each communication interface functions independently with an independent address and a certain communication interface. When communication is performed with a communication terminal device or the like at the communication destination using the communication interface, the communication interface must be used from the start to the end of the communication (including the end due to an abnormality). It was not possible to switch the communication interface while maintaining communication.

[0006] When switching the communication interface, it is necessary to end the current communication and start the communication again using another communication interface. For example, a wired communication in which a communication terminal device is fixedly installed is required. When moving the communication terminal device in the middle, the communication is temporarily interrupted, so the communication contents at that time must be reconnected with the communication terminal device of the communication destination in order to communicate again through the wireless communication interface, Usability was poor.

SUMMARY OF THE INVENTION In view of the above, the present invention provides a communication terminal device capable of switching between a wired communication interface and a wireless communication interface without interrupting communication, and ensuring a good communication state when switching. The purpose is to provide.

[0008]

Means for Solving the Problems According to the present invention, there is provided a detecting means comprising a wired communication interface and a wireless communication interface, and detecting an interface usable for communication with a communication destination from the interfaces. And switching means for switching the interface between the available interfaces while continuing the communication with the communication destination, and the interface according to various conditions without interrupting the current communication. Can be switched smoothly.

Here, the detection of usable interfaces is performed by transmitting and receiving data to and from a communication destination through each interface. Further, the usable interface includes an interface under communication.

A communication line connection detecting means for detecting a connection state between the wired communication interface and the communication line is provided, and when the interface is switched in accordance with the change in the connection state, the current communication can be performed without interruption. The communication terminal device can be shifted between a fixed state in which communication is performed using the communication interface and a mobile state in which communication is performed using the wireless communication interface.

Further, if the communication destination has a plurality of interfaces and has a structure in which the interface used for communication can be easily switched, the interface can be used for communication with the communication destination by switching this interface. In some cases, the interface of the communication source that has become unavailable becomes unavailable. However, if the detection by the detection unit is performed at regular intervals, the available interface can be reliably grasped.

Further, a comparison means for comparing the communication capabilities of each of the usable interfaces is provided, and the interfaces are switched according to the communication capabilities. Here, the communication capability is a communication speed of each interface set in advance, an effective speed when actually used for communication with a communication destination detected during communication, and the like. An interface having a high communication capability is selected and switched among available interfaces according to a change in the connection state with the line, or an interface having a high communication capability is actively selected and switched regardless of the change in the connection state. be able to.

Further, storage means for storing connection information in communication with a communication destination of each interface is provided, and the interface is switched according to the connection information at the time of the next communication with the communication destination. Here, the connection information is information that can be used to determine the priority of each interface used for communication, such as information on whether or not access to the communication destination is possible at each interface obtained through communication with the communication destination, effective speed, and billing. . Therefore, it is not necessary to detect an available interface every time communication is performed with a communication destination, and transmission and reception of data between the communication destination and the communication destination for detection can be reduced.

Further, a data distribution means for distributing transmission data to an available interface is provided to perform transmission processing at a high speed, or at the time of transmission of confidential data, an available interface is sequentially or randomly switched to transmit data on a network. This makes it difficult to reconstruct the flowing confidential data by eavesdropping.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) FIG. 3 schematically shows a communication terminal device such as a portable personal computer according to a first embodiment of the present invention. This communication terminal device has a user interface with a user and has a communication function, and includes a terminal device 1 and a plurality of types of communication interfaces (communication interfaces) that can be connected to communication lines such as a public line and a network cable. Hereinafter, referred to as communication I / Fs # ₁ to _#n ) and an interface switching device (hereinafter, referred to as an I / F switching device) 2 for switching communication I / Fs # ₁ to _#n used for communication. The communication I / Fs # ₁ to _#n are connected to the terminal device 1 via the I / F switching device 2, and input / output of communication data is performed on the terminal device 1 through the communication I / Fs # ₁ to _#n. It has become. Also, the I / F switching device 2 has a communication I / F #
A communication line connection detection device (hereinafter, referred to as a cable attachment / detachment detection device) 3 for detecting a connection state between the wired communication interface and the communication line among ₁ to _#n is connected to the I / F.
The switching device 2 is configured to switch the communication I / Fs # ₁ to _#n while continuing the current communication according to the connection state.

Here, the configuration of the communication terminal device will be described in detail with reference to FIGS. As shown in FIG. 4, the terminal device 1 is configured such that a CPU 10 stores a program stored in a ROM 11 as an RA as a main storage device as a work area.
M12 is used to execute processing, and includes a display device 13 such as a liquid crystal display, an input device 14 such as a keyboard and a mouse, and a storage device 15 for storing processing contents.

The communication I / Fs # ₁ to _#n are LAN
A first interface (hereinafter, referred to as a wired I / F # ₁ ) 16 for wired communication connected to a network cable (for example, Ethernet), and wired communication connected to a public line via a modem or the like via a connection line. Interface (hereinafter, referred to as wired I / F # ₂ ) 17 and a wireless communication interface using radio waves (hereinafter, wireless I / F # ₂ ).
18). Wired I / F # ₂ 17 is connectable to the information processing apparatus 20 connected to the network cable by wire-wire connecting device 19 which is installed in the network cable via a public line, a wired I /
Communication with the information processing apparatus 20 by using the F # ₂ 17 is possible. Also, the antenna 1 from the wireless I / F 18
8a is received by the antenna 21a of the wireless / wired connection device 21 which mediates wireless and wired communication provided on the network cable, or the radio wave transmitted from the antenna 21a is transmitted by the antenna 21a. 18a
, Communication with the information processing device 20 using the wireless I / F 18 is enabled. Here, the maximum communication speed when using the I / F16,17,18 has a relationship wired I / F # ₁ 16> wireless I / F18> wired I / F # ₂ 17.

Each of the I / Fs 16, 17, and 18 has its own physical address and logical address on the network, and communicates with other communication terminal devices on the network by wire communication or wireless communication. Can be done. Incidentally, the logical address is usually I / O
This is an address set by the user to obtain a physical address unique to the F. Each I / F is based on the logical address.
16, 17, and 18 obtain unique physical addresses. Specifically, by adding the physical address of the communication source and the physical address of the specific communication destination to the packet sent on the network, the packet is transmitted between the communication source and the specific communication destination, and communication is possible. Becomes

As shown in FIG. 5, the I / F switching device 2 includes a switching device 30 such as a switching element for switching each of the I / Fs 16, 17, and 18, and a CPU for controlling the switching device 30.
31, RAM 32, ROM 33, the type of each of the connected I / Fs 16, 17, 18, the physical address, the logical address, the type of the protocol used, and each I / F 16, 1
Communication speed when using 7, 18 and each I / F 16, 1
A connection interface parameter table (connection I / F parameter table) 34 for storing static information such as whether or not there is a charge when using the devices 7 and 18, and a physical address of a communication destination when communication is actually performed; And a connection state table 35 that describes dynamic information such as the relationship between the logical address and the I / F used.

The I / F switching device 2 is connected to each I / F 1
The received packets received by the terminals 6, 17, and 18 and the transmission data transferred from the terminal device 1 are temporarily stored in the RAM 32,
The PU 31 is configured to execute a process of reconstructing a received packet stored in the ROM 33 into received data and a process of converting transmitted data into a transmitted packet.

The cable attachment / detachment detecting device 3 has a wired I / O
F # ₁ 16 and detects the detachment and wired I / F # ₂ 17 and attachment and detachment of the connecting line between the network cable a micro switch or optical sensor, the detection result (output signal) I / F switching device 2 To the CPU 31.

In the communication terminal device of the present embodiment, the CPU 31 of the I / F switching device 2
A switching function for detecting an I / F usable for communication with a specific communication destination among 6, 17 and 18, and a switch 30 in accordance with a change in an output signal from the cable detachment detection device 3; It has a switching function of switching from an I / F being used for communication with a specific communication destination to another available I / F while continuing the current communication.

Next, the operation of the communication terminal device having the above configuration when performing communication will be described with reference to FIGS. First, in with the communication terminal apparatus is fixedly installed state of connecting a network cable and wired I / F # ₁ 16, the wired I / F
# To start communication using ₁ 16, the output signal indicating that the wired I / F # ₁ 16 is connected by a cable detachment detection device 3 is input to the I / F switching device 2, information communication to processor 20 wired I / F # _{1 1}
6 to be set.

When this communication terminal device is accessed from the network, each I / F 16, 1
7 and 18 select and process only the packet to which the unique physical address is added. Here, the communication with a specific communication destination of the communication terminal apparatus using a wired I / F # ₁ 16 starts, I / F switching device 2, the communication destination physical address,
A logical address and a physical address of a communication source are newly created in the connection state table 35.

The I / F switching device 2 is a wireless I / F
18 and the physical address of the communication destination obtained through the wired I / F # ₁ 16 in order to detect whether or not access is possible with the communication terminal device of the communication destination currently communicating through the wired I / F # ₂ 17 To send a packet irrelevant to the communication content with the wireless I / F 18 added as the physical address of the communication source via the wireless I / F 18,
/ F # sends independent packets and communication content added with those wired I / F # ₂ 17 as the physical address of the communication source through ₂ 17, waits for a response from the communication destination of the communication terminal device for this. Then, the wireless I / F 18 and the wired I / F
F # is registered with a logical address and physical address of the communication destination results in the connection status table 35 for the answer from the communication terminal apparatus of the resulting communication destination through ₂ 17.
As a result, an I / F that can be used for communication with the communication terminal device at the communication destination can be detected.

[0026] Here, in the communication using a wired I / F # ₁ 16, when removed for the mobile communications terminal device a network cable from the wired I / F # ₁ 16, in the conventional wired communication I If a packet was transmitted through / F, the transmitted packet would be lost.
A retransmission request is returned from the communication terminal device at the communication destination. When a packet is received through the wired communication I / F, the received packet is lost. After switching to another available I / F, a retransmission request is sent to the communication terminal device of the communication destination. Will be sent.

[0027] In the communication terminal apparatus of this embodiment, the output signal indicating that the wired I / F # ₁ 16 is not connected by a cable detachment detection device 3 is input to the I / F switching device 2, I / F The switching device 2 has a connection state table 35.
Wireless I / F18 and wired I / F # ₂ 17 to determine whether it is possible to use as a replacement on the basis of the information described in.

Here, the wireless I / F 18 and the wired I / F
# ₂ If 17 are both available, the connection I / F on the basis of the information stored in the parameter table 34 employs a fast communication speed wireless I / F18, wired I / F #
Only packets when it was communicating through ₁ 16 to communicate with the physical address of the wired I / F # ₁ 16.
Thus, it is possible to switch while continuing the current communication from the wired I / F # ₁ 16 was in use to the radio I / F18 available.

In this case, communication via the wireless I / F 18 is performed by a communication terminal device accessing a physical address assigned as the wireless I / F 18 and a wired I / F # _1.
Permission is given to the communication terminal device of the specific communication destination that has been communicating through the communication terminal 16.

Also, the wireless I / F 18 cannot be used and the wired I / F 18
If / F # ₂ 17 is available, employ a wired I / F # ₂ 17, the physical address of the wired I / F # ₁ 16 wired only packets that were communicating through I / F # ₁ 16 Use to communicate. Further, the wireless I / F 18 and the wired I / F
If F # ₂ 17 are both disabled, terminal equipment 1
To the CPU 10 that communication cannot be performed.

[0031] While communicating through the wireless I / F18 and wired I / F # ₂ 17, to connect said network cables and wired I / F # ₁ 16 again, the wired I / F by the cable removal detection device 3 # output signal indicating that _{the 1} 16 is connected is input to the I / F switching device 2, I /
F switching device 2 transmits a packet to detect whether the current communication terminal of the communication destination is a communication carried out device and accessible through a wired I / F # ₁ 16, the communication of the communication destination hand If there is a response from the terminal, in use the wireless I / F18 or wired I / F # ₂ 17 wired I / F
# ₁ 16 is switched while continuing to communicate with the current communication destination of the communication terminal device, the connection uses the state table 35
Update.

Also, a wireless I / F 18 and a wired I / F #
₂ 17 or a both disabled, while termination or communication in a state in which the switch for communication through the wireless I / F18 and wired I / F # ₂ 17, again for communication through a wired I / F # ₁ 16 When the communication is completed in the switched state, each I / F 1 in the connection state table 35 used is changed.
Data such as access permission information necessary for the access of 6, 17, 18 is deleted.

[0033] In the above, the wired I / F # _{1 1}
Network cable during communication using
Has been described the operation of detaching from the F # ₁ 16, when removing the connection line in communication using a wired I / F # ₂ 17 from the wired I / F # ₂ 17 or FIG. 6,
While similarly continue the current communication when the wired I / F # ₁ 16 or a wired I / F # ₂ 17 is connected in communication using a wireless I / F18 as shown in 7 of other available I / F
Switch to

As described above, in the communication terminal device of the present embodiment, the I / F usable for communication with the communication destination is detected, and the change of the output signal from the cable attachment / detachment detection device 3, that is, the I / F for wired communication is detected. Since the current communication is switched from the I / F used for communication with the communication destination to the usable I / F according to the change in the connection state of the / F 16 and 18 with the communication line, the communication is performed. The terminal device is fixedly installed, and I /
In the case where the communication terminal device is moved to perform communication through the wireless communication I / F 17 while performing communication through F16 and F18, and vice versa, it is necessary to wait until the current communication ends as in the conventional case. There is no need to access the communication destination again through the I / F that has been given up or switched over by giving up the current communication, and it is possible to smoothly switch the I / F without interrupting the current communication,
Usability can be improved.

(Second Embodiment) In the communication terminal device according to the second embodiment, a timer 40 is provided in the I / F switching device 2 as shown in FIG. Then, the CPU 31 of the I / F switching device 2 detects the I / F that can be used for communication with a specific communication destination among the I / Fs 16, 17, and 18 for a predetermined time (a preset time N). ) Every time.

Therefore, as shown in FIG.
During communication using F # ₁ 16, the time T measured by the timer 40 becomes a preset set time N, the communication being currently communicating via the wireless I / F18 and wired I / F # ₂ 17 A packet for detecting whether or not the communication terminal device can access the communication terminal device is transmitted, and the wireless I / F 18 and the wired I / F 18 are transmitted.
Sequentially updates the result of the response from the communication terminal apparatus of the resulting communication destination through F # ₂ 17 in the connection state table 35. After that, the cable I / F
# Output _{signal 1} 16 indicates that it is not connected to I /
When the signal is input to the F switching device 2, the processing at the time of cable disconnection described in the first embodiment is performed. As a result, an I / F usable for communication with the communication terminal device at the communication destination can be detected at regular intervals. Other configurations and operations are the same as those of the first embodiment, and members having the same functions as those of the first embodiment are denoted by the same reference numerals.

Thus, if the communication terminal device of the communication destination also has a plurality of I / Fs and has a structure in which the I / F used for communication can be easily switched, this I / F is switched. The source I / F that was initially available for communication with the destination communication terminal may become unusable, but may be used for communication with the destination communication terminal at regular intervals. By detecting the I / F, the available I / F can be always grasped, the used I / F can be reliably switched to the usable I / F, and stable communication can be continued. Can be made more reliable.

(Third Embodiment) In the communication terminal device according to the third embodiment, the CPU 31 of the I / F switching device 2
Each I that can be used for communication with a communication terminal device of a specific communication destination
A comparison function for comparing the communication capabilities of the I / Fs 16, 17, and 18 is added, and the communication capability of the I / Fs 16, 17, and 18 that can be used according to the change in the output signal from the cable detachment detection device 3 is the highest. Switching is performed by selecting a high I / F. Here, the communication capability of each I / F 16, 17, 18 includes statistical data of the amount of error packets (appearance rate) when each of the I / Fs 16, 17, 18 is used for communication, and the I / F 16, 17, 18 Each of the I / Fs 16, 17, and 18 obtained from the response speed from when a packet is transmitted to the information processing device 20 to when it is received when the communication with the information processing device 20 is performed using the The effective speed when used for actual communication is targeted.

Then, as shown in FIG. 10, the wired I / F
# During communication using ₁ 16, the wireless I / F18 and wired I
/ F # ₂ 17 detects whether the current communication destination which communication communicating terminal apparatus and accessible through, monitors packets reaching each I / F17,18 of this time, the wireless I / F18 If or a wired I / F # ₂ 17 is accessible, sequentially stores the statistical data and the response speed of the incidence of error packets in the connection state table 35 as collected data of when using these communication.

[0040] Here, the output signal indicating that the wired I / F # ₁ 16 by the cable detachment detection device 3 is not connected is input to the I / F switching device 2, I / F switching device 2, wireless I / F18 and wired I / F # ₂ 17 based on the information described in the connection state table 35 to determine whether it is usable as an alternative, the wireless I / F18 and wired I / F # ₂ 17 if both available, the effective speed of each of the wireless I / F18 based on statistical data and the response speed of the incidence of error packets are described in the connection state table 35 wired I / F # ₂ 17 , And selects an I / F with a high effective speed capable of performing better communication with the communication destination, and uses the wired I / F # ₁₁ that has been used.
6 to the selected I / F while continuing the current communication. Thereafter, the processing at the end of communication described in the first embodiment is performed. Other configurations and operations are the same as those of the first embodiment, and members having the same functions as those of the first embodiment are denoted by the same reference numerals.

As a result, it is possible to switch to an I / F with a high effective speed suitable for the communication network condition and to secure a good communication state.

(Fourth Embodiment) In the communication terminal device according to the fourth embodiment, each of the I / Fs 16 and 1 that can be used regardless of a change in the output signal from the cable attachment / detachment detection device 3
Switching is performed by selecting an I / F having the highest communication capability from among 7, and 18.

Then, as shown in FIG. 11, the wired I / F
# During communication using ₁ 16, the wireless I / F18 and wired I
/ F # ₂ 17 detects whether the current communication terminal of the communication destination is a communication carried out device and accessible through, also statistical data and the response speed of the incidence of error packets in wired I / F # ₁ 16 It is sequentially stored in the connection state table 35 as collection data. Further, the wireless I / F18 and if wired I / F # ₂ 17 is available, the connection state table 3 statistics and response rate of incidence of error packets when using them to communicate as a collection data
Store sequentially in 5.

Here, the I / F switching device 2 performs the wireless I / F based on the information described in the connection state table 35.
18 and the wired I / F # ₂ 17 are determined as being usable as substitutes, and the wireless I / F 18 and the wired I / F # _{2 are determined.}
17 if both available, wired I / F # ₁ 16 based on the statistical data and the response speed of the incidence of error packets are described in the connection state table 35,
A wireless I / F18, and select the wired I / F # ₂ 17 Fast I / F of the effective rate by comparing the effective speed of each may perform communication with the communication destination better the wired was busy I / F
# Switch while continuing the current communication I / F which is selected from ₁ 16. When the communication is completed, the data described in the connection state table 35 is deleted. Note that other configurations and operations are the same as those of the third embodiment, and members having the same functions as those of the third embodiment are denoted by the same reference numerals.

As a result, it is possible to always switch to an I / F with a high effective speed suitable for the communication network condition, and to secure a good communication state.

(Fifth Embodiment) In the communication terminal device according to the fifth embodiment, the connection capability of each I / F
/ I stored in the / F parameter table 34
The communication speed when F is used is targeted.
The CPU 31 of the switching device 2 controls each of the available I / Fs 1 regardless of a change in the output signal from the cable attachment / detachment detection device 3.
The switching is performed by selecting an I / F having the highest communication capability among 6, 17, and 18.

Then, as shown in FIG. 12, the wired I / F
# During communication using ₁ 16, the wireless I / F18 and wired I
/ F # by detecting whether the current communication terminal of the communication destination is a communication carried out device and accessible through ₂ 17, connection I /
Wired I / O stored in the F parameter table 34
Comparing the communication speed in the communication speed and accessible I / F in F # ₁ 16, switched to the most communication speed which could fast speed transfer I / F. When communication ends,
The data described in the connection state table 35 is deleted. Note that other configurations and operations are the same as those of the third embodiment, and members having the same functions as those of the third embodiment are denoted by the same reference numerals.

As a result, it is possible to always select and switch an optimal I / F within a range of data stored in advance without requiring collection data such as statistical data of the appearance rate of error packets and response speed. .

(Sixth Embodiment) Even when the communication terminal device is moved, the location where the communication terminal device is used can be specified, the network configuration change is small, and the specific information processing device 20 serving as a reference at a specific I / F can be used. If the user can access the communication terminal device, the user sets a space on the network where the communication terminal device exists as an initial setting in the I / F switching device 2 so that the communication terminal device on this network and another I / F can access the device. By detecting whether the packet is transmitted or not, transmission of a packet irrelevant to communication contents on the network and response to the packet can be omitted.

Therefore, in the communication terminal device according to the sixth embodiment, as shown in FIG. 13, the I / F switching device 2 has a connection state selection table 50 that can determine the network space where the communication terminal device exists. And each I / F16,1
A connection state table storage device 51, which is storage means for storing connection information in communication with the communication terminal devices at the communication destinations 7 and 18, is provided, and the CPU 31 of the I / F switching device 2 is provided.
Detects whether the communication terminal device on the network set in the connection state selection table 50 and the I / F other than the in-use interface are accessible at the time of the next communication with the communication terminal device of the communication destination, If access is possible, switching of the I / F is performed according to the connection information stored in the connection state table storage device 51.

Here, the connection information refers to each I / F 16, 1
Access availability information with a specific communication destination in 7, 18;
This is information that can determine the priority of an I / F used for communication such as effective speed and charging.

When the power of the communication terminal device is turned on or when the output signal from the cable attachment / detachment detection device 3 changes, the operation of the communication terminal device on the network set in the connection state selection table 50 other than the busy state is not performed. I / F
Is detected whether or not it is accessible. At this time, if the communication destination has a previous access history, the connection information in each of the I / Fs 16, 17, and 18 stored in the connection state table storage device 51 is used as it is. I / O that is not in use, such as transmitting packets unrelated to the communication content
Without performing the access check of F, the connection information stored in the connection state table storage device 51 is copied to the connection state table 35, and the optimum I / F with the highest priority is selected according to the connection information. And switch.

If a certain period of time has passed since the connection information was stored in the connection state table storage device 51, that is, if the reliability in the previous access history is low, the I other than the in-use state is used. An access check of / F is performed to update the connection information. Then, at the end of the communication or when the output signal from the cable attachment / detachment detecting device 3 changes, the connection information of the used connection state table 35 is stored in a storage area of the connection state table storage device 51 corresponding to the network space. . Other configurations and operations are the same as those of the first embodiment, and members having the same functions as those of the first embodiment are denoted by the same reference numerals.

As a result, the I / F access check can be omitted as much as possible, and the optimum I / F can be selected and switched, and the switching of the I / F can be performed by reducing the traffic on the network and the time required for the switching. The processing can be speeded up.

(Seventh Embodiment) In the communication terminal device according to the seventh embodiment, as shown in FIG. 14, the I / F switching device 2 distributes transmission data to usable I / Fs. A transmission data distributor 60 as a dividing means is provided.

[0056] Then, in communication using a wired I / F # ₁ 16, whether the current communication terminal of the communication destination is a communication carried out device and accessible through a wireless I / F18 and wired I / F # ₂ 17 detects, distributor 60 includes a wired I / F # _{1 1} in use the transmission data temporarily stored in RAM32
6 are distributed according to the ratio of the communication speed described in the connection I / F parameter table 34 to the available I / Fs including the I / F 6. These transmission data are transmitted at once or sequentially from each available I / F via the switch 30.
The received data is received through a single I / F. Other configurations and operations are the same as those of the first embodiment, and members having the same functions as those of the first embodiment are denoted by the same reference numerals. Thus, transmission processing as a communication terminal device can be efficiently performed at high speed.

(Eighth Embodiment) In the communication terminal device according to the eighth embodiment, as shown in FIG. 15, a random number timing for causing the I / F switching device 2 to generate a timing for switching the I / F is provided. A generation device 70 is provided, and the CPU 31 of the I / F switching device 2 sequentially changes I / Fs that can be used by a confidential data transmission signal from an application used in the communication terminal device in accordance with the timing from the random number timing generation device 70. Or, they are switched randomly.

[0058] Then, the confidential during communication using a wired I / F # ₁ 16, when a situation requiring the steganographic that transmits confidential data for I / F switching device 2 from the application by sending a data transmission signal, sequentially or switched randomly according to the timing of the available I / F including the wired I / F # ₁ 16 from the random number timing generator 70, a confidential data multiple I / Send through F. Other configurations and operations are the same as those of the first embodiment, and members having the same functions as those of the first embodiment are denoted by the same reference numerals. This makes it difficult to reconstruct confidential data flowing on the network by eavesdropping as compared with a case where the data is transmitted through a single I / F, so that information confidentiality can be reliably performed.

The present invention is not limited to the above-described embodiment, and it goes without saying that many modifications and changes can be made to the above-described embodiment within the scope of the present invention. For example, an I / F equipped in a communication terminal device is a wired I / F #
₁ 16, the wired I / F # ₂ 17, not limited to the three types of wireless I / F18, or what kind if wired communication I / F and the wireless communication I / F.

[0060]

As is apparent from the above description, according to the present invention, it is possible to switch from an interface being used for communication with a communication destination to an available interface while continuing the current communication. There is no need to wait until the current communication ends, or to give up the current communication and access the communication destination again through the switched interface, and perform a smooth interface switch without interrupting the current communication be able to.

[0061] Since switching the interface depending on the change in the connection state between wired communication interface and the communication line, the mobile communication terminal device when it the communication terminal apparatus is fixedly installed is performing communication through a wired communication interface When communication is performed through the wireless communication interface and vice versa, the communication terminal can be switched between the fixed state and the mobile state without interrupting the current communication, and the usability can be improved. Improvement can be achieved.

[0062] Communication destination also includes a plurality of interfaces,
Moreover, if the interface used for communication can be easily switched, the interface of the communication source that was initially available for communication with the communication destination becomes unavailable by switching this interface. By detecting the interface that can be used for communication with the communication destination every time, the current available interface can be grasped, so that the interface can be switched reliably, and stable communication can be continued, Increases reliability.

[0063] Since it is possible to switch the interface in accordance with the communication capabilities of such effective speed when it is actually used for communication with the communication speed and the communication destination in each interface that has been set in advance For example, the communications network conditions By switching to an interface having a suitable high communication capability, a good communication state can be secured.

[0064] Since switching the interface depending on the connection information in each interface obtained in communication with the communications destination, it is not necessary to detect the interface available for every communication with the communication destination, for the detection The transmission and reception of data to and from the communication destination can be reduced, and the speed of the interface switching process can be increased by reducing the traffic on the network and the time required for switching.

[0065] Since distributed to feed interface available to transmit data, it is possible to efficiently perform transmission processing as a communication terminal apparatus at high speed.

[0066] Since sending sensitive data can interface a sequential or switch to randomly use, it becomes difficult as compared to when the reconstruction by eavesdropping on confidential data flowing over the network is sent through a single interface, steganographic Can be performed reliably.

[Brief description of the drawings]

FIG. 1 is a flowchart for switching a wired I / F # ₁ to another I / F in a communication terminal device according to a first embodiment of the present invention;

FIG. 2 is a flowchart when the wired I / F # ₁ is switched to another I / F.

FIG. 3 is a schematic block diagram of a communication terminal device.

FIG. 4 is a block diagram of a communication terminal device.

FIG. 5 is a block diagram of an I / F switching device.

FIG. 6 is a flowchart for switching a wireless I / F to another I / F.

FIG. 7 is a flowchart when the wireless I / F is switched to another I / F.

FIG. 8 is a diagram illustrating an example of a communication terminal device according to a second embodiment;
/ F switching device block diagram

FIG. 9 is a flowchart for switching an I / F.

FIG. 10 is a flowchart for switching an I / F in the communication terminal device according to the third embodiment.

FIG. 11 is a flowchart for switching an I / F in a communication terminal device according to a fourth embodiment.

FIG. 12 is a flowchart for switching an I / F in a communication terminal device according to a fifth embodiment.

FIG. 13 is a block diagram of an I / F switching device in a communication terminal device according to a sixth embodiment.

FIG. 14 is a block diagram of an I / F switching device in a communication terminal device according to a seventh embodiment.

FIG. 15 is a block diagram of an I / F switching device in a communication terminal device according to an eighth embodiment.

[Explanation of symbols]

2 I / F switching device 3 cable detachment detection device 16 wired I / F # ₁ 17 wired I / F # ₂ 18 radio I / F 51 connected state table storage device 60 transmits data distributor

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04L 29/04 G06F 13/00 353

Claims (7)

(57) [Claims] 1. A communication destination on a network is LA
Interface for wired communication to communicate through N
And a wired communication interface for communicating through a public line, and a wireless communication interface for performing wireless communication, and use a unique address to communicate with a communication destination.
A communication terminal device for performing communication of the communication terminal, detecting means for detecting an interface usable for communication with the communication destination from the interfaces, and continuing communication with the communication destination.
Other available interfaces from the current interface.
And switching means are provided for switching the interface, using
Use the address of the interface that was
A communication terminal device that performs communication through a changed interface . 2. A communication line connection detecting means for detecting a connection state between a wired communication interface and a communication line, wherein:
The switching unit is usable when the connection state changes.
Of the interfaces, the interface with the fastest communication speed
2. The communication terminal device according to claim 1, wherein the communication terminal is switched to a communication terminal. 3. A communication system comprising a plurality of interfaces for communication.
Structure that can switch the interface to be used
The available interface for the communication destination
The communication terminal device according to claim 1 , wherein the detection by the detection unit is performed at regular time intervals for grasping . 4. Communication of each available interface
Comparison means for comparing the effective speed is provided, and the switching means includes:
4. The communication terminal device according to claim 1, wherein the interface is switched to the interface having a higher effective speed . 5. Identification in a predetermined network space
Storage means for storing connection information of each interface in communication with another communication destination, and whether the connection information is stored.
Means for updating the connection information when a certain time has passed since
Doo is provided, the switching means, the communication terminal apparatus according to claim 1 or 2, wherein the switching the interface depending on the connection information during the next communication with the communication destination. 6. An interface capable of using transmission data.
Data distribution means for allocating data to each interface according to the ratio of the respective communication speeds.
Data transmitted from the
The claim 1, characterized in that it is received through the over scan
Is a communication terminal device according to 2 . At 7. A sensitive data transmission, switching means, the communication terminal apparatus according to claim 1 or 2, wherein the switching to sequentially or randomly available interfaces.