JP2812311B2 - ATM network access device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ATM network access device, and more particularly to an ATM device having a multiplexing function.
(Asynchronous Transfer Mo
de) An access device for efficiently connecting to a network.

[0002]

2. Description of the Related Art At present, in a time division multiplexing apparatus which performs time division multiplexing, data on a plurality of transmission paths are fixedly assigned to time slots for multiplexing. That is, the conventional time-division multiplexing apparatus includes a multiplexing apparatus 21 and an ATM cell forming unit 22, as shown in FIG.

[0003] Data "T1" and "T2" transmitted on the transmission path 200, data "D1" to "D4" transmitted on the transmission path 201, and transmission on a transmission path 202. Each of the data "V1" to "V4" is fixedly assigned to a time slot in the multiplexing device 21 and transmitted to the multiplexing side transmission path 2-3.

[0004] In this case, for example, even if the data (data "T1", "T2" or data "V1" to "V4") transmitted on the transmission lines 200 and 202 is actually data without information. In the multiplex transmission path 203, time slots are fixedly assigned to such data.

[0005] Since multiplex transmission data has a fixed speed, A
The ATM cell conversion is performed by the AAL Type (ATM adaptation layer type 1) in the TM cell conversion unit 22. Therefore, the transmission path 20 which is data without information
Up to data on 0,202 will be accommodated in the information field of the ATM cell. Here, AAL Type
For details, see {TU-T Recommendations}. 363.

[0006]

In the conventional time-division multiplexing apparatus described above, data on a transmission line is stored in an information field of an ATM cell regardless of the presence or absence of the information. When the data without the data is transmitted, the ATM cell is output without a valid cell in the information field, and extra traffic is transmitted to the network.

Accordingly, an object of the present invention is to solve the above-mentioned problems, improve transmission efficiency without sending unnecessary traffic to the network, and make it possible to easily use a wideband network easily. AT that can be
M network access device.

[0008]

SUMMARY OF THE INVENTION An ATM network access apparatus according to the present invention comprises: audio encoding means for encoding an audio signal and outputting the encoded signal to a fixed-speed first line; Video encoding means for outputting to a second line, a buffer memory for temporarily storing burst data and outputting to a third line of a fixed speed, data on the first line and data on the second line Multiplexing means for multiplexing the data multiplexed with the data on the third line, cell multiplexing means for converting the data multiplexed by the multiplexing means into ATM cells and transmitting the data, and data on the first line. First detecting means for detecting whether or not data exists; second detecting means for detecting whether or not data exists on the second line; and data for detecting whether or not data exists on the third line. Third detection method for detecting whether or not to perform And controlling whether or not to execute the ATM cell conversion by the cell conversion unit based on the detection result of the first detection unit, the detection result of the second detection unit, and the detection result of the third detection unit. Control means for performing the operation.

Another ATM network access apparatus according to the present invention comprises: audio encoding means for encoding an audio signal and outputting the encoded signal to a fixed-speed first line; and encoding the video signal to a fixed-speed second line. A video encoding means for outputting, a buffer memory for temporarily storing burst data and outputting the burst data to a third line of a fixed speed, a means for transferring at least communication data including a facsimile signal to another line of a fixed speed, Multiplexing means for multiplexing data on a first line, data on the second line, data on the third line, and data on the other line; Celling means for converting the converted data into ATM cells and transmitting the data, first detecting means for detecting whether or not data exists on the first line, and data existing on the second line Or Second detecting means for detecting whether data exists on the third line, third detecting means for detecting whether data exists on the third line, and detecting whether data exists on the other line. A fourth detection unit, a detection result of the first detection unit, a detection result of the second detection unit,
Control means for controlling whether or not to execute the ATM cell conversion by the cell conversion means based on the detection result of the detection means and the detection result of the fourth detection means.

As described above, an interface capable of directly accommodating an existing device (terminal) is provided, and line data of different speeds by this interface are multiplexed into time slots assigned in advance, and whether there is transfer information in the line data is determined. Is detected by the detecting means, and when it is detected that there is no transfer information in all the line data, the conversion of the time slot into the ATM cell is stopped.

As a result, it is possible to connect to an ATM network without requiring a special device, and it is possible to avoid sending unnecessary ATM cells having no transfer information.

[0012]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of one embodiment of the present invention. In the figure, an ATM network access apparatus according to one embodiment of the present invention includes an audio encoding unit 1, a video encoding unit 2, a data buffer 3, valid information detecting units 4 to 6, a multiplexing unit 7, an ATM cell, Transformation part 8
And a celling control unit 9.

The audio encoding unit 1 performs digital conversion of the input analog audio information, and the video encoding unit 2 performs digital conversion of the input analog video information. The data buffer 3 is for temporarily storing digital data from a computer or the like (not shown), and has a storage function for transmitting burst data from the computer to a fixed speed line, thereby preventing loss of information.

The transmission paths 101 to 103 are respectively audio, video,
It is a data transmission path for data and is a fixed-speed line. These transmission lines 101 to 103 are connected to a multiplexing unit 7 via valid information detecting units 4 to 6.

The valid information detectors 4 to 6 detect whether actual data is flowing on the transmission lines 101 to 103, which are fixed speed lines, and detect that the data is flowing. T-on signal 111 and V-on
The signal 112 and the D-on signal 113 are sent to the celling control section 9 to cause the corresponding time slot to be cellized.

The multiplexing unit 7 multiplexes line data of different speeds (data on the transmission lines 104 to 106) into continuous time slots reserved for each line to generate high-speed multiplex transmission data 107.

The celling control section 9 controls which time slot of the multiplex transmission data 107 is converted into an ATM cell.
A TL (control) signal 109 is sent to the ATM cell unit 8. The ATM cell forming unit 8 receives the instruction from the cell forming control unit 9 and distinguishes the corresponding time slot from the logical number by AA.
Perform ATM cell conversion according to L Type.

FIG. 2 is a block diagram showing a detailed configuration of the ATM cell unit 8 of FIG. In the figure, an ATM cell unit 8 includes a frame detecting unit 81 and an effective slot identifying unit 82.
And AAL (ATM adaptation layer) processing unit 8
And 3.

The frame detecting section 81 outputs the multiplex transmission data 10
7 and detects the location of the time slot in the frame. The effective slot identification unit 82 identifies which time slot is to be converted into an ATM cell based on the CTL signal 109. The AAL processing unit 83 converts the corresponding slot into an ATM cell according to the AAL Type (ATM adaptation layer type 1).

FIG. 3 is a timing chart showing the operation of one embodiment of the present invention. The operation of forming an ATM cell according to an embodiment of the present invention will be described with reference to FIGS.

Referring to FIG. 3, the audio signal 101, which is a digital signal from the audio encoder 1, and the data signal 103 from the data buffer 3 do not contain actual data during the time T. During the time T, the video encoding unit 2
The video signal 102, which is a digital signal from, is stored in a time slot.

At this time, since only the valid information detecting section 5 detects that data is flowing, the V-on signal 11
Only 2 turns on. The T-on signal 111, the V-on signal 112, and the D-on signal 113 from each of the valid information detection units 4 to 6 are transmitted to the celling control unit 9, and the celling control unit 9 generates the CTL signal 109. I do. This CTL signal 109 is output from an unshown AND circuit.

The ATM cell unit 8 generates the CTL signal 109
And converts the corresponding time slot into an ATM cell by AA
The cell is formed by L Type1. That is, based on the location of the time slot in the frame of the multiplex transmission data 107 grasped by the frame detecting section 81, the effective slot identifying section 82 identifies which time slot is to be converted into an ATM cell by the CTL signal 109. The AAL processing unit 83 converts the time slot identified by the valid slot identification unit 82 into an ATM cell according to the AAL Type.

FIG. 4 is a block diagram showing the configuration of another embodiment of the present invention. In another embodiment of the present invention, in addition to the configuration of the embodiment of the present invention shown in FIG. 1, other interfaces 10-1 to 10-n [other communication data such as facsimile (FAX)] ] To improve the bandwidth utilization rate of the network.

These interfaces 10-1 to 10-n
Represents an audio signal 101, a video signal 102, and a data signal 1
Communication data other than 03 is transferred on the transmission lines 120-1 to 120-n which are fixed speed lines.

The interfaces 10-1 to 10-1
0-n are provided corresponding to the valid information detecting units 11-1 to 11-n, and the valid information detecting units 11-1 to 11-n are provided on the transmission lines 120-1 to 120-n. It is detected whether data is flowing, and when it is detected that data is flowing, the on signals 122-1 to 122-
n is sent to the celling control unit 9 to cause the corresponding time slot to be cellized.

However, the interfaces 10-1 to 10-n
If the actual information communication is not performed even if
Cell information in the TM network is not transferred.

The multiplexing unit 7 multiplexes line data of different speeds (data on the transmission lines 104 to 106 and 121-1 to 121-n) into continuous time slots reserved for each line, and performs high-speed multiplex transmission. The data 107 is generated.

The celling control section 9 controls which time slot of the multiplex transmission data 107 is to be converted into an ATM cell.
A TL (control) signal 109 is sent to the ATM cell unit 8. The ATM cell forming unit 8 receives the instruction from the cell forming control unit 9 and distinguishes the corresponding time slot from the logical number by AA.
Perform ATM cell conversion according to L Type.

As described above, the data lines (transmission lines 104 to 106, 121-1 to 121-)
n), the validity information detectors 4 to 6 and 11-1 to 11-n are caused to function, and the A of the ATM cell forming unit 8 is controlled by the cell forming control unit 9.
Since this is reflected in the control for the conversion to the TM cell, unnecessary ATM cells having no transfer information need not be transmitted to the network, and communication utilizing the network interface to some extent can be fully utilized.

Multiplexing of the existing line is facilitated by multiplexing at the preceding stage of the ATM cell forming unit 8, that is, by the multiplexing unit 7. AM without arranging
Access to the T network can be applied.

[0032]

As described above, according to the present invention, an audio signal and a video signal are encoded and output to a fixed-speed line, respectively, and burst data is temporarily stored in a buffer memory before being sent to a fixed-speed line. In addition to outputting the data and multiplexing the data on these lines respectively,
The transmission efficiency can be improved without sending unnecessary traffic to the network by controlling whether or not to execute ATM cell based on the detection result of whether or not data exists on each of these lines. Thus, there is an effect that the broadband network can be easily and sufficiently used.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

FIG. 2 is a block diagram showing a detailed configuration of an ATM cell unit shown in FIG. 1;

FIG. 3 is a timing chart showing the operation of one embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of another embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration of a conventional example.

[Explanation of symbols]

 Reference Signs List 1 audio encoding unit 2 video encoding unit 3 data buffer 4 to 6, 11-1 to 11-n valid information detection unit 7 multiplexing unit 8 ATM cell conversion unit 9 cell conversion control unit 10-1 to 10-n interface 81 Frame detection unit 82 Effective slot identification unit 83 AAL processing unit

Claims (4)

(57) [Claims] 1. An audio encoding means for encoding an audio signal and outputting it to a fixed-speed first line, a video encoding means for encoding a video signal and outputting it to a fixed-speed second line,
A buffer memory for temporarily storing burst data and outputting the burst data to a fixed-speed third line; and a buffer memory for storing data on the first line, data on the second line, and data on the third line, respectively. Multiplexing means for multiplexing, cell conversion means for converting the data multiplexed by the multiplexing means into ATM cells and transmitting the data, and a first means for detecting whether or not data exists on the first line. Detecting means, second detecting means for detecting whether data exists on the second line, and third detecting means for detecting whether data exists on the third line The detection result of the first detection means and the second detection result
Control means for controlling whether or not to execute said ATM cell conversion by said cell conversion means based on a detection result of said detection means and a detection result of said third detection means. . 2. The system according to claim 1, wherein said celling means includes identification means for identifying an effective slot to be converted into an ATM cell based on control information from said control means.
TM network access device. 3. An audio encoding means for encoding an audio signal and outputting it to a fixed-speed first line, a video encoding means for encoding a video signal and outputting it to a fixed-speed second line,
A buffer memory for temporarily storing burst data and outputting the data to a third line of a fixed speed, means for transferring at least communication data including a facsimile signal to another line of a fixed speed, and data on the first line. Multiplexing means for multiplexing the data on the second line, the data on the third line, and the data on the other line, and converting the multiplexed data into ATM cells. Means for transmitting data on the first line, first detecting means for detecting whether data exists on the first line, and second detecting means for detecting whether data exists on the second line. 2 detecting means;
A third detection unit for detecting whether data exists on the third line, a fourth detection unit for detecting whether data exists on the other line, Based on the detection result of the detection means, the detection result of the second detection means, the detection result of the third detection means, and the detection result of the fourth detection means. Control means for controlling whether to execute the ATM network. 4. The system according to claim 3, wherein said cell-forming means includes identification means for identifying an effective slot to be converted into an ATM cell based on control information from said control means.
TM network access device.