JPH09200249A - Gateway device - Google Patents

Abstract

(57) Abstract: A gateway device having a simple configuration enables efficient data transfer. SOLUTION: A packet data identification means 12 for identifying a data type and a data size of packet data to be received from a LAN 102 side and transmitted to a public communication network 101 side.
6, a data amount calculation means 127 for calculating a data amount for each data type based on the data type and data size of the identified packet data, and the public communication network 101 according to the calculated data amount. A channel rate assigning means 128 for assigning an optimum transmission channel rate to the side is provided, and according to the data amount of each packet type of packet data received from the LAN 102 side and the remaining amount of data in the buffer for each data type An optimum transmission channel rate is assigned to the public communication network 101 side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gateway device, and more particularly to a public communication network and a LAN via a communication line.
And a gateway device which is connected to the public communication network side and performs the communication protocol conversion between the LAN side.

[0002]

2. Description of the Related Art In recent years, terminals connected to public communication networks and L
A device called a gateway device has been developed as a device for interconnecting terminals connected to an AN. This type of gateway device is connected to a public communication network and a LAN via a communication line and converts a communication protocol between the public communication network side and the LAN side.

For example, the public communication network is ISDN and the LAN is TCP (Transmission Conion).
control Protocol) / IP (Interne
When the protocol (tProtocol) is used, protocol conversion between the ISDN and the TCP / IP is performed.

In particular, the terminal connected to the public communication network is a telematic terminal, and ITU-T Recommendation T.264 is adopted as an ISDN protocol on the public communication network side. 90 is used, the data transferred in the LAN is packetized, and T.90 is used. 90 packets (for example, ITU-T Recommendation X.2)
5PLP, ISO / IEC8208, etc.) and LAN packets are mapped to perform protocol conversion.

However, the terminal connected to the public communication network is a multimedia terminal that handles various media such as audio data, video data and various data, and ITU- is used as an ISDN protocol on the public communication network side.
Recommendation H.T. When the H.320 is used, the data of each medium transferred in the LAN is logically multiplexed with a packet, and ITU-T Recommendation H.320 is added. It is necessary to perform mapping between the data of each medium multiplexed in 221 and the packet data of each medium logically multiplexed in the LAN.

In general, since the public communication network and the LAN have different transfer rates, in order to prevent overflow or underflow of the buffer for transmitting the data received from the LAN side to the public communication network side. , So that the transmission is performed at the transfer rate of the public communication network.
The terminal connected to N is controlled, and the gateway device controls the flow of data transferred from the LAN side.

As described above, the conventional gateway device is configured to control the LAN transfer rate in accordance with the transfer rate of the public communication network.

[0008]

However, when the data received from the LAN side is transmitted to the public communication network side, the conventional gateway device dynamically changes the transfer rate of each medium on the public communication network side. Since it is not configured to switch, there is a drawback that it is not possible to perform efficient transfer corresponding to changes in the amount of transmission data for each medium.

Further, in the terminal connected to the LAN, when communicating with the terminal connected to the public communication network, it is necessary to perform transmission control according to the transfer rate of the public communication network.

In this case, in the LAN, since only the data transfer substantially in accordance with the transfer rate of the public communication network can be performed, the transfer rate of the LAN cannot be maximized and the communication in the LAN is not possible. It had the drawback of being less efficient than

Further, when multipoint communication is realized by using the conventional gateway device, it is necessary to perform complicated flow control using a plurality of buffers corresponding to the number of points in the gateway device, resulting in cost increase. There was a drawback that led to.

In view of the above problems, it is an object of the present invention to enable efficient data transfer with a gateway device having a simple structure.

[0013]

A gateway device of the present invention is connected to a public communication network and a LAN via a communication line, respectively, and performs communication protocol conversion between the public communication network side and the LAN side. In the gateway device,
Packet data identification means for identifying the data type and data size of the packet data received from the LAN side and to be transmitted to the public communication network side, and the data type and data size of the packet data identified by the packet data identification means Based on the data amount calculation means for calculating the data amount for each data type, and the optimum transmission channel rate for the public communication network side in accordance with the data amount for each data type calculated by the data amount calculation means. And a channel rate allocating means for allocating.

Another feature of the present invention is that:
A gateway device connected to a public communication network and a LAN via a communication line for converting a communication protocol between the public communication network side and the LAN side.
Storage means for storing packet data received from the AN side and transmitted to the public communication network side in a buffer designated for each data type, and data in the buffer for each data type in which the packet data is stored by the storage means A data remaining amount detecting means for detecting a remaining amount, and a channel rate allocating means for allocating an optimum transmission channel rate to the public communication network side in accordance with the remaining data amount detected by the remaining data amount detecting means. Is characterized by.

Another feature of the present invention is that it further comprises switching instruction means for externally instructing switching of the transmission channel rate to the public communication network side, and the channel rate allocation means is the above-mentioned. An optimum transmission channel rate is assigned to the public communication network side in accordance with an external switching instruction issued via the switching instruction means.

Another feature of the present invention is that it further comprises timer means for notifying a certain fixed time interval, and the channel rate allocating means follows the timer notification made by the timer means. An optimum transmission channel rate is assigned to the public communication network side.

[0017]

Since the present invention comprises the above technical means, the data type and data size of the packet data to be received from the LAN side connected through the communication line and to be transmitted to the public communication network side are identified, and the identification is performed. Based on the data type and the data size of the packet data, the data amount for each data type is calculated, and the optimum transmission channel rate for the public communication network side is allocated according to the calculated data amount. .

According to another feature of the present invention, packet data received from the LAN side connected via a communication line and to be transmitted to the public communication network side is stored in a buffer designated for each data type. While being stored, the remaining amount of data in the buffer for each data type is detected, and the optimum transmission channel rate for the public communication network side is assigned according to the detected remaining amount of data.

According to another feature of the present invention, the transmission channel rate is switched to the public communication network side according to a switching instruction from the outside, so that the optimum transmission channel rate to the public communication network side is obtained. Will be assigned.

Further, according to another feature of the present invention, an optimum transmission channel rate is assigned to the public communication network side according to a timer notification of a certain time interval performed by the timer means.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION

[First Embodiment] A first embodiment of the gateway device of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a configuration diagram of an entire communication system including a gateway device according to a first embodiment of the present invention.

In FIG. 1, 101 is an ISDN, 102
Is a LAN, and 111 is an ISDN terminal connected to the ISDN 101. A gateway device 121 is connected to the ISDN 101 and the LAN 102 and performs communication protocol conversion between the ISDN and the LAN. 13
1 to 133 are LAN terminals connected to the LAN 102.

The gateway device 121 includes the line controller 1
22, LAN control section 123, system control section 124, memory 125, packet data identification means 126, data amount calculation means 127, and channel rate allocation means 128.

The line controller 122 uses the ISDN 101
It is for controlling the communication protocol of. LAN
The control unit 123 is for controlling the communication protocol of the LAN 102.

The system control unit 124 is for controlling the overall operation of the gateway device 121, and the memory 125 is for storing various information. The packet data identification means 126 is for identifying the data type and data size of the packet data received from the LAN 102 and to be transmitted to the ISDN 101.

The data amount calculating means 127 is for calculating the data amount for each data type, and the channel rate allocating means 128 is for allocating the optimum transmission channel rate to the ISDN 101.

In the gateway device 121 of the present embodiment having the above configuration, the gateway device 121 receives from the LAN 102,
When monitoring the packet data to be transmitted to the ISDN 101, the flowchart of FIG. 2 is applied.

As shown in FIG. 2, first, step S2
At 01, it is determined whether the packet data to be transmitted to the ISDN 101 is received from the LAN 102 by the LAN control unit 123. If it is determined that the packet data has been received, the process proceeds to step S202, and the packet data identification means 126 identifies the data type and data size of the received packet data.

Next, in step S203, it is determined whether or not the data type of the received packet data is voice data. As a result of the judgment, if the data type of the received packet data is voice data, the process proceeds from step S203 to step S205, and the data amount calculation means 127 determines the data size of the received packet data as the data amount of the voice data. Is stored in the memory 125.

On the other hand, if the result of determination in step S203 is that the data type of the received packet data is not voice data, the process proceeds from step S203 to step S204, and whether the data type of the received packet data is video data. Determine whether or not. As a result of this determination, when the data type of the received packet data is video data, the process proceeds from step S204 to step S206, and the data amount calculation means 127 sets the data size of the received packet data to the data amount of the video data. Is stored in the memory 125.

Further, as a result of the determination in step S204, if the data type of the received packet data is not video data, that is, if the data type of the received packet data is LSD (Low Speed Data) data, Then, the process proceeds from step S204 to step S207, and the data amount calculation means 127 adds the data size of the received packet data to the cumulative value of the data amount of the LSD data and stores it in the memory 125.

When the optimum transmission channel rate for the ISDN 101 is assigned in the gateway apparatus 121 of the present embodiment thus configured, the flowchart of FIG. 3 is applied. That is, first, in step S301, the channel rate allocating means 128 selects the optimum transmission channel rate for the ISDN 101 according to the cumulative value of each data amount of audio / video / LSD stored in the memory 125.

Next, in step S302, the line control unit 122 determines the ITU-T recommendation H.264 according to the selected transmission channel rate. A BAS (bit rate allocation signal) command 221 is transmitted to the ISDN terminal 111.

(Second Embodiment) A second embodiment of the present invention will be described in detail below with reference to the drawings. FIG.
FIG. 4 is a configuration diagram of an entire communication system including a gateway device according to a second exemplary embodiment of the present invention.

In FIG. 4, 401 is ISDN, 402
Is a LAN, 411 is an ISDN terminal connected to the ISDN 401, and 421 is the ISDN 401 and the L.
The gateway device is connected to the AN 402 and performs communication protocol conversion between ISDN and LAN. 431-43
A LAN terminal 3 is connected to the LAN 402.

The gateway device 421 is the ISDN 40.
Line control unit 42 for controlling the communication protocol No. 1
2, L for controlling the communication protocol of LAN 402
The AN control unit 423, the system control unit 424 for controlling the overall operation of the gateway device 421, the memory 425 for storing various information, the packet data received from the LAN 402 and to be transmitted to the ISDN 401 are designated for each data type. Packet data storage means 426 for storing the data in the buffer, and data remaining amount detection means 4 for detecting the data remaining amount in the buffer for each data type.
27, and a channel rate assigning means 428 for assigning an optimum transmission channel rate to the ISDN 401.

When the gateway device 421 of the present embodiment configured as described above stores the packet data received from the LAN 402 and to be transmitted to the ISDN 401, the flowchart shown in FIG. 5 is applied.

As shown in FIG. 5, first, in step S5
01, the LAN control unit 423 causes the ISDN 40
It is determined whether the packet data to be transmitted to 1 is received from the LAN 402. If the result of this determination is that it has been received, processing advances to step S502, and the packet data storage means 426 identifies the data type of the received packet data.

Next, in step S503, it is determined whether the identified data type of the packet data is voice data. As a result of the determination, if the data type of the received packet data is voice data, step S
In step S505, the packet data storage unit 426 stores the received packet data in the audio buffer assigned to the memory 425.

If the result of determination in step S503 is that the data type of the received packet data is not voice data, the flow advances from step S503 to step S504 to see if the data type of the received packet data is video data. Determine whether or not. As a result of this determination, when the data type of the received packet data is video data, the process proceeds from step S504 to step S506, and the packet data storage unit 426 causes the memory 42 to operate.
The received packet data is stored in the video buffer allocated to No. 5.

As a result of the determination in step S504, if the data type of the received packet data is not video data, the data type of the received packet data is LSD (Low Speed Data) data.
The process proceeds from step 504 to step S507, and the L assigned to the memory 425 by the packet data storage unit 426.
The received packet data is stored in the SD buffer.

In the gateway device 421 of this embodiment, the flow chart of FIG. 6 is applied when allocating the optimum transmission channel rate to the ISDN 401. First, in step S601, the remaining data amount detecting means 427 detects the remaining amount of data in each buffer for audio / video / LSD assigned to the memory 425.

Next, in step S602, the audio / video / L detected by the remaining data amount detecting means 427 is detected.
Depending on the remaining amount of data in each SD buffer, IS
The optimum transmission channel rate for the DN 401 is selected by the channel rate allocating means 428.

Next, in step S603, the line control unit 422 makes the ITU-T recommendation H.264 according to the selected transmission channel rate. The BAS (bit rate allocation signal) command 221 is transmitted to the ISDN terminal 411.

(Other Embodiments) In the above embodiment, ISDN is used as the protocol on the public communication network side.
H. Although an example in which the 320 protocol is adopted has been described, in addition to this, for example, PSTN (Public Switched Te
lephone Network). The same applies to the 324 protocol.

The type and protocol of the public communication network are not particularly limited as long as the channel rate for each data type can be dynamically assigned at a fixed rate.

As a matter of course, as the LAN side protocol, various protocols can be applied as long as they are protocols for packetizing and transferring data. The communication between the terminal connected to the public communication network and the terminal connected to the LAN may be one-to-one communication or multipoint communication.

Further, the timing for initializing the cumulative value of the data amount for each data type in the first embodiment may be initialized every time the optimum transmission channel rate is selected, except when communication is started. The initialization may not be performed.

As the timing for activating the procedure for allocating the optimum transmission channel rate to the public communication network side, for example, the operator of the gateway device or another terminal instructs switching of the transmission channel rate to the public communication network side. It is also possible to provide an instruction means for this and activate it according to a switching instruction from the outside.

Alternatively, for example, timer means for notifying a certain time interval may be provided inside the gateway device, and the gateway device may be activated according to the timer notification inside.

Further, as a method of allocating the optimum transmission channel rate to the public communication network side, a cumulative value is obtained from the cumulative value of the data amount obtained for each data type shown in the first embodiment described above. The transmission channel rate for each data type may be selected by performing division by the calculated time and converting to an effective rate per unit time for each data type.

Further, the ratio of the amount of data for each data type to the cumulative value of the amount of data obtained for each data type shown in the first embodiment is calculated, and all the data on the public communication network side are calculated. The transmission channel rate for each data type may be selected according to the ratio of the data amount for each data type to the fixed transmission rate of the channel.

Further, with respect to the remaining amount of data in the buffer for each data type shown in the second embodiment,
Calculate the ratio of the remaining data amount for each data type, and select the transmission channel rate for each data type according to the ratio of the remaining data amount for each data type to the fixed transmission rate of all channels on the public communication network side. You may In this case, the transmission rates of all channels on the public communication network side can be made variable according to the increase or decrease of the remaining amount of data in the buffer for each data type.

Generally, since the channel rate of voice data is often fixed depending on the voice encoding side, the transmission channel rate of a certain data type is fixed and the transmission channel rate of another data type is switched. It may be configured as follows.

[0055]

As described above, according to the present invention, according to the present invention, the packet data received from the LAN side according to the data amount for each data type and the data remaining amount in the buffer for each data type can be Since the optimum transmission channel rate is assigned to the communication network side, it is possible to perform efficient transfer corresponding to the change in the transmission data amount for each data type.

Further, according to the feature of the present invention, the optimum amount for the public communication network side is determined according to the data amount for each data type of the packet data received from the LAN side and the remaining amount of data in the buffer for each data type. Since it is configured to allocate the transmission channel rate, the terminal connected to the LAN transmits differently depending on whether it communicates with the terminal connected to the public communication network or when it communicates with the terminal connected to the LAN. There is no need to perform control, and it is possible to achieve the effect that data transfer can be performed while utilizing the transfer rate of the LAN as effectively as possible without depending on the transfer rate of the public communication network.

Further, according to the feature of the present invention, the optimum amount for the public communication network side is determined according to the data amount of each packet type received from the LAN side and the remaining amount of data in the buffer for each data type. Since it is configured to allocate the transmission channel rate, when realizing multipoint communication, it is not necessary for the gateway device to perform complicated flow control using a plurality of buffers corresponding to each point. It is possible to prevent cost increase.

Further, according to another feature of the present invention, since the transmission channel rate is switched to the public communication network side in accordance with a switching instruction from the outside, the optimum transmission to the public communication network side is performed. Channel rate allocation can be controlled externally.

Further, according to another feature of the present invention, the optimum transmission channel rate is assigned to the public communication network side in accordance with the timer notification of the constant time interval performed by the timer means. The procedure for assigning the optimum transmission channel rate can be automatically started at the timing of a predetermined time interval.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an entire communication system including a gateway device according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing a packet data monitoring procedure in the gateway device according to the first embodiment of the present invention.

FIG. 3 is a flowchart showing a transmission channel rate allocation procedure in the gateway device according to the first embodiment of the present invention.

FIG. 4 is a configuration diagram of an entire communication system including a gateway device according to a second embodiment of the present invention.

FIG. 5 is a flowchart showing a packet data storage procedure in the gateway device according to the second embodiment of the present invention.

FIG. 6 is a flowchart showing a transmission channel rate allocation procedure in the gateway device according to the second embodiment of the present invention.

[Explanation of symbols]

 101, 401 ISDN 102, 402 LAN 111, 411 ISDN terminal 121, 421 Gateway device 122, 422 Line control unit 123, 423 LAN control unit 124, 424 System control unit 125, 425 Memory 126 Packet data identification means 127 Data amount calculation means 426 Packet data storage means 427 Data remaining amount detection means 128,428 Channel rate allocation means 131-133, 431-433 LAN terminal

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Claims (4)

[Claims] 1. A gateway device which is respectively connected to a public communication network and a LAN via a communication line and performs a communication protocol conversion between the public communication network side and the LAN side, and receives from the LAN side. Packet data identification means for identifying the data type and data size of packet data to be transmitted to the public communication network side, and for each data type based on the data type and data size of the packet data identified by the packet data identification means And a channel rate allocating means for allocating an optimum transmission channel rate to the public communication network side according to the data amount for each data type calculated by the data amount calculating means. A gateway device having. 2. A gateway device, which is connected to a public communication network and a LAN via a communication line and performs a communication protocol conversion between the public communication network side and the LAN side, receiving from the LAN side. Storage means for storing packet data to be transmitted to the public communication network side in a buffer designated for each data type, and data for detecting the remaining amount of data in the buffer for each data type in which the packet data is stored by the storage means A gateway device comprising: a remaining amount detecting unit; and a channel rate assigning unit that assigns an optimum transmission channel rate to the public communication network side in accordance with the remaining amount of data detected by the remaining data amount detecting unit. . 3. A switching instruction means for externally instructing switching of the transmission channel rate to the public communication network side is further provided, and the channel rate allocation means is externally performed via the switching instruction means. An optimum transmission channel rate is assigned to the public communication network side in accordance with a switching instruction.
Or the gateway device according to any one of 2 above. 4. Further comprising timer means for notifying a certain time interval, said channel rate assigning means,
The gateway device according to any one of claims 1 to 3, wherein an optimal transmission channel rate is assigned to the public communication network side in accordance with a timer notification given by the timer means.