JPH10111789A - Data reception device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To store a reception packet in a data file means without a trouble even if the write processing rate of the data file means storing reception packet data is comparatively slow. SOLUTION: In the device, a reception means 3 receives packet data transmitted through a line 2 and it is temporarily stored in a buffer means 4. Then, data is stored in the data file means 7 whose writing processing rate of packet data to a file is slower than a rate for receiving packet data from the line 2. Namely, the buffer means 4 has two areas 4A and 4B which temporarily store received packet data. When one area 4A becomes full by packet data, a buffer management means 5 changes the area for storing reception packet data to the other area 4B based on packet data quantity which the respective areas store and writes packet data stored in the area 4A into the data file means 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data receiving apparatus for receiving packetized data and storing it in a file, and more particularly to a data receiving apparatus in which a packet data receiving rate exceeds a file writing rate. The present invention also relates to a data receiving apparatus capable of writing received packet data to a file without any problem.

[0002]

2. Description of the Related Art For example, in a security information distribution system,
From the data transmission center, securities information is transmitted as packet data to each store. Each store stores the received packet data in a data file means such as a hard disk device, and stores the securities information as necessary. Processing (for example, display output) is performed. In such a system, a relatively large amount of packet data having a relatively small amount of data is continuously transmitted from a data transmission source, and the data receiving side (that is, a data receiving apparatus) sequentially receives these packet data and transmits Must be stored in

In such a data receiving apparatus which continuously receives a large number of packets and stores it in a file, if the data file means is constituted by a storage device having a relatively low write processing speed, such as a hard disk device, ,
The timing at which packets are received is earlier than the timing at which they are written to a file, and all received packet data cannot be stored in a file.

[0004] For example, 9600
A hard disk which takes 180 ms to perform a write process including a series of processes such as file open, data read, data change, data write, and file close as data file means for continuously transferring data over a bps line and storing these packet data. When the device is used, each packet data has a size of 216 bytes or more, which causes a delay in the writing process. That is, 172 from the 9600 bps line to 180 ms
Since 8 bits (216 bytes) of data are received, if each packet is less than 216 bytes,
Before the writing process for one packet data is completed, subsequent packet data is received, and the writing process cannot be completed in time for receiving the packet data.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional circumstances, and is intended to receive packet data even when the write processing rate of a data file means for storing received packets is relatively low. It is an object of the present invention to provide a data receiving apparatus capable of storing received packets in a data file means without any problem regardless of the rate.

[0006]

In order to achieve the above object, in a data receiving apparatus according to the present invention, packet data transmitted via a line is received by a receiving means, and the received packet data is buffered. After that, the packet data is written into the data file unit at a rate at which the packet data is written to the file at a lower rate than the rate at which the packet data is received from the line.

More specifically, the buffer means has at least two areas for temporarily storing the received packet data, and the buffer management means makes a decision based on the amount of packet data stored in each of these areas. It manages storing packet data in each area and writing packet data from each area to a file. That is, the buffer management means changes the area for storing the received packet data to another area when one area is filled with packet data, and also converts the packet data stored in the one area to a file. Perform the process of writing to

Therefore, under this management processing, the storage means stores the received packet data in the area of the buffer means designated by the buffer management means, and the writing means stores the packet data in the area of the buffer means designated by the buffer management means. The stored packet data is written to a file in the data file means, and the received packet data is stored in the data file means without loss.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A data receiving apparatus according to one embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a configuration of a data receiving apparatus according to the present embodiment. The data receiving device includes a receiving unit 3 for receiving packet data from the data transmission center 1 via the line 2, and two areas 4A and 4B for temporarily storing the packet data.
Buffer means 4 having (A side, B side), and buffer management means for managing storage of packet data in each area 4A, 4B of buffer means 4 and writing of packet data from each area 4A, 4B to a file 5, storage means 6 for storing the packet data received by the receiving means 3 in one of the areas (surface A or surface B) designated by the buffer management means 5, and finally storing the received packet data as a file Data file means 7 for holding;
A writing unit 8 for writing packet data stored in any of the areas (surface B or surface A) designated by the buffer management unit 5 into a file of the data file unit 7.

Here, the line 2 may be either a wired line or a wireless line, and the receiving means 3 performs necessary demodulation processing on the packet data sent via the line and sequentially receives the data. The buffer means 4 is composed of a memory having a high access speed such as a RAM, and is provided with remaining area counters 4AC and 4BC for indicating the remaining amount (empty amount) of the data storage areas 4A and 4B. Have been.

The buffer management means 5 updates the remaining area counters 4AC and 4BC, and based on the amount of packet data stored in each of the areas 4A and 4B indicated by the values of the remaining area counters 4AC and 4BC. , And manages storage of packet data in each area and writing of packet data from each area to the file 7. That is, when one area is filled with packet data, the buffer management means 5 causes the storage means 6 to change the area for storing the received packet data to another area, and to store the received packet data in the one area. The written packet data is written to the data file means 7 by the writing means 7. Note that the buffer management means 5
U is configured by executing a program, and executes the management processing described above.

The storage means 6 performs a process of sequentially writing the packet data sequence received by the receiving means 3 to the buffer means 4, and which of the areas 4 A and 4 B of the buffer means 4 is written in accordance with an instruction from the buffer management means 5. The writing unit 8 performs a process of sequentially reading the packet data stored in the buffer unit 4 and writing the packet data in the data file unit 7.
Whether to read the packet data from B follows the instruction from the buffer management means 5. The data file means 7 is constituted by a hard disk device (external storage device), and the rate at which the receiving means 3 receives packet data from the line 2 is faster than the rate at which packet data is written to the hard disk device 7. ing.

Next, the packet data reception and filing processing performed by the data receiving apparatus having the above-described configuration will be described.
This will be described with reference to the flowchart shown in FIG. First,
When the data receiving apparatus is started, the buffer management unit 5 manages the buffer unit 4 (information indicating which one of the areas 4A and 4B is currently used for storage, and the remaining area counters 4AC and 4BC). Value). Then, initially, the buffer management means 5 sets the buffer area 4A on the A side for storing the received packet data, and initializes the value of the remaining area counter 4AC of the area (100% free). (Step S1).

Next, the data receiving apparatus enters a packet data reception waiting state (step S2). When the receiving means 3 receives the packet data via the line 2, the buffer management means 5 sets the size (data amount) of the received packet. ) Is compared with the value of the remaining area counter 4AC to determine whether or not the received packet data can be stored in the currently used area (Side A) (step S3). As a result of this determination, if there is a remaining area for storing the received packet data in the currently used area 4A, the buffer management unit 5
Causes the storage unit 6 to store the received packet data in the area 4A (step S4), and updates the value of the received packet storing the value of the remaining area counter 4AC by subtracting the size of the received packet (step S5).
The subsequent processing is repeated.

On the other hand, as a result of the above determination, if there is not enough remaining area for storing the received packet data in the currently used area 4A, the buffer management means 5 can store the received packet data in the remaining area. Storing part 6
Is stored in the currently used area 4A (step S6). Then, the buffer management unit 5 sets the area used for storing the received packet data to another area (B side) 4B.
And the value of the remaining area counter 4BC of this area is initialized (100% free) (step S).
7). Then, the buffer management unit 5 sends an instruction request to the writing unit 8 by designating the area 4A on the side A where the received packet data is fully stored (step S8), and returns all the received packet data stored in the area 4A. Is written to the file of the data file means 7.

The buffer management means 5 causes the storage means 6 to store the remaining portion of the received packet data, which could not be stored in the area 4A, in the area 4B on the side B (step S9), and the value of the remaining area counter 4BC. Is updated to a value obtained by subtracting the size of the packet data storing (step S10), and the processing from step S2 is repeated. As described above, even while the packet data stored in one area is being written to the data file means 7 and the subsequent packet data received is stored in another area, the packet data that is continuously received is stored. Columns can be stored in the data file means 7 without dropping.

The capacity of each of the areas 4A and 4B is determined on the basis of the amount of packet data received during the writing process to the data file means 7. For example, when writing to the data file
ms, and if the device is set to receive 216 bytes of packet data during this time, each area 4A, 4B
Is set to 216 bytes or more, the received packet data can be stored in the data file means 7 without being missed. In the above example, two areas for temporarily storing received packet data are provided, but three or more areas may be provided in the present invention. In this case, if area switching control is performed, Even if the capacity of each area is set smaller than the case of two, it is possible to store the received packet data in the data file means 7 without dropping.

[0018]

As described above, according to the present invention,
Even when the write processing rate of the data file means for storing the received packet data is relatively slow, the received packet data can be stored in the data file means without any problem regardless of the packet data reception rate.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating a data receiving apparatus according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating a procedure of a data receiving process according to an embodiment of the present invention.

[Explanation of symbols]

2 ... line, 3 ... receiving means, 4 ... buffer means, 4A, 4B ... area, 5 ... buffer management means, 6 ... storage means, 7 ... data file means 8 writing means,

Claims (1)

[Claims] 1. A data receiving apparatus for storing received packet data in a file, a receiving means for receiving the packet data via a line, and a processing rate for writing the packet data to the file, the rate for receiving the packet data from the line. Slower data file means, buffer means having at least two areas for temporarily storing received packet data, and packet data to each area based on the amount of packet data stored in each area of the buffer means. Management means for managing storage of packet data and writing of packet data from each area to a file; storage means for storing packet data received by the reception means in an area of the buffer means designated by the buffer management means; and buffer management means. Area of the buffer means indicated by Writing means for performing writing processing on packet data stored in the data file means in a file of the data file means, wherein the buffer management means stores the received packet data when one area is full of packet data. A data receiving apparatus for changing an area to be copied to another area and writing packet data stored in the one area to a file.