Data communication unit

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a data communication device having a data communication function for realizing mobile computing on a personal digital assistant (PDA) or a laptop computer.

【0002】

[Conventional technology]

In mobile computing with PDAs and laptops that have e-mail sending / receiving functions and web (Web) browser functions, for example, small cards (data communication devices) equipped with PHS data communication functions can be used in PC card slots. It is designed to be installed in a CompactFlash® slot to connect to a communication network.

【0003】

For example, by dialing up (making a call) from a laptop computer to an ISP (Internet service provider) on the Internet via the above data communication device, it is possible to obtain e-mail and web information via the Internet. The web browser function allows you to access a specified URL (uniform, resource, locator) on the Internet and display the home page.

【0004】

In addition, by starting a predetermined application software and dialing up to a predetermined access point (telephone number), it becomes possible to connect to a specific local area network (LAN) and send / receive IP packets.

【0005】

The data communication device is realized as a PC card based on the PCMCIA (Personal Computer Memory Card International Association) standard and a compact flash (Compact Flash (registered trademark of SanDisk Corporation)) advocated by CFA (Compact Flash Association).

【0006】

The data communication device is inserted into a laptop computer or the like to dial up in response to a connection request from the personal computer, and terminates the dial-up connection in response to a disconnection request from the personal computer or the connection destination.

【0007】

Such a data communication device is used as a means for connecting to a network by wireless communication from an ISDN (Integrated Services Digital Network), an analog line, or a place where a wired communication infrastructure such as a LAN network is not maintained, that is, outdoors or in a car. It is useful.

【0008】

[Problems to be Solved by the Invention]

By the way, when the homepage of a predetermined site on the Internet is displayed on a web browser, the dial-up connection may take a long time without data transmission / reception on the line. However, in the dial-up connection, the connection time is charged, so that there is a problem that unnecessary charging occurs in the above connection state.

【0009】

Further, during the dial-up connection, there is also a problem that the power consumption of the data communication device becomes larger than that in the dial-up disconnected state. For example, if a compact flash type PHS is inserted into a compact flash slot (TYPE II) and used, its power consumption is about 3 mW in standby mode, but it becomes about 380 mW during dial-up connection. For this reason, when using a laptop computer or PDA that is battery-powered outdoors or in a car, the operating time of the laptop computer or PDA becomes shorter because the power consumption during dial-up connection of the data communication device is large. There is also the problem of closing.

【0010】

To prevent the above problems with current technology, disconnect the dial-up connection when it seems that data communication will not be performed for a long time, and manually send a connection request again when communication is resumed. There is a need. It is extremely complicated and time-consuming to manually repeat dial-up connection and disconnection during data transmission / reception, which is not realistic.

【0011】

An object of the present invention is to provide a data communication device that prevents the occurrence of unnecessary charges and also suppresses power consumption.

【0012】

[Means for solving problems]

The above purpose is to connect to an interface unit that sends and receives IP packets to and from an information processing device, and to connect to a telephone line when a communication request with an external network is received to perform relay processing of the IP packet transfer. An IP processing unit that disconnects the telephone line when the communication time exceeds a predetermined set time, a communication unit that transmits / receives the IP packet between the external network under the control of the IP processing unit, and the external network. On the other hand, it is achieved by a data communication device characterized by having a dial-up unit for dial-up connection.

【0013】

In the data communication device of the present invention, the IP processing unit determines whether or not the transfer destination of the IP packet is the external network.

【0014】

BEST MODE FOR CARRYING OUT THE INVENTION

A data communication device according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. First, a schematic configuration of the data communication device according to the present embodiment will be described with reference to FIG. The data communication device 1 shown in FIG. 1 has a dial-up function and a communication function for a public network, and an IP processing unit 2 that interprets an IP packet and determines whether a dial-up connection is necessary. The IP processing unit 2 is composed of at least a control unit 4, ROM 6 and RAM 8.

【0015】

Conventional wireless communication apparatus, the information processing apparatus side child, such as a personal computer and a PDA is recognized as Myunikeshon device (COM devices), not a function of the IP packet processing, such as a router. On the other hand, the data communication device 1 according to the present embodiment is configured to be recognized as a network adapter from the personal computer side, and the IP processing unit 2 can perform transmission / reception processing of IP packets.

【0016】

The IP processing unit 2 interprets the IP packet sent from the PC, determines whether to dial up according to the preset settings, and dials the PHS communication unit 12 when making a dial-up connection. Instruct the connection. In addition, when the IP packet is monitored and the non-communication time exceeds the set time, the dial connection disconnection instruction is output to the PHS communication unit 12.

【0017】

In ROM 6 or RAM 8 of the IP processing unit 2, in addition to the software for operating the above functions, conditions for determining whether to perform dial-up and settings for no communication time until automatic disconnection are stored. ..

【0018】

The control unit 4 of the IP processing unit 2 is connected to an interface unit 10 that exchanges signals with a personal computer or the like. The interface unit 10 has a connector shape that matches the physical shape of the connection destination. For example, it has a PC card, CompactFlash, or USB (Universal Serial Bus) connector. The interface unit 10 converts a physical interface with a personal computer (PC card I / F, USB I / F, etc.) into an electric signal that can be processed by the CPU.

【0019】

Further, the data communication device 1 has a PHS communication unit 12. The PHS communication unit 12 is a communication unit 21-1 that sends and receives IP packets to and from an external network under the control of the IP processing unit 2, and a dial-up unit 12-2 that makes a dial-up connection / disconnection to the external network. And have. Communication-related commands and IP data are sent from the control unit 4 of the IP processing unit 2 to the communication unit 21-1. The dial-up unit 12-2 has a dial-up communication function to the PHS line, and dial-up connection or disconnection is performed according to the instruction of the IP processing unit 2. The PHS communication unit 12 sends out an IP packet by wireless communication via the antenna 14.

【0020】

Next, the operation procedure of the data communication device according to the present embodiment will be described with reference to the flowchart shown in FIG. As a premise, it is assumed that the data communication device 1 is installed in the card slot of an information processing device such as a personal computer or a PDA or is connected by USB.

【0021】

First, when an IP packet is issued from an information processing device (not shown) (step S1), the interface unit 10 converts the IP packet into an electric signal that can be processed by the control unit 4 of the IP processing unit 2. As a result, the IP packet is received by the control unit 4 in the IP processing unit 2 via the interface unit 10 (step S2).

【0022】

Based on the IP header information of the received IP packet, the control unit 4 of the IP processing unit 2 determines whether or not it is necessary to connect to the Internet by dial-up according to the preset settings (step S3). ), If dial-up is required, instruct dial-up unit 12-2 of PHS communication unit 12 to dial-up. Based on the instruction, the PHS communication unit 12 dials up to a predetermined ISP (step S4).

【0023】

Here, to briefly explain the conditions for determining whether or not to perform dial-up, first, a dial-up connection is performed at the time of requesting a specific service such as a query to a DNS server. Second, a dial-up connection is made when a specific IP address for connecting to an external LAN network is received.

【0024】

In step S3, if the received IP packet is transferred to another LAN port to which the information processing device is connected, for example, it is determined that dial-up is not necessary, and the IP packet is discarded and dial-up is performed. End the series of processes without doing so (step S11).

【0025】

In step S4, when the line is connected by dialing up to the ISP, it is connected to the specified server of the ISP after being authenticated by the ID and password such as the authentication number (step S5). Next, IP packets are sent and received between the data communication device 1 and the ISP server (step S7).

【0026】

The IP processing unit 2 monitors whether or not IP packets are transmitted and received (step S8), and determines whether or not there is no transmission / reception for more than the set time of no communication (step S9). If the set time elapses in the non-communication state, the control unit 4 sends a command to the PHS communication unit 12 to disconnect the dial-up connection with the ISP server. In response to this, the dial-up unit 12-2 of the PHS communication unit 12 disconnects the dial-up connection with the ISP, and a series of processes is completed (step S10).

【0027】

Next, the difference in communication charges between the data communication device 1 and the conventional data communication device according to the present embodiment will be described. Here, the communication charge is calculated when the homepage of a certain site on the Internet is downloaded for 15 seconds and the act of reading the homepage for 5 minutes is repeated 5 times. It takes 5 seconds to establish the communication procedure between the data communication device and IPS on the Internet, and the communication fee is 10 yen / minute. The data communication device 1 is set to automatically disconnect when a non-communication state continues for 2 minutes. Under the above conditions, with the conventional data communication device, the total communication time is 21 minutes 20 seconds = 220 yen, whereas with this data communication device 1, the total communication time is 11 minutes 40 seconds = 120 yen. Communication charges can be saved to about 40 to 50% of the conventional one.

【0028】

As described above, according to the present embodiment, even if the dial-up connection may take a long time without data transmission / reception, the dial-up connection is automatically canceled and the line is disconnected when the predetermined set time is reached. Since it can be disconnected, there is no need to worry about unnecessary charges as in the past.

【0029】

Further, even when the data communication device 1 requires a larger power consumption than the dial-up disconnection state during the dial-up connection, the unnecessary line connection state can be eliminated as much as possible, so that the data communication device 1 can be battery-powered outdoors or in the vehicle. It will be possible to minimize the effect on the operating time of laptop computers and PDAs that operate on.

【0030】

According to this embodiment, it is not necessary to temporarily disconnect the dial-up connection at a time when the data communication is not expected to be performed for a long time, or to manually send a connection request again when the communication is resumed. Therefore, the user can be freed from the troublesome work of manually repeating dial-up connection and disconnection frequently during data transmission / reception.

【0031】

The present invention is not limited to the above embodiment and can be modified in various ways. For example, in the above embodiment, PHS has been described as an example, but the present invention is not limited to this, and of course, it can be applied to a data communication device used in other mobile communication methods.

【0032】

[Effect of the invention]

As described above, according to the present invention, it is possible to realize a data communication device that prevents unnecessary billing and also suppresses power consumption.

[Simple explanation of drawings]

[Figure 1]

It is a figure which shows the schematic structure of the data communication apparatus by one Embodiment of this invention.

[Figure 2]

It is a flowchart which shows the operation procedure of the data communication apparatus by one Embodiment of this invention.

[Explanation of symbols]

1 Data communication device 2 IP processing unit 4 Control unit 6 ROM 8 RAM 10 Interface section 12 PHS communication unit 12-1 Communication Department 12-2 Dial-up section 14 antenna