JPH09247208A - Packet communication processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To conduct real time communication without accumulated delay or interruption of data by discriminating the duration of a congestion time of a reception buffer, aborting reception packets in excess when the time is long and not avoiding reception packets by excess tentatively. SOLUTION: A congestion discrimination section 109 compares a congestion time obtained by inquiring about a congestion consecutive time in a reception buffer section 102 of a congestion time measurement section 108 with a congestion discrimination time acquired by inquiring of a congestion discrimination time setting section 110. Then stored packets in excess of a congestion detection start number among packets stored in the reception buffer section 102 are all aborted when the congestion time is in excess of the congestion discrimination time. When the congestion time is less than the congestion discrimination time, even when number of packets stored in the reception buffer section 102 exceeds a congestion start number, the packets are not aborted but stored. Thus, data subject to decoding processing are continuous.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packet communication processing device, and more particularly to a local area network (hereinafter, LAN).
The present invention relates to a technique effective when applied to a packet communication processing device that decodes a packet including video and audio data received via the like) in real time and outputs it as video and audio.

[0002]

2. Description of the Related Art In a conventional packet communication processing device, an LA
In order to suppress the influence of fluctuations in the transmission / reception interval on the network, which is a characteristic of N, packets exchanged on the LAN are buffered for communication to prevent data interruption.

Further, in order to reduce loss of data due to discard of packets when overflowing from a buffer at the time of packet reception, retransmission control is performed to improve data communication quality.

[0004]

SUMMARY OF THE INVENTION As a result of studying the above prior art, the present inventor has found the following problems.

[0005] In the communication using LAN, the data system mainly sporadically and the accuracy of which is required more than the processing time has dominated most of the history, and the buffer capacity has been increased and the retransmission function has been strengthened.

However, in recent years, bidirectional communication of video and audio is increasing even on a LAN, and it is necessary to continuously process the video information and audio information in real time, unlike data communication.

Therefore, as in the conventional case, when the buffer is made larger, a delay is caused by the buffered amount, and the real-time property is lacking. On the contrary, the buffer is made smaller to increase the real-time property. Go, L
Affected by the fluctuations peculiar to AN, video and audio will be interrupted, and discarding will occur frequently due to buffer overflow.
There was a problem that breaks in video and audio would frequently occur.

[0008] Further, when the resending function is incorporated, there is a problem that video and audio are surely reproduced, but lack in real-time property, and if network quality is poor, a great delay occurs. .

Therefore, the present invention has been made to solve the above problems, and an object thereof is to perform real-time data decoding of a packet containing video and audio data received via a LAN. It is an object of the present invention to provide a technology capable of performing real-time communication without causing accumulated delay or data interruption in a real-time packet communication processing device that outputs video or audio.

The above and other objects and novel features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

[0011]

SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, the outline of a representative one will be briefly described.
It is as follows.

A reception buffer for receiving a packet containing video and audio data via a network, a data decoding processing means for decoding the packet in the reception buffer in real time, and the decoded data for the video and audio. In a packet communication processing device having an output device for outputting as, a congestion detection start number setting means for setting the number of received packets as a threshold value for starting detection of whether or not the reception buffer is in a congestion state, and the reception buffer Congestion determination time setting means for setting a time to be a threshold value for determining the length of the congestion time, if the number of packets accumulated in the reception buffer exceeds the threshold value set by the congestion detection start number setting means, Congestion time measuring means to measure the duration of the state of exceeding, the duration measured by the congestion time measuring means It is determined whether it is longer or shorter than the threshold set by the congestion determination time setting means, and if the duration is longer than the threshold, discard received packets for the amount exceeding the threshold set by the congestion detection start number setting means. If the duration is shorter than a threshold value, the reception buffer is instructed not to discard the received packets for the amount that temporarily exceeds the threshold value set by the congestion detection start number setting means. A buffer control unit including a congestion determination unit is provided.

[0013]

FIG. 1 is a diagram showing a hardware configuration of a packet communication processing device according to an embodiment of the present invention. Note that FIG. 1 shows only the hardware configuration related to packet reception, and the hardware configuration related to transmission is omitted.

In FIG. 1, 100 is a LAN, 101 is a LAN interface unit, 102 is a reception buffer unit, and 10 is a unit.
3 is a data decoding processing unit, 104 is an output device, 105 is an input unit A, 106 is a reception buffer control unit, 107 is a congestion detection start number setting unit, 108 is a congestion time measuring unit, 109 is a congestion determination unit, and 110 is congestion. A determination time setting unit, 111 is an input unit B, and 112 is a packet communication processing device, respectively.

In the packet communication processing device 112 of the present embodiment shown in FIG. 1, a LAN interface section 101 for taking in a packet received via the LAN 100 and a receiving buffer section 1 for temporarily accumulating the taken-in packet.
02, a data decoding processing unit 103 that decomposes the accumulated packets and decodes the coded data, an output device 104 that outputs the decoded data, and a reception that controls the reception buffer unit 102. Buffer control unit 10
6 is provided.

The reception buffer control unit 106 comprises a congestion detection start number setting unit 107, a congestion time measuring unit 108, a congestion determination unit 109, and a congestion determination time setting unit 110.

The congestion detection start number setting unit 107 stores a constant set from the input unit A105, and this value becomes the congestion detection start number.

The congestion time measuring unit 108 inquires of the reception buffer unit 102 about the number of accumulated packets in the reception buffer unit 102, and the congestion detection start number setting unit 107. When the number of accumulated packets in the reception buffer unit 102 exceeds the congestion detection start number, the number of accumulated packets in the reception buffer unit 102 continues while the number exceeds the congestion detection start number. Measure time.

In the congestion judgment time setting unit 110, the congestion judgment time, which is a reference value for judging whether the congestion time in the reception buffer unit 102 is long or short, is set and stored from the input unit B111.

The congestion determination unit 109 is a congestion time measurement unit 10
8, the congestion time obtained by inquiring the congestion duration time in the reception buffer unit 102 and the congestion determination time obtained by inquiring the congestion determination time setting unit 110 are compared, and the congestion time is determined as the congestion determination time. Is exceeded,
Of the packets accumulated in the reception buffer unit 102, all accumulated packets exceeding the congestion detection start number are discarded, and when the congestion time does not reach the congestion determination time, the accumulation is performed in the reception buffer unit 102. Even if the number of packets that have exceeded the congestion detection start number is exceeded, these packets are retained without being discarded.

Next, the reception buffer control section 106 described above.
Will be described.

FIG. 2 is a flow chart for explaining the operation of the reception buffer control unit in the packet communication processing device of this embodiment.

First, the congestion detection start number is set in the congestion detection start number setting unit 107 by the input unit A105 (step 3).
01), and the congestion determination time is set in the congestion determination time setting unit 110 by the input unit B111 (step 302).

Then, the congestion time measuring unit 108 inquires and obtains the number of packets stored in the receiving buffer unit 102 and the result obtained by inquiring the congestion detection start number setting unit 107 is compared ( Step 30
3) If the number of packets stored in the reception buffer unit 102 exceeds the congestion detection start number, the reception buffer unit 10
The duration is measured while the number of stored packets in 2 exceeds the congestion detection start number (step 304).

Thereafter, the congestion judgment unit 109 compares the congestion duration time acquired by inquiring the congestion time measurement unit 108 with the congestion judgment time acquired by inquiring the congestion judgment time setting unit 110 (step 305), When the duration exceeds the congestion determination time, the congestion determination unit 109 discards all the accumulated packets exceeding the congestion detection start number among the packets accumulated in the reception buffer unit 102 (step 306). ).

When the congestion duration time is less than the congestion determination time, even if the number of packets accumulated in the reception buffer unit 102 exceeds the congestion detection start number, the packets are retained without being discarded (step 307).

As described above, when the congestion duration time exceeds the congestion determination time, all accumulated packets exceeding the congestion detection start number are discarded so that the packets accumulated in the reception buffer unit 102 are used. When the accumulated delay is eliminated and the congestion duration time is less than the congestion determination time, even if the number of packets accumulated in the reception buffer unit 102 exceeds the congestion detection start number, they can be retained without being discarded. The data to be decoded is continuous.

Next, an embodiment will be described in which the received packets accumulated in the reception buffer unit 102 are not passed to the data decoding processing unit 103 in sequence, but are passed after being collected in a predetermined number, and buffer control for preventing data interruption is performed. explain.

FIG. 3 is a diagram showing a hardware configuration of a packet communication processing device according to another embodiment of the present invention. Note that FIG. 3 similarly shows only the hardware configuration related to packet reception, and omits the hardware configuration related to transmission.

As shown in FIG. 3, the packet communication processing device of the present embodiment is the packet communication processing device 1 shown in FIG.
12, a decoding start number setting unit 213 and its input unit C21
4 and the buffer management unit 215 are added.

The decoding start number setting unit 213 sets the decoding start number which is a trigger for passing the accumulated packets from the reception buffer to the data decoding processing unit 103.

The decoding start number is a value input from the input unit C214, and the decoding start number setting unit 213 is a result obtained by sequentially inquiring the reception buffer unit 102 about the number of accumulated packets. Compare with the decoding start number,
Every time the number of accumulated packets exceeds the decoding start number, the accumulated packets are passed to the data decoding processing unit 103.

As a result, even if the packet arrival from the LAN is delayed, the data decoding process can be continuously performed while the packet is held in the reception buffer unit 102, and the data interruption can be prevented. .

Further, this is effective mainly against fluctuations in packet reception intervals on the LAN, which is a problem when the packet reception processing from the LAN is started, but the packet arrival time is also congested on the LAN. When the number of received packets is sparse and the number of received packets is small, the frequency of data interruption can be reduced, and discontinuity of decoded data due to delay of packet arrival time can be prevented.

Further, in the buffer management unit 215,
The number of stored packets in the reception buffer unit 102 is monitored at every specific period t (set arbitrarily), and the result is used to store the number of stored packets based on a statistic such as an average during a time T that can be set arbitrarily. Immediately after calculating, the decoding start number setting unit 213 is immediately inquired to compare the decoding start number with the accumulated packet number based on the statistic, and (1) when the accumulated packet number exceeds the decoding start number. Immediately reduces the number of decoding starts by n (arbitrarily set).

(2) If the number of accumulated packets does not exceed the decoding start number, immediately increase the decoding start number by m (arbitrarily set).

(3) When the number of accumulated packets is equal to the decoding start number, the decoding start number is left unchanged, and the comparison and determination processing of (1), (2) and (3) is performed at time T.
This is repeated for each unit time, that is, for each unit time when the buffer management unit 215 calculates the number of accumulated packets based on the statistic, and adaptively using the coarse density in the reception buffer unit 102 that reflects the packet transfer status of the LAN network. It is possible to control various reception buffers for the decoded data processing.

This makes it possible to minimize the delay due to the accumulation of received packets and prevent discontinuity in data decoding adaptively to the network conditions.

Therefore, as described above, by determining whether the packet should be discarded or should not be discarded depending on the congestion state in the reception buffer unit, cumulative delay and data interruption can be prevented. Real-time communication can be performed.

Further, by setting the decoding start number in order to take into consideration the fluctuation of the packet reception interval on the LAN, and decoding the collected packets of data, discontinuity of data decoding can be prevented and data interruption can be prevented. It becomes possible to perform real-time communication without occurring.

Further, by monitoring the buffer congestion state and changing the decoding start number according to the situation, the buffer capacity can be controlled, and the cumulative delay and the data interruption can be prevented.

As described above, the invention made by the present inventor is:
Although specifically described based on the embodiment, the present invention
It is needless to say that the present invention is not limited to the above embodiment, and various changes can be made without departing from the scope of the invention.

[0043]

The effects obtained by the representative ones of the inventions disclosed in the present application will be briefly described as follows.

In a real-time packet communication processing device that decodes a packet containing video and audio data received via LAN in real time and outputs it as video and audio, in real time without accumulating delay or data interruption. It becomes possible to communicate.

[Brief description of drawings]

FIG. 1 is a diagram showing a hardware configuration of a packet communication processing device according to an embodiment of the present invention.

FIG. 2 is a flowchart for explaining an operation of a reception buffer control unit in the packet communication processing device of this embodiment.

FIG. 3 is a diagram showing a hardware configuration of a packet communication processing device according to another embodiment of the present invention.

[Explanation of symbols]

100 ... LAN, 101 ... LAN interface section, 1
02 ... reception buffer unit, 103 ... data decoding processing unit, 1
04 ... Output device, 105 ... Input unit A, 106 ... Reception buffer control unit, 107 ... Congestion detection start number setting unit, 108 ...
Congestion time measurement unit, 109 ... Congestion determination unit, 110 ... Congestion determination time setting unit, 111 ... Input unit B, 112 ... Packet communication processing device, 213 ... Decoding start number setting unit, 214 ... Input unit C, 215 ... Buffer management Department.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Hiroshi Watanabe 3-19-3 Nishishinjuku, Shinjuku-ku, Tokyo Inside Nippon Telegraph and Telephone Corporation (72) Yasuhito Hayashi 3-19-2 Nishishinjuku, Shinjuku-ku, Tokyo No. within Nippon Telegraph and Telephone Corporation

Claims (3)

[Claims] 1. A receiving buffer for receiving a packet containing video and audio data via a network, a data decoding processing means for decoding the packet in the receiving buffer in real time, and a video for decoding the decoded data. In a packet communication processing device having an output device for outputting as voice, a congestion detection start number setting means for setting the number of received packets which is a threshold value for starting detection of whether or not the reception buffer is in a congestion state, and Congestion determination time setting means for setting a time to be a threshold for determining the length of congestion time of the reception buffer, and the number of packets accumulated in the reception buffer exceeds the threshold set by the congestion detection start number setting means In, the congestion time measuring means for measuring the duration of the exceeding state, the duration measured by the congestion time measuring means Determines whether it is longer or shorter than the threshold value set by the congestion determination time setting means, and if the duration is longer than the threshold value, discards the received packets in excess of the threshold value set by the congestion detection start number setting means. Is instructed to the reception buffer, and if the duration is shorter than the threshold value, the reception buffer is instructed not to discard the received packets for the time period temporarily exceeding the threshold value set by the congestion detection start number setting means. A packet communication processing device, comprising: a buffer control unit including a congestion determination unit. 2. The packet communication processing device according to claim 1, wherein a decoding start number serving as a threshold value for starting to pass the received packets accumulated in the reception buffer to the data decoding processing means is set, The buffer control means is provided with a decoding start number setting means for instructing the reception buffer to pass the accumulated packets to the data decoding processing means each time the number of accumulated packets in the reception buffer becomes equal to the set threshold value. A packet communication processing device characterized by the above. 3. The packet communication processing device according to claim 2, wherein the number of packets stored in the reception buffer is monitored at predetermined intervals to obtain a statistics of the number of packets stored, and an arbitrary time in the reception buffer is collected. In the range where the average number of accumulated packets exceeds the number of decoding starts, the average number of accumulated packets is calculated, and the number of decoding starts set by the decoding start setting means is compared with the number of average accumulated packets. If there is, the decoding start number is reduced by a predetermined number, and if the average accumulated packet number is within a range not exceeding the decoding start number, the decoding start number is increased by a prescribed number, and the average accumulated packet number starts the decoding. The packet communication processing device, wherein the buffer control means is provided with a buffer management means for keeping the decoding start number as it is in the range equal to the number.