JP2007104524A - Ip gateway, communication method, program, and its recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an IP gateway capable of providing a stable communication even for a FAX communication through a wide area network. <P>SOLUTION: A means is provided for encoding a voice signal received by a FAX machine into an IP packet. Further, a packet transmitting speed storage means stores a FAX number specifying the FAX machine of a communication opposite party, an IP packet transmitting speed in a past communication with the FAX machine corresponding to the FAX number, and a time of the past communication by associating one another. When communicating, a speed setting means sets the IP packet transmitting speed in the communication with the FAX machine of the communication opposite party based on the FAX number of the communication opposite party, the time of the communication, and the packet transmitting speed storage means. A communication means provides the IP gateway for transmitting the IP packet at the IP packet transmitting speed set by the speed setting means. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an IP gateway, a communication method, a program, and a recording medium thereof, and more particularly, to an IP gateway, a communication method, a program, and a recording medium thereof that improve communication efficiency with a counterpart.

  In recent years, voice communication via an IP network, represented by a so-called IP telephone, has been used. Calls are made with a call partner from a narrow area network such as an in-house network via a wide area network such as the Internet. By using a wide area network that is generally open, communication costs can be kept low.

  Further, not only voice communication but also FAX communication is performed via the IP network. A plurality of different types of FAX communication have been proposed, but a typical example is a FAX communication method using voice packets. This is a mechanism in which a FAX tone signal or voice transmitted from a FAX terminal is converted into an IP packet by a VoIP (Voice over IP) gateway (hereinafter referred to as an IP gateway) and transmitted to the destination IP gateway. In this system, if voice communication is possible between IP gateways, the FAX apparatus connected to the IP gateway is cost-effective and technically advantageous in that a conventional apparatus can be used.

In the conventional FAX apparatus, when an error occurs in communication and a retransmission request is received from the partner FAX apparatus, there is a technique of performing communication at a communication speed equal to or lower than the communication speed at the time of the error occurrence.
JP 2001-268158 A

  In conventional fax communication using a telephone line, the available bandwidth and line status are stable, so there is no need to consider the line status, and the communication speed is set based on compatibility with the destination fax machine. Then, stable communication with the other party was established. However, in communication between FAX apparatuses intervening with a wide area network, the state of the wide area network is affected in addition to compatibility with the counterpart FAX apparatus. In other words, the signal that reaches the destination FAX machine is likely to be distorted due to various factors on the wide area network, and failures such as connection delay, connection failure, transmission waiting delay on the IP network, transfer delay, packet loss, etc. It is very likely to occur compared to the case of using a telephone line.

  The present invention has been proposed based on the above-described conventional circumstances, and an object thereof is to provide stable communication even in FAX communication via a wide area network.

  The present invention employs the following means in order to achieve the above object. That is, the IP gateway according to the present invention includes means for encoding a voice signal received from a FAX apparatus into an IP (Internet Protocol) packet. The packet transmission rate storage means includes a FAX number for identifying a FAX device as a communication partner, an IP packet transmission rate at the time of past communication with the FAX device corresponding to the FAX number, and a time at the time of the past communication. Are stored in association with each other, and during communication, the speed setting means communicates with the communication partner's FAX apparatus based on the communication partner's FAX number, the time of communication, and the packet transmission speed storage means. Set the IP packet transmission speed at the time. The communication means transmits the IP packet at the IP packet transmission speed set by the speed setting means.

  Also, a counting means for counting the number of retransmission requests from the other party at the time of communication, a re-speed setting means for setting a low packet transmission speed when the counted number of retransmission requests exceeds a predetermined value, and a re-speed setting If the packet transmission speed is set low by the means, the FAX number of the partner at the time of the communication, the IP packet transmission speed at the time of the communication, and the time at the time of the communication are added to the transmission speed storage means. There is a configuration including additional update means for updating.

  The determination means sets the IP packet transmission speed to the highest speed when the information related to the FAX number of the communication partner is not stored in the transmission speed storage means, and the communication means is set by the determination means. There is also a configuration in which the IP packet is transmitted at an IP packet transmission speed.

  Furthermore, there is a configuration provided with a deletion unit that monitors the expiration date of the record stored in the sending speed storage unit and deletes the record whose expiration date has expired.

  Here, the IP gateway can be embodied using a computer. In that case, each of the above means is embodied by operating a program on a computer. The program is a series of commands to the computer, and can be provided through an electric communication line such as the Internet by expressing the commands as an electrical signal. It can also be recorded on a computer-readable recording medium for distribution or sale.

  The IP gateway or the like according to the present invention can provide stable communication even in FAX communication via a wide area network.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention. In addition, the following embodiment is an example which actualized this invention, Comprising: It is not the thing of the character which limits the technical scope of this invention.
(Embodiment 1)
First, the configuration of an IP (Internet Protocol) gateway according to an embodiment of the present invention will be described.

  FIG. 1 is a schematic functional block diagram of an IP gateway 101 according to the present invention. The IP gateway 101 includes a voice communication interface 102, a communication destination determination unit 103, a communication destination storage unit 104, a speed setting unit 105, a packet transmission rate storage unit 106, an encoding unit 107, a communication unit 108, and a data communication interface 109. A decoding unit 110, a speed resetting unit 111, a counting unit 112, and a deleting unit 113. The voice communication interface 102 corresponds to the voice network interface 305 in FIG. 3 and is connected to a device that performs voice communication, that is, a FAX device 201, a telephone 202, and the like. The data communication interface 109 corresponds to the data network interface 306 in FIG. 3 and is connected to the Internet, which is a wide area network. Note that the IP gateway here refers to a device that converts a voice signal into an IP packet. In this embodiment, the IP gateway has a router function 203 and can also route an IP packet. When the router function 203 is not provided, a router that performs IP packet routing processing is interposed between the IP gateway 101 and the Internet 204. Details of other means will be described later.

  FIG. 2 shows a configuration example of a FAX communication system using an IP gateway, which is connected to a plurality of IP gateways 101, 205, etc., FAX apparatuses 201, 206, etc. via the Internet 204. In addition, a number of routers 207 are connected to the Internet 204, and are connected to a plurality of personal computers (PCs) 208 via a narrow area network 209 so as to be communicable.

  FIG. 3 is a schematic configuration diagram of an IP gateway, which includes a central processing unit (CPU) 301, a random access memory (RAM) 302, a read only memory (ROM) 303, an HDD 304, a voice network interface 305, and a data network. The interface 306 is connected via the internal bus 307. The CPU 301 operates as each unit shown in FIG. 1 by using, for example, the RAM 302 as a work area and executing a program stored in the ROM 303, the HDD 304, or the like. The voice network interface 305 is connected to a FAX apparatus or a telephone and can perform voice communication with the FAX apparatus or the telephone. The data network interface 306 is connected to the Internet 204, which is an IP network, and can exchange data with other devices.

  Next, processing in the IP gateway 101 will be described with reference to FIGS.

  First, a user who intends to transmit a FAX using the FAX apparatus 201 reads a document to be transmitted from the scanner of the FAX apparatus 201 and at the same time FAX of the FAX apparatus (for example, the FAX apparatus 206) as a transmission destination. Enter the number. The FAX number is a unique number that can identify the FAX apparatus 206 that is a communication partner. Note that the FAX apparatus here is a generally popular FAX apparatus corresponding to a general telephone line (switched line).

  When the FAX number is input and the document to be transmitted is read, the FAX apparatus 201 enters an off-hook state, and when the off-hook state is detected by the voice communication interface 102 of the IP gateway 101, the IP gateway 101 and the FAX apparatus 201 Is in a communicable state (FIG. 5: S501).

  When communication is enabled, the FAX transmitting apparatus 201 transmits a tone signal to the IP gateway 102 based on the input FAX number (FIG. 5: S502).

The tone signal is received by the communication destination determining means 103 via the voice communication interface 102 and converted into a numerical value. Further, the communication destination determination unit 103 refers to the communication destination storage unit 104 based on the converted numerical value, and acquires the IP address of the corresponding destination FAX terminal (FIG. 5: S503).
That is, the communication destination storage means 104 stores a FAX number-IP address table 401 shown in FIG. 4A. In this table, a destination number 402 that is the number of the destination FAX apparatus and a destination FAX are stored. The IP address 403 of the device is stored in association with it. By referring to the partner number 402 based on the converted numerical value, the corresponding partner IP address 403 can be acquired. In the present embodiment, the FAX number-IP address table 401 is stored in the communication destination storage unit 104. For example, when the IP gateway 101 communicates with a terminal provided on the Internet 204, The destination IP address 403 may be acquired.

  When the IP address (partner IP address) of the destination FAX apparatus 206 is acquired, the communication destination determination unit 103 transmits the destination IP address 403 and the destination number 402 to the speed setting unit 105.

  When the destination IP address 403 and destination number 402 are acquired, the speed setting means 105 refers to the packet sending speed storage means 106 and sets the packet sending speed when communicating with the FAX apparatus 206 (FIG. 5: S504). The packet transmission speed can be defined as an interval at which packets are transmitted to the data network, and the above setting is performed as follows.

  First, the speed setting means 105 refers to the packet transmission speed table 411 shown in FIG. 4B. In the packet rate table 411, the destination number 412 which is the FAX number of the destination, the packet transmission rate 413 which has obtained a good result in the past communication, and the communication time 414 showing the communication time as a range. And the due date 415 of the record are stored in association with each other. The speed setting means 105 can search for a matching record from the destination number 412 using the packet sending speed table 411, the received destination number, and the current time. The current time is not limited to hours, minutes, and seconds, but the range to which the current time belongs is used. In this embodiment, it is assumed that one day (24 hours) is divided into eight groups every three hours, with 0:00 being the start time. In other words, assuming that the current time is 14:20, the current time is searched as belonging to the group “12:00 to 15:00”. The search is made based on the destination number, but the same applies to the case where the search is made based on the destination IP address. In this case, the destination IP address is stored in the destination number 412 of the packet transmission rate table 411.

  Here, when a record corresponding to the search is found, a value corresponding to the packet transmission rate 413 of the record is set as a packet transmission rate during communication (FIG. 5: S504 Yes → S505).

  If no record corresponding to the above search is found, the packet transmission speed is set to the highest value (here, 1 msec interval) (FIG. 5: S504 No → S506).

  When the packet transmission speed is set as described above, the setting content is notified to the communication means 108, and the packet transmission to the terminal corresponding to the destination IP address is transmitted at intervals determined by the setting content. (FIG. 5: S507).

  When the packet transmission speed is set, the communication unit 108 transmits a packet for establishing a circuit to the destination IP address 403, whereby the IP gateway to which the FAX device 206 corresponding to the IP address is connected. In 205, a packet for establishing the circuit is received. When the packet is received, a signal for establishing a line is transmitted to the FAX apparatus 206 corresponding to the IP address, and the line is established based on the signal.

  As described above, a line via the Internet 204 is established between the FAX apparatuses 201 and 206.

  Next, when the line is established, the FAX apparatus 201 is notified to that effect, and the FAX apparatus 201 that receives the notification transmits the document data read from the scanner to the IP gateway 101 as an audio signal.

  The voice signal of the document is received by the encoding means 107 via the voice communication interface 102, packetized by encoding, and received by the IP gateway 205 via the Internet 204. The IP gateway 205 decodes the received packet and returns it to a voice signal, and then transmits it to the FAX apparatus 206. As a result, even if the FAX uses a normal audio signal, it can be transmitted through the Internet 204 in the conventional procedure.

  As described above, since the speed setting unit 105 transmits a packet based on the communication time and the packet transmission speed at which a good result was obtained during the past communication, the retransmission request from the FAX apparatus 206 is There is almost no fax communication. In particular, traffic on the Internet 204 varies greatly depending on the time of use. In other words, since most of the use of the Internet is concentrated from evening to midnight, FAX communication in this time zone tends to be unstable. On the other hand, there is little Internet traffic from midnight to morning, and even if the speed of FAX communication is increased, it is difficult to become unstable. However, depending on the performance of the other party's IP gateway, if the speed is increased too much, for example, packets cannot be stored in the buffer, resulting in packet loss and an increase in retransmission request transmission. Therefore, in this application, the stability of FAX communication is ensured by changing the packet transmission speed according to the destination and time.

  The above-mentioned “packet transmission speed at which a good result was obtained during past communication” is stored in the packet transmission speed table 411. This storage is performed as follows. That is, first, as described above, the packet transmission speed is set to the highest speed in the case of communication with a partner with no communication performance in the past.

  In such a state, when there is a lot of traffic in the Internet 204, the signal reaching the destination FAX apparatus is likely to be distorted, connection delay, connection failure, transmission waiting delay on the IP network, transfer delay, packet Loss and other obstacles are likely to occur. In such a case, a retransmission request for recovery of a predetermined (error) audio signal is issued from the partner FAX apparatus. The retransmission request is counted by the count unit 112 via the IP gateway 205 and the data communication interface 109 of the IP gateway 101 and the communication unit 108. The speed resetting unit 111 constantly compares the number of retransmission requests counted by the counting unit 112 with a predetermined threshold value. If the threshold value is exceeded, it is determined that an error is likely to occur at the current packet transmission rate, and the communication unit 108 is notified that the packet transmission rate is set to a slow value (resetting). Then, the communication unit 108 continues communication with the IP gateway 205 with the reset value.

  At the same time, the speed resetting means 111 resets the count value and adds / updates the destination number 412, the reset packet sending speed 413, the transmission time 414, and the record time limit 4 15 to the packet transmission speed storage means 106. To do. By repeating this process, the “packet sending speed at which a good result is obtained” is finally stored in the packet sending speed storage means 106.

  Note that the record time limit 415 is an expiration date of the record, and for example, a date after a predetermined date (for example, one month) from the date when the record is added / updated is set at the time of addition / update. The deleting unit 113 refers to the record time limit 415 and deletes the record whose time limit has expired, so that a new packet transmission speed can be set according to the change in the configuration of the Internet, the destination IP gateway, and the destination FAX apparatus 206. Can be set.

  The IP gateway or the like according to the present invention changes the packet transmission speed based on the communication time and the packet transmission speed at which a good result was obtained in the past communication, and thus supports FAX communication in a network where the communication is not stable. It is useful as an IP gateway or the like.

1 is a schematic functional block diagram of an IP gateway according to the present invention. The figure which shows the structural example of the FAX communication system using an IP gateway. 1 is a schematic configuration diagram of an IP gateway. The figure which shows an example of a FAX number-IP address table and a packet transmission speed table. The flowchart which shows the process which determines the packet transmission rate of an IP gateway.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 IP gateway 102 Voice communication interface 103 Communication destination determination means 104 Communication destination storage means 105 Speed setting means 106 Packet transmission speed storage means 107 Encoding means 108 Communication means 109 Data communication interface 110 Decoding means 111 Speed resetting means 112 Count means 113 Delete means 301 CPU
302 RAM
303 ROM
304 HDD
305 Voice network interface 306 Data network interface 307 Internal bus

Claims (7)

Means for encoding an audio signal into an IP (Internet Protocol) packet;
Packet transmission that associates and stores a FAX number that identifies a FAX apparatus as a communication partner, an IP packet transmission speed at the time of past communication with the FAX apparatus corresponding to the FAX number, and a time at the time of the past communication Speed storage means;
Speed setting means for setting an IP packet transmission speed at the time of communication with the communication counterpart FAX apparatus based on the FAX number of the communication counterpart, the time at the time of communication, and the packet transmission speed storage means;
Communication means for sending the IP packet at the IP packet sending speed set by the speed setting means;
IP gateway with Furthermore, a counting means for counting the number of retransmission requests from the other party during communication,
If the counted number of retransmission requests exceeds a predetermined value, a re-speed setting means for setting a low packet transmission speed;
When the packet transmission rate is set low by the re-speed setting means, the transmission rate storage is performed by associating the partner's fFAX number during the communication, the IP packet transmission rate during the communication, and the time during the communication. Additional update means to add / update to the means;
The IP gateway according to claim 1, further comprising: The determination means sets the IP packet transmission speed to the highest speed when information related to the FAX number of the communication partner is not stored in the transmission speed storage means,
The IP gateway according to claim 1, wherein the communication unit transmits the IP packet at an IP packet transmission rate set by the determination unit.   Further, a deletion means for monitoring a use time limit of a record associated with the FAX number, the IP packet sending speed, and the time at the time of communication stored in the sending speed storage means, and deleting the record whose use time limit has ended. The IP gateway according to claim 1, comprising: Packet transmission speed storage means for storing a FAX number for identifying a FAX apparatus as a communication partner, an IP packet transmission speed at the past communication with the FAX apparatus corresponding to the FAX number, and a time at the past communication in association with each other. A step of setting an IP packet transmission speed at the time of communication with the communication partner FAX apparatus based on the communication partner FAX number and the communication time;
A communication step of transmitting the IP packet at a set IP packet transmission rate;
An IP gateway communication method comprising: On the computer,
Packet transmission speed storage means for storing a FAX number for identifying a FAX apparatus as a communication partner, an IP packet transmission speed at the past communication with the FAX apparatus corresponding to the FAX number, and a time at the past communication in association with each other. A step of setting an IP packet transmission speed at the time of communication with the communication partner FAX apparatus based on the communication partner FAX number and the communication time;
A communication step of transmitting the IP packet at a set IP packet transmission rate;
A program that executes On the computer,
Packet transmission rate storage means for storing a FAX number for identifying a FAX apparatus as a communication partner, an IP packet transmission speed at the past communication with the FAX apparatus corresponding to the FAX number, and a time at the past communication. Setting the IP packet transmission speed during communication with the communication partner FAX device based on the communication partner FAX number and the communication time;
A communication step of transmitting the IP packet at a set IP packet transmission rate;
The computer-readable recording medium which recorded the program which performs this.

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