Abstract:
A communication method for enjoying service from a service providing system that provides predetermined service to a user after user authentication via a communication line and disconnects the communication line when the user authentication is not completed within a predetermined time is provided. The communication method includes the steps of: (a) activating operations of monitoring a communication state of the communication line and re-setting a communication parameter relating to communication when the communication state is degraded; and (b) suspending, during a predetermined time after the communication line is connected, at least one of the operations of monitoring the communication state and re-setting the communication parameter relating to the communication when the communication state is degraded.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to communication methods, communication apparatuses, software programs and computer-readable recording media, and more particularly to a communication method and communication apparatus that monitor line quality during communication and re-set communication parameters such as a communication rate and a modulation method according to need so as to ensure a stable communication state, and to a software program for causing a computer to carry out such communication, and to a computer-readable recording medium that stores such a software program.  
           [0003]    2. Description of the Related Art  
           [0004]    [0004]FIG. 1 shows a state where a terminal unit  10  on a user&#39;s side such as a personal computer is connected to a server  20  at an access point of an Internet service provider or the like via a communication line  30  such as a telephone line. The terminal unit  10  connectable to the communication line  30  as mentioned above is provided with a communication device that establishes connection to the communication line  30 , that is, a modem  11 . In order to ensure the stable communication state, the modem has functions of constantly monitoring the communication state and re-setting (, newly setting or updating) various communication parameters if necessary, such as a speed of circuit, communication protocol, error correction method and data compression method.  
           [0005]    According to the functions, normal communication is temporarily suspended and a communication parameter re-set operation (hereinafter referred to as a “re-set operation”) as described above is activated when, as a result of a monitoring operation as mentioned above, it is detected that an input signal level, a S/N ratio (signal-to-noise ratio) and the like drop to equal to or less than predetermined levels due to noise or the like on the communication line  30 . In other words, the operation of sequentially re-setting (, newly setting or updating) the various communication parameters is performed while negotiation between the modem  11  and a modem  21  of the server  20  is performed via the communication line  30 . In addition, as for noise, there are power noise, electromagnetic noise by a microwave and the like, and noise specific to an inverter of an air conditioner, for example.  
           [0006]    [0006]FIG. 2 is a function block diagram of the modem  11 . As shown in FIG. 2, the modem  11  includes a controller  11   a,  a modulator/demodulator  11   b  and a line interface part  11   c.  The controller  11   a  transmits/receives a signal to/from a personal computer (PC)  12 . The line interface part  11   c  is connected to the communication line  30  such as a telephone line and the like. The modulator/demodulator  11   b  is provided between the controller  11   a  and the line interface part  11   c.  The modulator/demodulator  11   b  has a function of converting the signal from the personal computer  12  to a signal for communication by compression and modulation. Additionally, the modulator/demodulator  11   b  has a function to convert the signal for communication received at the line interface part  11   c  to a signal that can be used in the personal computer  12  by demodulation and decompression.  
           [0007]    Further, generally, the functions of the controller  11   a  and modulator/demodulator  11   b  of the modem of today are realized by software, since the operation of a CPU in a computer is speeding up, for example. In this case, such software is called driver software. The driver software functions on the OS of a personal computer and carries out the modem functions as described above.  
           [0008]    In the system shown in FIG. 1, the Internet service provider performs a user authentication operation (hereinafter referred to as a “authentication operation”) in the beginning of the communication with a user, when providing, to the user, service according to the contract previously made with the user. In the authentication operation, the user is identified and authenticated by being prompted to input such as a user name and a user ID that are set when concluding the contract. After the identification and authentication of the user, the Internet service provider (hereinafter simply referred to as an “ISP”) connects the terminal unit  10  of the user to a communication network such as the Internet. The user can enjoy various services provided via the Internet only when the connection is established by the ISP after the authentication operation.  
           [0009]    [0009]FIG. 3 is a flow chart showing the operation in the above-described case. In step S 1 , a line connection operation by the modem  11  is started by a dial-up operation of application software (hereinafter simply referred to as an “application”) in the personal computer  12  as the terminal unit  10  on the user&#39;s side. Then, the modem  11  transmits a line connection request to the modem  21  provided to the server  20  at the access point of the ISP. As a result, in step S 2 , the negotiation between the modems  11  and  21  is performed. In step S 3 , whether or not the negotiation succeeds is determined. When the various communication parameters are set and the negotiation ends in success (YES in step S 3 ), the connection of the communication line  30  is completed in step S 5 .  
           [0010]    When the setting of the communication parameters by the negotiation ends in failure (NO in step S 3 ), the communication line  30  is disconnected in step S 4 , and the process is returned to the application again. Thereafter, steps S 1  through S 3  are repeated until the re-setting (, new setting or updating) of the communication parameters succeeds when the user gives a restart instruction.  
           [0011]    When the connection of the communication line  30  is completed in step S 5 , the process is handled by the application on the server  20  of the ISP from step S 6 . In step S 6 , the confirmation of the ID and a password is performed as the authentication operation. In step S 7 , whether or not the confirmation succeeds is determined. When the confirmation succeeds (YES in step S 7 ), the ISP connects the communication line  30  to a network in step S 8 . Consequently, in step S 9 , the user can enjoy the service via the network by Net-surfing and the like.  
           [0012]    However, when the re-setting operation is activated during the authentication operation in step S 6  due to noise or the like, the normal communication is stopped for performing the negotiation between the modems  11  and  21 . Accordingly, the authentication operation is aborted. As a result, the decision result in step S 7  is NO, and the process returns to the application on the user&#39;s side. When the user gives an instruction of restarting the connection with the communication line  30 , the communication line connection operation starting from step S 1  is started.  
           [0013]    [0013]FIGS. 4 and 5 show the operation flow that organizes the above-described operation and further includes the function of a authentication timer. First, FIG. 4 shows a case where the authentication succeeds without being aborted by the disconnection of the communication line  30  due to noise and the like. In this case, after a line connection operation (step S 21 ) and the completion of the line connection (step S 22 ), the authentication operation (step S 23 ) is started. At this moment, the authentication timer is activated in step S 24 . Then when the authentication operation is correctly carried out and ends in step S 25 , in step S 26 , the communication line  30  is connected to the network and the user can enjoy Net-surfing with the user terminal  10 . In this case, the authentication timer is cleared in step S 26 , by the completion of the authentication operation in step S 25 .  
           [0014]    Next, by referring to FIG. 5, a description will be given of a case where the authentication operation is aborted by the disconnection of the communication line  30  due to noise, and as a result, the authentication ends in failure. In this case, the operations from step S 21  to step S 23  are the same as those corresponding steps in FIG. 4. However, in FIG. 5, when the communication state is worsened due to noise and the like in step S 31 , the re-set operation is performed in step S 34  so as to recover the communication state. In this case, in order to perform the negotiation between the modems  11  and  21 , the normal communication is suspended in step S 32 . Consequently, the authentication operation cannot be continued and is aborted in step S 33 .  
           [0015]    Then, as a result of the re-set operation in step S 34 , the re-setting of the communication parameters is completed, the communication for the authentication operation is restarted, and the authentication operation is restarted. However, in this case, since the authentication operation is aborted in step S 33 , due to the passage of time, there is a case where the authentication timer times out before the authentication operation succeeds (step S 35 ). In this case, the authentication operation ends in failure (“failure in authentication”), and in step S 36 , the application on the server  20 &#39;s side disconnects the communication line  30  via the modem  21 . Thus, it is necessary for the user to reattempt from step S 21 , that is, the connection operation of the communication line  30 .  
           [0016]    For example, in a case where, since the state of the communication line  30  is wrong, due to noise and the like (step S 31 ), the “failure in authentication” because of the time out of the authentication timer (step S 35 ) and the disconnection of the communication line  30  (step S 36 ) caused by the “failure in authentication” is repeated more than once, the user cannot, for an indefinite period, enjoy the service via the network which service is a desired object.  
           [0017]    Next, referring to FIG. 6, a more detailed description will be given of the cause of the above-described situation. As shown in FIG. 6, when the line connection is completed in step S 41  (corresponding to step S 5  in FIG. 3, or in step S 22  in FIGS. 4 and 5), in step S 42 , the modem  11  on the user&#39;s side starts data transmission/reception with the modem  21  of the server  20  to which modem the communication line  30  is connected in step S 41 . Accordingly, in step S 61 , the application of the server  20  transmits a request for the ID and password as the authentication operation. In response, in step S 62 , the application on the user&#39;s side transmits the ID and password according to the input by the user.  
           [0018]    On the other hand, while the communication line  30  is connected (step S 43 ), when the communication state is temporarily degraded due to noise or the like in step S 44 , if a communication line monitor function is ON (YES in step S 45 ), the modem  11  detects the communication state. Further, if a re-set function is activated and effective (YES in step S 46 ), in step S 47 , the modem  11  suspends the general communication (data transmission/reception) for the re-set operation. It should be noted that, in step S 45 , it is determined whether or not the communication line monitor function is ON. In addition, whether or not the re-set function is ON is determined in step S 46 . Consequently, the authentication operation cannot be continued. Then, in step S 48 , the modem  11  performs the re-set operation of the communication parameters. As a result, the data transmission/reception is restarted in step S 49 , and the communication line  30  assumes a connected state in step S 50 . Accordingly, the authentication operation is restarted. When the authentication succeeds (YES in step S 64 ), the communication line  30  is connected to the network. However, when the authentication timer times out due to the delay in confirmation of the ID and password (step S 63 ) by the suspension of the authentication operation, the authentication ends in failure (NO in step S 64 ), and the communication line  30  itself is disconnected by the modem  21  of the ISP in step S 66 .  
         SUMMARY OF THE INVENTION  
         [0019]    It is a general object of the present invention to provide an improved and useful communication method, communication apparatus, software program and computer-readable recording medium by which the above-described problems are solved.  
           [0020]    It is a more specific object of the present invention to provide a communication method and communication apparatus that can achieve in a timely manner the desired object of the user without the delay of the authentication operation even when, during the authentication operation, the communication state is temporarily degraded due to the noise or the like, and to provide a software program for causing the computer to carry out such communication, and to provide a computer-readable recording medium that stores such a software program.  
           [0021]    In order to achieve the above-described objects, according to one aspect of the present invention, there is provided a communication method for enjoying service from a service providing system that provides predetermined service to a user after user authentication via a communication line and disconnects the communication line when the user authentication is not completed within a predetermined time, the communication method including the steps of: (a) activating operations of monitoring a communication state of the communication line and re-setting a communication parameter relating to communication when the communication state is degraded; and (b) suspending, during a predetermined time after the communication line is connected, at least one of the operations of monitoring the communication state and re-setting the communication parameter relating to the communication when the communication state is degraded.  
           [0022]    Also, according to another aspect of the present invention, there is provided a communication apparatus for enjoying service from a service providing system that provides predetermined service to a user after user authentication via a communication line and disconnects the communication line when the user authentication is not completed within a predetermined time, the communication apparatus including: a monitor that monitors a communication state of the communication line; an activating part that activates an operation of resetting a communication parameter relating to communication when the communication state is degraded; and a suspending part that suspends, during a predetermined time after the communication line is connected, at least one of functions of the monitor and the activating part.  
           [0023]    In addition, according to another aspect of the present invention, there is provided a software program for causing a computer to carry out a process for enjoying service from a service providing system that provides predetermined service to a user after user authentication via a communication line and disconnects the communication line when the user authentication is not completed within a predetermined time, the software program including the instructions of: (a) causing the computer to monitor a communication state of the communication line; (b) causing the computer to activate an operation of re-setting a communication parameter relating to communication when the communication state is degraded; and (c) causing the computer to suspend, during a predetermined time after the communication line is connected, at least one of monitoring the communication state of the communication line and activating the operation of re-setting the communication parameter relating to the communication when the communication state is degraded.  
           [0024]    Further, according to another aspect of the present invention, there is provided a computer-readable recording medium that stores the above-described software program.  
           [0025]    According to the present invention, having the authentication operation end in failure due to the suspension of communication (data communication) during the authentication operation is avoided. Thus, the authentication operation is performed smoothly. Therefore, it is possible for the user to promptly enjoy the service provided via the network which service is the desired object.  
           [0026]    Other objects, features and advantages of the present invention will become more apparent from the following detailed description when read in conjunction with the following drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0027]    [0027]FIG. 1 is a schematic diagram for explaining a construction in which service is provided via a communication line from a system that provides the service via a network, which construction is capable of embodying the present invention;  
         [0028]    [0028]FIG. 2 is a block diagram showing an example of the construction of a modem provided in a user terminal unit shown in FIG. 1;  
         [0029]    [0029]FIG. 3 is a flow chart for explaining the operation flow in which the user terminal unit is connected to a server that provides the service via the communication line, a user authentication operation is performed, and the user can enjoy the service via the network which service is a desired object;  
         [0030]    [0030]FIG. 4 is a flow chart (part  1 ) for arranging the operation flow in FIG. 3 and for explaining problems in prior art more specifically;  
         [0031]    [0031]FIG. 5 is another flow chart (part  2 ) for arranging the operation flow in FIG. 3 and for explaining the problems in the prior art more specifically;  
         [0032]    [0032]FIG. 6 is a flow chart for explaining the operations of a modem and an application in a separated manner which operations are especially associated with the present invention among the operations shown in FIGS. 3, 4 and  5 ;  
         [0033]    [0033]FIG. 7 is a block diagram showing the structure of a controller of the modem that serves as a communication apparatus according to a first embodiment of the present invention;  
         [0034]    [0034]FIG. 8A is a first half of a flow chart for explaining the operation flow of a communication method according to a second embodiment of the present invention;  
         [0035]    [0035]FIG. 8B is a latter half of the flow chart for explaining the operation flow of the communication method;  
         [0036]    [0036]FIG. 9 is a timing chart showing an example of the operation of the communication method according to the second embodiment of the present invention;  
         [0037]    [0037]FIG. 10 is a timing chart showing another example of the operation of the communication method;  
         [0038]    [0038]FIG. 11 is a flow chart for explaining the operations of the modem and the application in a separated manner which operations are especially characteristic of the operation in the communication method according to the second embodiment of the present invention; and  
         [0039]    [0039]FIG. 12 is a block diagram showing the structure of the user terminal according to a third embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0040]    A description will be given of embodiments of the present invention, by referring to the drawings.  
         [0041]    First, a description will be given of a communication apparatus according to the first embodiment of the present invention.  
         [0042]    In a construction similar to that shown in FIGS. 1 and 2 explained in “Background of the Invention”, basically, the communication apparatus according to the first embodiment of the present invention corresponds to the modem  11  of the user&#39;s side terminal unit  10  that is connected to the server  20  of the ISP via the communication line  30  and the like. Especially, the communication apparatus corresponds to the controller  11   a  in the modem  11 .  
         [0043]    [0043]FIG. 7 shows the construction of the controller  11   a  of the modem  11  as the communication apparatus according to the first embodiment of the present invention. As shown in FIG. 7, the communication apparatus includes a line connecting part  100 , a monitor (line quality monitor)  110 , and a re-setting part  120 . It should be noted that, as mentioned above, the function of the controller  11   a  is not only embodied in hardware, but may be embodied in a software program, that is, driver software.  
         [0044]    The line connecting part  100  performs the line connection operation by controlling the line interface part  11   c.  Further, the line connecting part  100  performs a data communication process between the terminal unit  10  and the sever  20 , by controlling the modulator/demodulator  11   b  to perform the modulation/demodulation, compression/decompression process and the like.  
         [0045]    The monitor  110  has a function of monitoring the communication state in the communication line  30 . In other words, the monitor  110  obtains, from the line interface part  11   c,  data relating to the communication state of the communication line  30  and analyzes the data so as to determine whether or not the communication state of the communication line  30  satisfies a predetermined level. Here, the communication state refers to a reception signal level, S/N ratio and the like. Then, when it is determined that the predetermined level is not satisfied, the monitor  110  notifies the re-setting part  120  of the determination result. The same notification is given also to the line connecting part  100 . Accordingly, the line connecting part  100  suspends the data communication that is currently in execution so as to prepare for the re-set operation. In the re-set operation, the communication parameters are re-set (, newly set or updated).  
         [0046]    When the re-setting part  120  receives, from the monitor  110 , the information indicating that the communication line  30  does not satisfy the predetermined level, the re-setting part  120  gives the line connecting part  100  an instruction to perform the re-set operation of the communication parameters. According to the instruction given by the re-setting part  120 , the line connecting part  100  performs the re-set operation of the various communication parameters by using the communication line  30 .  
         [0047]    In addition, the line connecting part  100  has a function of temporarily suspending the function of either the monitor  110  or the re-setting part  120  when a predetermined condition is met.  
         [0048]    Next, a description will be given of a communication method according to the second embodiment of the present invention.  
         [0049]    [0049]FIGS. 8A and 8B show a flow chart for explaining the operation of a communication method according to the second embodiment of the present invention. In FIG. 8A, the line connecting part  100  of the user&#39;s side modem  11  performs the line connection operation in step S 101 . Then, in step S 102 , the line connection is completed. At this moment, in step S 103 , the line connecting part  100  suspends the function of the monitor  110  or the resetting part  120 . At the same time, in step S 105 , the authentication timer is started. Thereafter, the authentication operation is performed by the application in step S 104 .  
         [0050]    Here, a case is assumed where the communication state is degraded at this moment due to noise or the like (step S 106 ). In this case, since the function of either the monitor  110  or the re-setting part  120  is suspended in step S 103 , the monitor  110  does not detect the degradation of the communication state, or the re-setting part  120  does not activate the re-set operation. Thus, since the suspension of the normal data communication following the activation of the re-set operation is not performed, the authentication operation is continued in step S 107 .  
         [0051]    In this manner, even if the degradation of the communication state occurs due to noise or the like, the authentication operation is continued. Therefore, the authentication is completed in step S 108 . As a result, in step S 110 , the function of either the monitor  110  or the re-setting part  120  that is suspended in step S 103  is reactivated. Then, the regular data communication is suspended in step S 111 . Only after step S 110 , the re-set operation due to the degradation of the communication state is activated in step S 112 . Then, by the re-set operation, when the re-setting (, newly setting or updating) is completed in step S 113  in FIG. 8B, the regular data communication is restarted in step S 114 . In step S 115 , it is possible for the user to perform Net-surfing or the like that is the desired object of the user, since the user terminal  10  is already connected to the network via the communication line  30  such as a telephone line and the like by the success of the authentication.  
         [0052]    It should be noted that even in steps S 111  through S 113 , that is, during the suspension of the communication following the re-set operation, the established communication line is maintained. Thus, the information authenticated in step S 108  is also maintained during the suspension. Therefore, when the data communication is restarted in step S 114 , it is not necessary to perform the authentication operation again, and it is possible to proceed to the operation of Net-surfing and the like that is the desired object.  
         [0053]    [0053]FIGS. 9 and 10 are timing charts for explaining the operation of the communication method according to the second embodiment of the present invention. FIG. 9 is the timing chart showing a case where the function of the re-setting part  120  is suspended until the completion of the authentication after the completion of the line connection. FIG. 10 is the timing chart showing a case where the function of the monitor  110  is suspended for the same term.  
         [0054]    In the case shown in FIG. 9, the re-set function (indicated by ({circle over (1)}) in FIG. 9) is suspended after the connection ({circle over (1)}) of the communication line (indicated by (b) in FIG. 9) until the log-on ({circle over (2)}) to the network (indicated by (c) in FIG. 9). On the other hand, in the case shown in FIG. 10, the function of the monitor (line quality monitor) indicated by (a) in FIG. 10 is suspended after the connection ({circle over (3)}) of the communication line (indicated by (b) in FIG. 10) until the log-on ({circle over (4)}) to the network (indicated by (c) in FIG. 10).  
         [0055]    [0055]FIG. 11 is a flow chart for explaining the operation according to the second embodiment of the present invention. In FIG. 11, the operations of the modems  11  and  21  and those of the applications are separately shown. It should be noted that FIG. 11 corresponds to FIG. 6, and in FIG. 11, those steps that are the same as those corresponding steps in FIG. 6 are designated by the same reference numerals.  
         [0056]    As shown in FIG. 11, when the connection of the communication line is completed in step S 41 , in step S 111 , the function of either the monitor  110  or the re-setting part  120  is suspended. Thereafter, in step S 42 , the data transmission/reception is started between the user terminal  10  and the server  20  of the ISP via the communication line  30 .  
         [0057]    Hence, the application of the server  20  starts the authentication operation and requests the ID/password from the user terminal  10  in step S 61 . In response to the request, the user terminal  10  transmits the ID/password in step S 62 . The server  20  confirms the transmitted ID/password in step S 63 , and whether or not the authentication succeeds is determined in step S 64 . When the authentication succeeds (YES in step S 64 ), the user terminal  10  is connected to the network in step S 65 . Accordingly, in step S 112 , the function of either the monitor  110  or the re-setting part  120  which function is suspended in step S 111  is reactivated.  
         [0058]    On the other hand, in the modem  11 , while the communication line  30  is connected (step S 43 ), even in a case where the degradation of the communication state occurs due to noise or the like in step S 44 , since the function of either the monitor  110  or the re-setting part  120  is suspended in step S 111 , the decision result in step S 45  or S 46  is NO. Thus, the process returns to step S 43 , and the process of steps S 43  through S 46  is repeated. It should be noted that whether or not the monitor  110  is activated (monitor function is ON) is determined in step S 45 . Additionally, in step S 46 , whether or not the re-setting part  120  is activated (re-setting function is ON) is determined.  
         [0059]    After the function of either the monitor  110  or the re-setting part  120  is reactivated in step S 112 , both decision results in steps S 45  and S 46  are YES. Consequently, in step S 47 , the modem  11  suspends the normal data transmission/reception, and starts the re-set operation using the communication line  30  in step S 48 . Then, when the re-setting (, new setting or updating) of the communication parameters is completed by the re-set operation, the normal data transmission/reception that is suspended in step S 47  is restarted in step S 49 , and the communication line  30  assumes a connected state in step S 50 .  
         [0060]    Here, as mentioned above, since the normal data transmission/reception is suspended (since step S 47 ) during the re-set operation in step S 48 , the service for the user using the network is suspended. However, the authentication operation is already completed (YES in step S 64 ), and the communication line  30  used in the authentication operation remains being connected. Therefore, the authenticated information is maintained as is. As soon as the normal data transmission/reception is restarted in step S 49 , the user can enjoy the service via the network that is the desired object again.  
         [0061]    Next, a description will be given of a software program and a computer-readable recording medium storing the software program according to the third embodiment of the present invention, by referring to FIG. 12.  
         [0062]    [0062]FIG. 12 is a block diagram showing the structure of the user terminal  10 . In FIG. 12, the user terminal  10  includes a CPU  10   a,  a memory part  10   b,  a CD-ROM drive  10   c,  an input part  10   e,  a display  10   f,  a hard disk drive (HDD)  10   g  and the modem  11  that are connected via a bus  10   h.  The memory part  10   b  is made of RAM, ROM and the like. The input part  10   e  includes a keyboard and a mouse, for example. A CD-ROM  10   d  may be set to the CD-ROM drive  10   c.    
         [0063]    The software program according to the third embodiment of the present invention corresponds to the software program (driver software) described with reference to FIG. 7 and so forth, and causes a computer (in this case, the user terminal  10 ) to carry out the functions of the communication apparatus explained in the above embodiments. Here, the software program is stored in a portable recording medium such as the CD-ROM  10   d.  The CD-ROM  10   d  may be set to the CD-ROM drive  10   c.  The software program may be installed from the CD-ROM  10   d  to the hard disk drive  10   g,  transferred to the memory part  10   b,  and then read by the CPU  10   a.    
         [0064]    The recording medium such as the CD-ROM  10   d  corresponds to the computer-readable recording medium according to the third embodiment of the present invention, of course. However, the computer-readable recording medium according to the present invention is not limited to the portable recording medium such as the CD-ROM  10   d,  but also includes various kinds of media that are accessible by a computer. For example, IC card memories, flash memories, floppy disks, optical disks including DVDs, magneto-optical disks such as MOs, and the like. In addition, it should be noted that the software program according to the present invention may be provided not only by the portable recording media as mentioned above, but also by downloading from another computer system (not shown) by using the modem, for example.  
         [0065]    Further, in the above-described embodiments, the function of either the monitor  110  or the re-setting part  120  is suspended until the completion of the authentication operation after the connection of the communication line  30 . However, the present invention is not restricted to the embodiments. For example, as indicated by T in FIGS. 9 and 10, the function of either the monitor  110  or the re-setting part  120  may be automatically reactivated by the function of a timer after a predetermined time T. In this case, by setting the time for the timer to time out a little longer than the time required for the completion of the normal authentication operation, it is possible to avoid the authentication ending in failure because the reset operation is activated and the communication line  30  is disconnected by the time out before the completion of the authentication operation. However, when the time interval for the time out is set too long, the activation of the re-set operation delays. Consequently, another problem occurs in that the communication state remains unstable for a long time. Thus, the time interval for the time out should be set to a suitable length.  
         [0066]    As described above, according to the present invention, by suspending the function relating to the re-set operation of the communication parameters in the authentication operation, the authentication operation is normally completed. In addition, by the completion of the authentication, the user can enjoy the desired service via the network in a timely manner. Thus, it is possible to effectively improve the service for the user.  
         [0067]    The present invention is not limited to the specifically disclosed embodiments, and variations and modifications may be made without departing from the scope of the present invention.  
         [0068]    The present application is based on Japanese priority application No. 2002-089534 filed on Mar. 27, 2002, the entire contents of which are hereby incorporated by reference.