JP3189059B2 - Media-based charging control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a media charging control system in an ATM network. ATM (Asyncronous
Transfer Mode) [Asynchronous transmission mode] is a method for transmitting and receiving audio signals, image signals such as still images and moving images, and various types of data as cells of a fixed length. Since is transmitted in frame units, it is necessary to control the billing for media.

[0002]

2. Description of the Related Art A cell in an ATM network is, for example, shown in FIG.
(A) and an inter-network interface shown in (B), HD is a 5-octet header, and GFC is a basic flow for controlling the flow of traffic generated from each terminal. The control unit, VPI is a logical path identifier, VCI is a logical channel identifier, PT is a payload type for identifying a cell for user information or a cell for network operation, RES is a reserve unit, and CLP is discarded when congestion of voice signal etc. Cell discard priority, which indicates whether the cell enables data discarding or the cell in which data discarding should be avoided as much as possible, HEC indicates a header error correction unit used for header error control and cell synchronization, and IF indicates an information field. Field IF is 48 octets. That is,
The cell is 53 octets long.

[0003] Types 1 to 4 are defined as the SAR protocol (cell format) of the adaptation layer. FIG. 5 shows these types 1-4.
HD is the 5-octet header described above, SN is a 4-bit sequence number, SNP is a 4-bit sequence number protection unit, IF is the information field described above, and IT is 4
Bit information type, LI is 6-bit effective information length, F
EC is a 10-bit related 2-bit error correction code, ST is a 2-bit segment type, RES is a 10-bit reserved field, CRC is a 10-bit cyclic redundancy code, M
ID is a 10-bit multiplex identifier. Therefore, the length of the information field IF differs depending on the types 1 to 4.

[0004] Type 1 is a protocol that supports fixed-rate communication services such as audio signals and image signals.
Type 2 is a protocol that supports communication services such as variable speed audio signals and image signals on the premise of band compression. Type 3 is a protocol supporting a data communication service, and type 4 is a protocol supporting a connectionless data communication service.

[0005] Further, as a general billing system, there is the following. (1) Reservation time charging (2) Location-specific reservation time charging (3) Distance-based charging (4) Pay-as-you-go charging At this stage, no clear proposal has been made for charging in the ATM network. It is (1)-
It is considered that this is realized by any one of the charging methods (4) or a combination thereof. In particular, in the ATM network, since communication is performed in units of cells as described above and cells are discarded in the network during congestion, there is a possibility that the metering method of (4) is adopted as a charging parameter. Is high.

[0006]

SUMMARY OF THE INVENTION As described above, the AT
In the M network, it is conceivable to count the number of cells passing from when a call is generated until it disappears, and use it as a parameter for pay-per-use. In this case, the counted number of cells indicates the amount of information actually transmitted and received between users. In the case of a voice signal or an image signal, cell discarding may occur at the time of congestion in a network, and the quality of a voice or an image is degraded due to the cell discard. That is, since it is found that the number of passing cells and the service quality are in a proportional relationship, it is considered appropriate to use the number of passing cells as a parameter for pay-as-you-go.
However, when data or the like is transmitted via an ATM network, a frame at the layer 2 level is divided into cells for communication. When even one of the divided cells is discarded, the frame is Retransmission control is performed.
Therefore, it is impossible to simply use only the number of passing cells as a parameter for pay-per-use.

The above-mentioned audio signal and image signal are transmitted by cells of type 1 or type 2 in FIG. 5, but are transmitted by type 3 in the case of data. In that case, the data in the cell information field IF is
A segment type ST indicating the beginning, middle, or end of a frame is provided, and a BOM (Begin OfMess) is provided.
age), COM (Center Of Message), EOM (En
d Of Message), SOM (Single Of Message)
Is displayed. On the transmitting side, after dividing the layer 2 frame into cells, the segment type ST is inserted. The sequence number SN cyclically inserts a value from 0 to 15.

On the receiving side, the received cell is assembled into a layer 2 frame. Basically, data is stored in the buffer memory from the BOM segment type ST cell, and the EOM segment type ST cell is stored in the buffer memory. When reception is detected, the layer 2 frame is transferred to the higher-level device. In this case, the sequence number SN is monitored, and if even one of the values assigned cyclically from 0 to 15 is missing, it can be determined that cell discard has occurred. Does not transfer the data stored in the buffer memory to the host device.

[0009] Therefore, the upper-level device sends a retransmission request to the transmitting side because the number of transmitted and received frames does not match or due to a timeout or the like. As a result, the transmitting side again divides the layer 2 frame and performs retransmission control of the cell. Therefore, when simply counting the number of passing cells, for example,
One cell in a frame of 100 cells is discarded, and it is counted that 99 cells have passed. Since this frame is retransmitted, 99 cells are wasteful. However, this is also charged. Therefore, there is a problem that the user is charged even for the wasted cells. The present invention
It is another object of the present invention to count the number of cells that have actually become effective in a communication service that performs retransmission control of data and the like, and use the counted number as a billing-based parameter.

[0010]

The media-based charging control system of the present invention will be described with reference to FIG.
A for transmitting and receiving image signals, data, etc. as cells of a fixed length
Counter unit 1 for counting the number of cells in a TM network
And a cell identification unit 2 for identifying the type of a cell, and a frame detection unit 3 for detecting a frame of data, wherein the cell identification unit 2 does not perform retransmission control between transmission and reception such as an audio signal and an image signal. When the cell of the service is identified, the passing cell of the communication service is counted by the counter unit 1 and used as a usage-based parameter for charging the communication service, and the cell identification unit 2 performs retransmission control between data transmission and reception such as data. When the cell of the service is identified, the frame in the communication service is detected by the frame detection unit 3, and the number of cells in the counter unit 1 is counted only for the frame in which the cell is not discarded. Is used as a usage-based parameter for charging for the communication service.

When a cell of a communication service which performs retransmission control between data transmission and reception is identified by the cell identification unit 2, the segment type and sequence number of the cell are monitored, and the frame detection unit 3 The number of cells from the cell containing the first part of the frame in the information field to the cell containing the last part of the frame in the information field is counted. It is to be added.

When a passing cell is counted by the counter unit 1 and a cell of a communication service for performing retransmission control between transmission and reception such as data is identified by the cell identification unit 2, the segment type and sequence number of the cell are monitored. And
The frame detector 3 counts the number of cells from the cell including the head portion of the frame in the information field to the cell including the end portion of the frame in the information field. When an abnormality is detected, the count value of the counter unit 1 is subtracted.

[0013]

In the case of a communication service that does not perform retransmission control, such as a voice signal or an image signal, the number of cells that have actually passed is counted by the counter unit 1 to obtain a billing-based parameter. In the case of a communication service that performs retransmission control, such as data, retransmission control is performed by cell discarding. Therefore, whether or not cell discarding has been performed is identified by the frame detection unit 3 and cell discarding is performed within the frame. If the cell does not occur, the number of cells in the frame is counted as the number of passing cells by the counter unit 1. If the cell is discarded,
Do not count the number of cells in that frame. Therefore, for a cell in a communication service that performs retransmission control of data and the like, the number of actually passed cells can be counted and used as a billing-based parameter.

When a cell of a communication service for performing retransmission control of data or the like is identified by the cell identification section 2, the segment type and sequence number of the cell are monitored. The frame detection unit 3 determines whether the cell is a cell including the head part of the frame in the information field, a cell including the intermediate part in the information field, or a cell including the last part in the information field according to the segment type. Since it can be identified, the number of cells is counted by identifying from the beginning to the end of the frame. That is, the number of cells in one frame can be counted. If the sequence number is cyclically repeated from 0 to 15 as described above, it can be determined that cell discard does not occur. If even one cell is missing, it is determined that cell discard has occurred. You can judge. When it is determined that cell discard does not occur in the frame as described above, the counted number of cells in the frame is added to the counter unit 1. If it is determined that the cell has been discarded, it is not added. Therefore,
The count content of the counter unit 1 indicates the number of valid passing cells.

When the passing cell is counted by the counter unit 1 and the cell of the communication service for performing the retransmission control of the data or the like is identified by the cell identifying unit 2, the frame detecting unit 3 performs the same operation as described above. It monitors the segment type and sequence number of the cell, identifies whether the cell is at the beginning or end of the frame, and counts the number of cells in the frame. The presence / absence of cell discard is identified based on the sequence number. If no cell discard occurs, the number of passing cells counted by the counter unit 1 is used as a metering parameter for charging. When a cell is discarded, the number of cells in the frame counted by the frame detector 3 is subtracted from the number of passing cells counted by the counter 1. Therefore, the count content of the counter unit 1 indicates the number of effective passing cells in which cell discard does not occur.

[0016]

FIG. 2 is a block diagram of a main part of an embodiment of the present invention, showing a main part of an accounting processing section in an ATM network, and omitting a buffer memory, a routing switch section and the like. In the figure, 11 is a counter unit, 12 is a cell identification unit, 13 is a frame detection unit, and 21 is a counter (CNT).
2) and 22 are +1 circuits, 23 is an addition circuit, 24 is a sequence number holding table, 25 is a subtraction circuit, 26 is a counter (CNT1) having a flag F, and 27 is a control operation unit.

The cell identification unit 12 identifies the types 1 to 3 of the passing cell, extracts the logical channel identifier VCI, the segment type ST and the sequence number SN, and outputs counters 21 and 26 and a sequence number holding table 24. , The segment type ST to the control operation unit 27, and the sequence number SN to the sequence number holding table 24. Type 4 is a protocol that supports a connectionless data communication service. This service is not provided by an exchange but is provided by a connection server. Since it is conceivable, this embodiment will be described except for the case of type 4.

The counters 21 and 26 and the sequence number holding table 24 have areas corresponding to the logical channel identifier VCI. The counter 26 has a count area and a 1-bit cell discard occurrence detection flag F corresponding to the logical channel identifier VCI. Having. Each time the logical channel identifier VCI is extracted, the counter 21 sets the logical channel identifier VC
+1 is added to the contents of the area corresponding to I by the +1 circuit 22. Therefore, the contents of the area corresponding to the logical channel identifier VCI of the counter 21 are the logical channel identifier VCI.
This indicates the number of corresponding passing cells.

The sequence number SN of the cell corresponding to the logical channel identifier VCI is written in the sequence number holding table 24, and the previous sequence number and the current sequence number are subtracted in the subtraction circuit 25. If cell discard does not occur, the sequence number is continuous in ascending order, and the subtraction output indicates 1. On the other hand, if the subtraction output is not 1, it is determined that cell discard has occurred. When the sequence number SN is cyclically given from 0 to 15 as described above, 0−15 ≠ 1, but if the difference is 1 or −15, it is determined that cell discard does not occur. be able to.

The control operation unit 27 determines whether or not cell discard has occurred based on the output signal of the subtraction circuit 25, and sets the flag F of the counter 26 when cell discard has occurred. When the segment type ST is BOM, it can be determined as the first cell of the frame, and when the segment type ST is EOM, it can be determined as the last cell of the frame. When the first cell of the frame is detected, the area corresponding to the logical channel identifier VCI is cleared, and when the last cell of the frame is detected, the contents of the area corresponding to the logical channel identifier VCI indicate the number of cells in the frame. If the flag F is not set at that time, it indicates that no cell discard occurs.

For cells of types 1 and 2 for which retransmission control of audio signals, image signals, and the like is not performed, the count content of the counter 21 of the counter unit 11 indicates the number of passing cells. It can be a parameter. However, for a type 3 cell for which retransmission control of data and the like is performed, it is necessary to consider a frame due to cell discard.

The cell discriminating section 12 discriminates the type 1 cell or the type 3 cell, and for the type 3 cell, the frame detecting section 13 discriminates the first cell and the last cell of the frame. , The number of cells in the frame is counted, and it is determined whether or not cell discarding has occurred. If cell discarding does not occur, the number of cells in the frame is regarded as the number of passing cells and the counter 21 of the counter unit 11 is determined. , And when the cell is discarded, the accumulation is not performed.

The number of passing cells is counted by the counter 21 of the counter section 11 for any of the types 1 to 3.
The frame detector 13 counts the number of cells passing through the frame. If no cell discard occurs, the counter 1
The count content of the counter 21 of 1 is defined as the number of passing cells of the type 3 cell, and when a cell is discarded, the number of passing cells in the frame counted by the frame detection unit 13 is calculated from the count content of the counter 21 of the counter unit 11. Can be subtracted.

FIG. 3 is a flowchart of an embodiment of the present invention, showing steps (a) to (l).
Is identified, the segment type S of the cell is identified.
It is determined whether T indicates BOM (head), EOM (final), SOM (single), or COM (intermediate) (a), B
In the case of OM (head), the area corresponding to the logical channel identifier VCI of the counter (CNT1) 26 is set to 1 as an initial value (b), and the flag F is set to "0" (c).

In the case of COM (intermediate), whether or not the sequence number SN is continuous is determined by the output signal of the subtraction circuit 25 (i). If the output signal of the subtraction circuit 25 is not 1 (N), Since the cell discard has occurred, the flag F of the counter 26 is set to "1" (1). When the output signal of the subtraction circuit 25 is 1 (Y), the cell discard does not occur, and it is determined whether the flag F has been set to "1" because the cell discard has already occurred. It is determined (j) that if "1" (Y) is a frame in which cell discard has already occurred, it is left as it is, and if not "1" (N), it is a frame in which no cell discard has occurred Therefore, the content of the area corresponding to the logical channel identifier VCI of the counter (CNT1) 26 is incremented by 1 (k).

In the case of SOM (single), since it is a single cell of type 3, the contents of the area corresponding to the logical channel identifier VCI of the counter (CNT2) 21 are stored in the same manner as the cells of type 1 and 2. +1 is added (h). In the case of EOM (final), it is determined whether or not the sequence number SN is normal (d). If the output signal of the subtraction circuit 25 is not 1 and abnormal (N), it is left as it is. If the signal is normal (Y), it is determined whether or not the flag F is "0" (e). If the signal is not "0" (N), the flag F is left as it is. Since the discard has not occurred, the content of the area corresponding to the logical channel identifier VCI of the counter (CNT1) 26 is incremented by 1 (f), and the area corresponding to the logical channel identifier VCI of the counter (CNT2) 21 of the counter unit 11 is incremented. The content of the counter (CNT1) 26, which indicates the number of cells in the frame, is added to the content of (1) by the adding circuit 23 and set.

That is, for a type 3 cell for which retransmission control is to be performed, the frame detection unit 13 identifies the beginning and end of the frame by the segment type ST,
The number of cells in the frame is counted by the counter 26, and whether or not the cell is discarded is identified based on the sequence number SN. If the cell is discarded, the flag F of the counter 26 is set, and the end of the frame is set. When the cell is identified, if the flag F of the counter 26 is not set, it is determined that the frame does not cause cell discard, and the number of cells in the frame counted by the counter 26 is accumulated in the counter 21 of the counter unit 11. Calculate. When the flag F is set and it is determined that the frame has caused the cell discard, the counter 21 does not accumulate.
Therefore, since only the number of valid cells is counted by the counter 21, the content of the count can be used as a metering parameter for charging.

In the above-described embodiment, the number of cells in a frame is counted by the counter 26 of the frame detecting section 13 and, when no cell discarding occurs, it is accumulated in the counter 21 of the counter section 11 via the adding circuit 23. Although the case is shown, the addition circuit 23 of the counter unit 11 is a subtraction circuit, and the counter 21 uses the type 1, 2
In the case of type 3 cells, the presence or absence of cell discarding is detected based on the sequence number SN, the number of passing cells in the frame is counted by the counter 26, and the presence or absence of cell discarding is determined by the flag F. Is displayed. In the above embodiment, step (j) of FIG.
As shown in (1), after the flag F is set to "1", the number of cells passing through the frame is not counted up. However, in this embodiment, the flag F is set to "1". After "", the number of passing cells in the frame is counted up.

When the last cell of the frame is identified and the flag F is not set, indicating that no cell discard has occurred, the count of the counter 21 is set to the number of valid cells, and If F is set to indicate that cell discard has occurred, the counter 2
The number of cells having the count of 6 is subtracted from the number of cells having the count of the counter 21. That is, for a frame in which a cell has been discarded, a cell that has already passed becomes invalid. Therefore, by subtracting the number of passing cells of the frame from the number of passing cells, the logical channel identifier VCI of the counter 21 at the end of the call is determined. Since the content of the corresponding area indicates the number of valid cells, it can be used as a pay-as-you-go parameter.

[0030]

As described above, according to the present invention, the number of passing cells is counted by the counter unit 1 for a cell for which retransmission control is not performed, and for a cell for which retransmission control is performed,
Since the number of cells in a frame in which cell discard does not occur is counted as the number of passing cells, the number of valid cells can be used as a metering parameter for charging. Also, the presence or absence of cell discard can be easily identified by the sequence number SN, and the start cell or the last cell of the frame can be easily identified by the segment type ST. Also in this case, the count content of the counter unit 1 indicates the number of valid cells.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of the present invention.

FIG. 2 is a main block diagram of an embodiment of the present invention.

FIG. 3 is a flowchart of an embodiment of the present invention.

FIG. 4 is an explanatory diagram of a cell.

FIG. 5 is an explanatory diagram of a cell format.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Counter part 2 Cell identification part 3 Frame detection part

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroshi Tomonaga 1015 Uedanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside Fujitsu Co., Ltd. 56) References JP-A-55-143872 (JP, A) JP-A-58-175388 (JP, A) JP-A-2-142245 (JP, A) JP-A-5-30132 (JP, A) Hei 4-45633 (JP, A) JP-B 63-59624 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04L 12/56 H04L 12/28 H04L 12/14 H04M 15 / 00

Claims (3)

(57) [Claims] In an ATM network for transmitting and receiving voice signals, image signals, data, and the like as cells of a fixed length, a counter (1) for counting the number of cells, and a cell identification unit (2) for identifying the type of cells. ) And a frame detection unit (3) for detecting a data frame, wherein the cell identification unit (2) identifies a cell of a communication service that does not perform retransmission control between transmission and reception such as the voice signal and the image signal. Then, the passing cell of the communication service is counted by the counter unit (1) and used as a usage-based parameter for charging for the communication service. The cell identification unit (2) controls retransmission between transmission and reception such as the data. When the cell of the communication service to be performed is identified,
The frame in the communication service is detected by the frame detection unit (3), and the counting of the number of cells in the counter unit (1) is performed only for a frame in which no cell is discarded. A media-based charging control method, wherein the content of the count is used as an amount-based parameter for charging the communication service. 2. When the cell identification unit (2) identifies a cell of a communication service that performs retransmission control between transmission and reception such as the data, monitors the segment type and sequence number of the cell and detects the frame. In the section (3), the number of cells from the cell including the head portion of the frame in the information field to the cell including the end portion of the frame in the information field is counted. The media-based charging control method according to claim 1, wherein the number of cells is added to the counter unit (1). 3. When the passing cell is counted by the counter unit (1) and a cell of a communication service for performing retransmission control between transmission and reception such as the data is identified by the cell identification unit (2), the cell of the cell is identified. The segment type and the sequence number are monitored, and the frame detector (3) counts the number of cells from the cell including the head of the frame in the information field to the cell including the end of the frame in the information field. 2. The media-based charging control method according to claim 1, wherein the count of the number of cells is subtracted from the count of the counter unit (1) when an abnormality of the sequence number due to cell discard is detected.