JP2002368799A - Band controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a band controller that decides a cell transmission time according to a maximum band and a minimum band of a band control group. SOLUTION: The band controller of this invention decides a transmission time for an arrived cell among transmission times assigned to a band control group to which a connection of the arrived cell belongs and is provided with a reservation time cunt means that calculates a transmission reservation time for a maximum band of the band control group of the cell on the basis of the preceding transmission time and the maximum band parameter or calculates a transmission reservation time for a minimum band of the band control group for the cell on the basis of the preceding transmission time and the minimum band parameter and also with a transmission destination discrimination means that discriminates whether the cell storage address is to be transmitted or the cell is moved to another queue depending on a queue of each band control group storing a cell storage memory address.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a band control device. For example, ATM (AsynchronousTransf
er Mode), which can be applied to a bandwidth control device in which a plurality of bandwidth control methods are interposed in different connections, and is particularly suitable when transmission requests for cells in the same bandwidth control group compete.

[0002]

2. Description of the Related Art In recent years, in the field of information communication, diversification of communication needs, advancement of information exchange / transmission technology, development of device technology, and the like have resulted in high-speed and wide-band exchange and transmission of user information at high speed. The practical use of a service integrated digital network (hereinafter, B-ISDN) is rapidly progressing.

In this B-ISDN, ATM is adopted as an information transfer system. In this ATM communication, information is transferred in fixed-length packets called cells.
Be exchanged. In this case, the transfer destination of the cell is identified based on destination address information assigned to each cell.

[0004] Therefore, unlike the conventional time-division circuit switching, each terminal can transmit a cell to an arbitrary position of a slot on a vacant time axis, and can transmit a cell to an arbitrary position on a transmission line in a network. Cell multiplexing becomes possible.

For this reason, in the ATM communication, a cell communication band (for example, a peak cell rate or an average cell rate) to be used is reported to each terminal before the start of communication, and band management is performed on the network side based on the information.

The cell communication band has a hierarchical structure, and the cell communication band is provided with a prescribed value. For example, a logical path is composed of a plurality of logical channels, and some logical channels form one group (class) by cell identification or the like. The maximum bandwidth (shaping) that can be used for a logical path is defined, and the maximum bandwidth and the minimum bandwidth are also defined for each group (class) of the logical path.

[0007] The network side manages the bandwidth of the above-structured cell communication band based on cell information.
One of the intra-network management functions is band control.

Conventionally, in a bandwidth control apparatus corresponding to the above hierarchical structure, the priority of cell transmission is set in advance for each logical path and for each group (class), and cell transmission is performed as follows. ing.

FIG. 2 shows the overall configuration of a conventional band control device. The conventional band control device has a cell storage unit 1 and a transmission time control unit 2.

The cell storage means 1 has an internal structure as shown in FIG. 4, and has a function of storing cells for each class (group) when the cell communication band is exceeded.

The transmission time control means 2 has an internal structure as shown in FIG. 3 and has a function of making a transmission request to the cell storage means 1. Specifically, the shaping for each logical path is performed. It has a function of controlling the rate and the rate for each class, and a function of selecting one cell in response to a transmission request for a plurality of class cells (transmission buffer number notification).

Each time a cell is transmitted / received, the cell storage means 1 provides the transmission time control means 2 with the buffer status of the cell storage means 1.

When the cell storage means 1 receives a cell,
The cell data is stored in the empty memory based on the cell header (cell information) of the cell, and the stored cell storage address is written to the buffer in the buffer-by-buffer address management queue. The written buffer number is given to the transmission time control means 2 as a reception buffer number notification.

When transmitting a cell, the cell storage means 1 requests the transmission time control means 2 for a transmission buffer number.

The transmission time control means 2 receiving the transmission buffer number request controls the maximum bandwidth (shaping) of the logical path by the shaping rate control section 3 incorporated therein.
The bandwidth for each class (group) is controlled by the built-in class-specific rate control unit 4, and a transmission request is transmitted as a transmission buffer number notification at every predetermined cycle.
Has given to.

When making a transmission request to a plurality of classes, the output cell selection control unit 5 considers one of the preset priorities among the classes and whether or not there is a cell in the queue. A transmission request in the logical path has been selected.
When requesting transmission to a plurality of logical paths, the contention control unit 7 selects a transmission request based on a preset priority or the like.

The cell transmission operation of the conventional band controller having such a configuration will be described with reference to FIG.

The transmission period of the transmission request by the bandwidth control unit for each logical path included in the transmission time control means 2 is such that "shaping unit number 0" is once every three cell times and "shaping unit number 1" is four. Once per cell time. here,
The “shaping unit number x” is a number x that identifies the maximum bandwidth for each logical path of the cell. The cell time represents a unit time of cell transmission.

The period at which the class-specific rate control section 4 sends out a transmission request is such that the classes 0, 1 and 2 belonging to the "shaping unit number 0" are each transmitted with respect to the "shaping unit number 0" transmission request. 1 cell out of 2 times,
One cell out of three times, one cell out of three times. Class 0, class 1, and class 2 belonging to “shaping unit number 1” are also one cell out of two times, one cell out of three times, and one cell out of three times in response to the transmission request of “shaping unit number 0”. It is. That is, a transmission request is transmitted from a cell of each class in a cycle set for each logical path (shaping unit).

When transmission requests conflict between classes, the priorities are transmitted in the order of class 0, class 1, and class 2, and between logical paths, "shaping unit number 0", "shaping unit number 1", "Shaping unit number 2"
Round robin control that gives an opportunity to send repeatedly in this order.

In FIG. 5, the set transmission time control means 2 receives a transmission request of "shaping unit number 0" at the time of the first cell time. In this case, since transmission requests are competing between class 0 and class 2 of “shaping unit number 0”, transmission requests for class 0 are transmitted in accordance with the above priority.

The fourth cell time is the second transmission cycle of "shaping unit number 0". Since there is no transmission request for any class, the transmission time of class 1 for which the previous transmission request could not be transmitted is determined. A transmission request is sent. That is, class 1 which is given priority next to class 0 is transmitted.

Similarly, when there is a conflict between logical paths, a transmission request is sent to the cell storage means 1 according to the above-described priority.

As described above, in the conventional band control device, the transmission time control means 2 transmits the transmission request for each class to the cell storage means 1 in the transmission cycle of the logical path transmission request. Reads the cell from the corresponding memory based on the transmission request and transmits the cell.

[0025]

However, the conventional band control device has the following two problems.

One is that the transmission time control means 2 transmits transmission requests in accordance with the priority order between logical paths or between classes, so that transmission requests of non-priority (low priority) classes are delayed. There is a possibility that cells cannot be transmitted according to the maximum bandwidth and the minimum bandwidth of each class.

That is, since the priority is determined for each class, the maximum bandwidth is always guaranteed for class 0, but non-priority (low priority) for class 1 and below.
Therefore, there is a possibility that the minimum bandwidth is not guaranteed.

For example, as shown in FIG. 5, the number of transmission requests of each class during the 23rd cell time is: Class 0 of shaping unit number 0 = 4 cells Class 1 of shaping unit number 0 = 3 cells Shaping unit number 0 class 2 = 1 cell Class 0 of shaping unit number 1 = 3 cells Class 1 of shaping unit number 1 = 2 cells Class 2 = 0 cell of shaping unit number 1

The class 2 of "shaping unit number 0" has a low priority between the classes, but is likely to protect a band of 1/6 of the lowest band. However, if the transmission request between the other classes matches, Since the priority is lower than class 0 and class 1, the transmission interval of class 2 varies, and there is a possibility that the minimum bandwidth cannot be guaranteed.

Further, in class 2 of "shaping unit number 1", the timing of a cell transmission request is occupied more than in class 0 and class 1. Therefore, it is necessary to transmit all of the above cells during the above 23 cell time. Is not completed and does not meet the minimum bandwidth.

The second problem is that the bandwidth control method generally differs depending on the system, and the conventional bandwidth control method as described above cannot be applied to the bandwidth control of another system. .

For example, when performing band control for each logical channel before performing band control for each class, or performing band control for each logical path after performing band control for each logical channel, generally, Since the number of channels is larger than the number of classes of logical channels, the bandwidth control may be duplicated and the processing may be performed, resulting in unnecessary bandwidth control.

Therefore, in a cell communication band having a plurality of connections of arriving cells in a hierarchical structure, a band control device capable of transmitting a plurality of transmission cells requested to transmit while maintaining the minimum band and the maximum band of the connection is provided. It has been demanded.

Further, there is a need for a versatile band control device which can be applied to a case where the system is combined with another system having a different band control system.

[0035]

In order to solve such a problem, the bandwidth control device of the present invention assigns each connection to one of the bandwidth control groups, and sets the transmission time for each bandwidth control group. A band that is fixedly determined according to a control band defined in each band control group, and determines a transmission time for an arriving cell among transmission times allocated to the band control group to which the connection of the cell belongs. A control device, which comprises a cell storage means and a transmission time control means, wherein the transmission time control means stores a maximum bandwidth parameter of a bandwidth control group to which the arriving cell belongs. Storage means, and minimum bandwidth parameter storage means for storing the minimum bandwidth parameter of the bandwidth control group to which the arrival cell belongs A previous transmission time storage means for storing the transmission time of the previous cell; and calculating the transmission reservation time in the maximum bandwidth of the bandwidth control group of the cell based on the previous transmission time and the maximum bandwidth parameter, or Based on the transmission time and the minimum bandwidth parameter, a reservation time calculation means for calculating a transmission reservation time in the lowest bandwidth of the bandwidth control group of the cell, and a transmission reservation time calculated by the reservation time calculation means, A transmission reservation queuing means for queuing at each transmission reservation time and instructing transmission of the cell at the transmission reservation time.

The cell storage means stores the cell data of the arriving cell in a free memory, and an address for queuing the memory address of the storage means for each band control group based on the cell information of the cell. A queuing unit, and a destination determining unit that determines whether to transmit the cell or transfer a memory address to another queue of the address queuing unit according to a queue for each band control group of the address queuing unit. Means.

[0037]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (A) First Embodiment An application of a first embodiment of a band control device according to the present invention will be described below with reference to FIGS. 1, 2 and 6. FIG.

In the first embodiment, in a logical path having a class having a predetermined band as a hierarchical structure, a transmission request (notification of a transmission buffer number) is transmitted according to the maximum band and the minimum band of the class to which the arrival cell belongs. The transmission time control means for sending to the server will be described.

The overall configuration of the bandwidth control device according to the first embodiment is as shown in FIG.

(A-1) Configuration of the First Embodiment FIG. 1 is a block diagram showing the internal configuration of the transmission time control means according to the first embodiment.

As shown in FIG. 1, the transmission time control device 1
Is the reference time generation unit 12, the non-priority transmission reservation queue 17
b, priority transmission reservation queue 17a, non-priority read time unit 19, priority read time unit 18, reservation time calculation unit 13,
Last transmission time storage unit 16, maximum band cell interval storage unit 1
4. It has a minimum band cell interval storage unit 15.

The reference time generator 12 counts the time of one cycle from 0 to m regardless of the presence or absence of a cell transmission request. The reference time generation unit 12 gives the generated reference time to the priority read time unit 18, the non-priority read time unit 19, and the reserved time calculation unit 13.
After counting the last m−1 of one cycle, the reference time generation unit 12 returns to 0 again and counts 0, 1, 2,.

Here, m has a correspondence with the number of transmission reservation queues described later, and is a value large enough to reserve a transmission time. That is, since the period of the reference signal only needs to have a correspondence with the number of transmission reservation queues, for example, m may be an integer multiple of the number of transmission reservation queues.

The maximum band cell interval storage unit 14 has a function of storing a maximum band cell transmission interval Tmax which is a maximum band parameter set in advance for each buffer number of the cell storage means 1. Maximum band cell interval storage unit 14
Is used to set the maximum band cell transmission interval Tmax in accordance with the buffer number (for each class of arrival cell) of the reception buffer number notification input to the reservation time calculation unit 13, and the maximum set for each buffer is set. The band cell transmission interval Tmax is provided to the reservation time calculation unit 13. Here, in the present embodiment, the buffer number of the cell storage means 1 is for each class. Accordingly, the maximum band cell interval storage unit 14 stores the maximum band cell interval for each class.

The minimum band cell interval storage unit 15 is the same as the maximum band cell interval storage unit 14, and stores a minimum band cell transmission interval Tmin preset for each buffer.

In general, a class to which an arriving cell belongs is identified, and the identified class declares one band, so that a transmission request in that band is sent out. The transmission request is transmitted by declaring a plurality of communication bands including the band and the minimum band.
Therefore, the maximum bandwidth parameter and the minimum bandwidth parameter may be parameters that can set the maximum bandwidth and the minimum bandwidth for each class.

The previous transmission time storage section 16 has a function of storing the transmission time of the previously transmitted transmission request. The previous transmission time storage unit 16 gives the stored transmission time of the previous transmission request to the reservation time calculation unit 13.

The reservation time calculation unit 13 has a function of calculating the transmission time of the transmission request from the time when the cell storage unit 1 is notified of the reception buffer number. Reservation time calculator 1
Reference numeral 3 designates transmission reservation of a transmission request based on the transmission time calculated as a result.

In this embodiment, the method of calculating the transmission time is as follows.
From buffer number notification to each buffer number (for each class)
Is read from the maximum band cell transmission interval Tmax or the minimum band cell transmission interval Tmin, and the transmission time is calculated from the maximum band cell transmission interval Tmax or the minimum band cell transmission interval Tmin.

That is, the current time T and (the previous transmission time Tl
The current transmission request time is calculated by comparing the time with (+ maximum band cell transmission interval Tmax) or by comparing the current time T with (previous transmission time Tl + lowest band cell transmission interval Tmin). .

When the current time T is equal to or less than (previous transmission time Tl + maximum band cell transmission interval Tmax), the transmission cell satisfies the maximum band. Tmax) is reserved in the non-priority transmission reservation queue 17b as the reservation time Tr of the transmission request of the cell.

The current time T is set to (previous transmission time Tl
If it is larger than (+ maximum band cell transmission interval Tmax), the transmission cell cannot satisfy the maximum band, and the current time T is compared with (previous transmission time Tl + lowest band cell transmission interval Tmin). When the current time T is less than or equal to (previous transmission time Tl + minimum band cell transmission interval Tmin), it means that the transmission cell satisfies the minimum band. Tmin) is set to the reservation time Tr of the transmission request.
Is reserved in the non-priority transmission reservation queue 17b.

The current time T is set to (the previous transmission time Tl
If it is larger than (+ the minimum band cell transmission interval Tmin), the transmission cell cannot satisfy the minimum band, and the current time T is reserved in the priority transmission reservation queue 17a as the reservation time Tr of the transmission cell. .

The transmission reservation queue 17 stores the reservation time calculation unit 1
3 is provided with a function of temporarily storing the transmission request whose transmission time has been determined. Transmission reservation queue 17
The transmission request is read at the transmission time by the read time units 18 and 19, and is notified to the cell storage unit 1 as a transmission buffer number notification.

The transmission reservation queue 17 is roughly divided into a priority transmission reservation queue 17a and a non-priority reservation queue 17b. As described above, the transmission buffer number to which the transmission request should be transmitted with priority is written in the priority transmission reservation queue 17a. In addition, the non-priority transmission reservation queue 17b
As described above, the transmission buffer number whose current time T is earlier than the transmission request time is written in the transmission buffer number.

Each of the priority transmission reservation queue 17a and the non-priority reservation queue 17b has m queues, and has a queue structure corresponding to reference times from 0 to m-1. That is, the number of queues corresponding to the reference time is provided, and it is only necessary to be able to distinguish between priority and non-priority.
Therefore, the circuit configuration is not limited to the circuit configuration of the present embodiment. For example, the circuit configuration may be separately provided for each transmission time.

The read time sections 18 and 19 send the transmission reservation queue 17 based on the value specifying the queue storing the buffer number and the reference time from the reference time generation section 12.
Has a function of reading the transmission buffer number stored in the storage buffer.

The read time sections 18 and 19 have a priority read time section 18 and a non-priority read time section 19, and correspond to and correspond to the priority transmission reservation queue 17a and the non-priority transmission reservation queue 17b, respectively. It is checked whether or not the buffer numbers are stored in each of the transmission reservation queues 17a and 17b. When the stored buffer numbers are checked, a value specifying the queue is held. The read time is advanced until a queue containing a buffer number is found.

When the reference time becomes equal to the value specifying the queue, the read time units 18 and 19 holding the value specifying the queue read the buffer numbers stored in the corresponding queue. The buffer number is sent to the cell storage means 1 as a transmission request.

When buffer numbers are stored in both the priority transmission reservation queue 17a and the non-priority transmission reservation queue 17b, the buffer numbers stored in the priority transmission reservation queue 17a are read out with priority, and the buffer numbers are read out. Send the number as a transmission request.

(A-2) Operation of First Embodiment The operation of the band control device according to the present embodiment will be described below with reference to FIG.

When a cell arrives at the cell storage means 1, cell data is stored in an empty cell storage memory of the cell storage means 1, and a cell storage address is temporarily stored for each class based on the cell header of the cell. You. The buffer number storing the cell storage address is notified to the transmission time control means 2 as a reception buffer number.

When a cell is transmitted from the cell storage means 1, a transmission buffer number is requested from the transmission time control means 2;
The notified transmission buffer number request is sent to the reservation time calculation unit 1
3, the transmission reservation queue 1 based on the buffer number.
It is confirmed whether or not the corresponding buffer number exists in 7 (step 21). That is, it is checked to avoid duplicate transmission requests. If the buffer number is not in the transmission reservation queue, a reservation is made by the reservation time calculation unit 13 (steps 22 to 27). That is, the transmission request transmission time of the cell is calculated.

For example, let the time when the notified buffer number arrives at the reservation time calculation unit 13 be the current reference time T, the current reference time T and the previous transmission time Tl
(N) + the maximum band cell interval Tmax (n) is compared (step 22).

Here, n indicates the buffer number in which the memory address is stored.

If T ≦ Tl (n) + Tmax (n), it is determined that the maximum bandwidth is satisfied, and Tl (n)
+ Tmax (n) is set as a new Tl (n), and the new Tl (n) is set as a reservation time Tr (step 26).
A buffer number is reserved in the Tr-th queue of the non-priority transmission reservation queue 17b (step 25).

If T> Tl (n) + Tmax (n), it is determined that the maximum band is not satisfied, and the current reference time T is the previous transmission time Tl (n) + the cell for the lowest band. Is compared with the interval Tmin (n) (step 2
3). If T ≦ Tl (n) + Tmin (n), the minimum bandwidth is satisfied, so Tl (n) + Tmin (n) is set as a new Tl (n), and this new Tl (n) is set as the reservation time. The buffer number is reserved in the Tr-th queue of the non-priority transmission reservation queue 17b (Step 25).

Further, T> Tl (n) + Tmin (n)
If so, it is determined that the maximum bandwidth and the minimum bandwidth are not satisfied, the current reference time T is set as a new Tl (n), and the new Tl (n) is set as a reservation time Tr (step 24). ), A buffer number is entered in the Tr-th queue of the priority transmission reservation queue 17a (step 25).

The buffer number for which the transmission request transmission time is calculated as described above is given to the determined transmission reservation queue 17, and the reading time units 18 and 19 read the buffer number.

The operation of reading the buffer number from the transmission reservation queue 17 and transmitting the transmission request at this time will be described below.

The priority reading time section 18 and the non-priority reading time section 19 confirm whether or not the buffer numbers stored in the transmission reservation queue 17 are in the corresponding transmission reservation queue 17. The transmission reservation queue 17 in which the buffer number is found provides a value specifying the queue to the read time units 18 and 19, and the value specifying the given queue is held in the read time units 18 and 19. When the held queue specific value matches the reference time, the read time units 18 and 19 read the buffer number of the transmission reservation queue 17 and send it as a transmission request. Further, the reading time units 18 and 19 advance until a queue containing a buffer number is found.

After reading the cell from the cell storage means 1,
If another cell exists in the same buffer number, the next transmission reservation is made in the same manner as when the cell arrives.

(A-3) Effects of the First Embodiment As described above, the transmission time control means provided in the band control device of the first embodiment includes a parameter for the maximum band cell interval and the minimum band cell interval. By providing a reservation time calculation unit that calculates the transmission reservation of the transmission request by using, the minimum bandwidth is guaranteed by reserving the cell transmission request transmission time, and it is possible to transmit cells up to the maximum bandwidth. Become.

(B) Second Embodiment Next, the application of the band controller according to the second embodiment of the present invention will be described in detail with reference to FIG.

(B-1) Configuration of the Second Embodiment FIG. 7 is a block diagram showing the overall configuration of the cell storage means provided in the band control device of the second embodiment.

As shown in FIG. 7, the cell storage means 1 includes a cell distribution unit 28, an empty memory address storage queue 29,
It has an address management queue 30 for each buffer, a cell storage memory unit 31, and a destination determination unit 32.

The difference from the cell storage means provided in the conventional band control device is that a transmission destination determination unit 32 is provided. That is,
Bandwidth control is performed by the cell storage means determining whether to transmit a cell or queue the cell storage address in another queue again according to the queue of the cell storage address queued for each class. . here,
Only the transmission destination determining unit 32 will be described.

The destination judging section 32 has a preset destination searching function. Destination determination unit 32
Receives a transmission request from the transmission time control means, is given a cell storage address read out from the buffer-based address management queue 30, searches for a preset destination, and transmits a cell or transfers a cell storage address. This is to determine whether or not to do so.

In the present embodiment, the transmission destination determining unit 32 determines whether to transmit a cell or transfer a cell storage address. The correspondence is determined by the destination search correspondence table 33 set in advance.

The transmission destination search address 33 shown in FIG. 7 is one in which cell transmission or cell storage address transfer is set for each buffer classified into each class.

For example, when the cell storage address of the cell requested to be transmitted is queued in the buffer number “1”, the transmission destination determination unit 32 determines the cell storage address by the transmission destination search table 33 as the buffer number “1”. Is queued in the buffer of buffer number "6". That is, the cell storage address is queued in another buffer in the per-buffer address management queue 30 according to the transmission destination search table 33 set in advance.

The cell storage address stored in the buffer number “6” is queued in the buffer of the buffer number “8” from the buffer number “6”.

The cell storage address queued at buffer number "8" is read out of the cell storage memory and transmitted to the outside. At this time, the cell storage address where the transmitted cell was present is returned to the free memory address storage queue 29 as a free address.

(B-2) Operation of the Second Embodiment The operation of the cell storage means provided in the band control device according to the present embodiment will be described below.

The cell received by the band controller acquires a vacant memory address from the vacant memory address storage queue 29 and is stored in a vacant address.

In the cell distribution unit 28, based on the cell header of the cell, a buffer in which the cell storage address is classified for each class is identified, and the cell storage address is written to the buffer of the identified buffer-based address management queue 30. It is.

The cell storage address written in the per-buffer address management queue 30 is notified to the transmission time control means 2 as a reception buffer number.

When transmitting a cell, a transmission buffer number request is given to the transmission time control means 2, and a transmission buffer number based on the transmission buffer number request is given from the transmission time control means 2.

The transmission time control means 2 selects a cell to be transmitted, and a transmission buffer number is given to the cell storage means 1.

Based on the given transmission buffer number,
The cell storage address is read from the buffer-based address management queue 30 and provided to the transmission destination determination unit 32.

The destination determining unit 32 specifies from which buffer number in the buffer-based address management queue 30 this cell storage address has been read, and sends the cell to the outside by a preset destination search table 33. It is determined whether to transmit or be queued in another buffer.

When transmitting an external cell, the cell storage address is returned to the empty memory address storage queue 29, and
The cell storage unit 1 stops the request for the transmission buffer number to the transmission time control unit 2 until a cell is transmitted.

When the data has been written to another buffer-based address management queue 30, the transmission time control means 2 is notified of the reception buffer number, and the transmission time control means 2
The cell transmission is repeated according to the transmission buffer number request from.

(B-3) Effects of the Second Embodiment As described above, according to the cell storage means of the band control device of the present embodiment, the provision of the transmission destination determining unit allows the queued cell storage addresses to be buffered. Each cell can be read from the address management queue and transmitted according to the class band in which the cell is transmitted, or the cell storage address can be rewritten in another buffer, so that the cell is transmitted to a desired transmission band. be able to.

Therefore, band control can be performed for other systems having different band control.

(C) Other Embodiments The present invention can be applied to the band control device provided with both the transmission time control means or the cell storage means described in the first and second embodiments.

The transmission time control means of the first embodiment and the second
The bandwidth control device provided with the cell storage unit of the embodiment can transmit the transmission request to the cell storage unit in a shorter time, and the transmission time control unit can transmit the transmission request to the cell of the lower priority class. In the requested cell storage means, the transmission band can be adjusted.

In the first and second embodiments, the cell storage address is queued by a buffer divided for each class. For example, the cell storage address is queued by a buffer divided for each logical path or logical channel. In this case, for example, the transmission destination search table may be set corresponding to a logical path or a logical channel.

Further, in the first embodiment, the cell interval for the maximum band and the cell interval for the minimum band are set for each class, but any communication band that can keep the maximum band and the minimum band may be used. For example, it is possible to subdivide the band control by providing a band parameter in which a plurality of bands can be set between the maximum band and the minimum band. Further, the cell interval for the maximum band and the cell interval for the minimum band are set for each buffer in which the address of the transmission cell is stored, but the present invention is not limited to each buffer (for each class), but may be for each group. For example, the present invention can be applied to a group including a plurality of logical paths.

Further, in the first embodiment, the transmission reservation queue 17 stores the transmission requests by classifying the transmission reservation queue 17 into the priority transmission reservation queue 17a and the non-transmission reservation queue 17b. However, for example, three or more priorities such as “high priority”, “medium priority”, and “low priority” may be used.

Further, the transmission destination determining unit described in the second embodiment reads out cell data by re-accumulating the cell storage address in another buffer in the buffer-by-buffer address management queue according to the transmission destination search table. However, the setting of the destination search table is not limited to this embodiment,
For example, the transfer count of the cell storage address may be set so that re-accumulation can be performed three times or more at maximum. Although the transmission destination search table described in the second embodiment corresponds to a buffer for each class, a correspondence table corresponding to a logical path or a logical channel may be set.

[0102]

As described above, according to the present invention, the transmission time control means of the band control device can transmit a transmission request in the lowest band using the parameters of the cell interval for the maximum band and the cell interval for the minimum band. By providing the reservation time calculation unit that calculates the reservation time, it is possible to reserve the transmission reservation time that guarantees the minimum band for the cell transmission request, and prevent cell transmission over the maximum band.

Also, in the cell storage means provided in the band control device, there is provided a means for judging the destination read out of the address read from the buffer-based address management queue and rewriting the address into another buffer-based address management queue.
Buffer usage is not fixed, setting can be changed for each desired control, it can be used for systems with different transmission bands, and versatile bandwidth control is provided It is possible to do.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an overall configuration of a transmission time control unit according to a first embodiment.

FIG. 2 is a block diagram showing an overall configuration of a conventional band control device.

FIG. 3 is a block diagram showing an entire configuration of a conventional transmission time control means.

FIG. 4 is a block diagram showing an overall configuration of a conventional cell storage means.

FIG. 5 is a diagram showing an operation of transmission time control by a conventional band control device.

FIG. 6 is a flowchart illustrating an operation of a transmission time control unit included in the band control device according to the first embodiment.

FIG. 7 is a block diagram illustrating an overall configuration of a cell storage unit included in a band control device according to a second embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Cell storage means, 2 ... Transmission time control means, 3 ... Shaping rate control part, 4 ... Class rate control part, 5 ...
Output cell selection control unit, 6 setting parameter unit, 7 conflict control unit, 8, 28 cell distribution unit, 9, 29 free memory address storage queue, 10, 30 buffer-based address management queue, 11, 31 ... Cell storage memory, 12: reference time generation unit, 13: reserved time calculation unit, 14: maximum band cell interval storage unit, 15: minimum band cell interval storage unit,
16: Previous transmission time storage unit, 17a: Priority transmission reservation queue, 17b: Non-priority transmission reservation queue, 18: Priority read time unit, 19: Non-priority read time unit, 32: Destination determination unit, 33: Destination search table.

Claims (4)

[Claims] 1. Each connection belongs to one of the bandwidth control groups, the transmission time for each of the bandwidth control groups is fixedly determined according to the control bandwidth specified in each of the bandwidth control groups, The transmission time control means is a band control device that determines a transmission time among transmission times assigned to the band control group to which the connection of the cell belongs, and the transmission time control means Maximum bandwidth parameter storage means for storing the maximum bandwidth parameter of the bandwidth control group to which the cell belongs, minimum bandwidth parameter storage means for storing the minimum bandwidth parameter of the bandwidth control group to which the arriving cell belongs, and storing the transmission time of the previous cell Last transmission time storage means, based on the last transmission time and the maximum bandwidth parameter, A reservation for calculating a transmission reservation time in the maximum bandwidth of the bandwidth control group of the cell or calculating a transmission reservation time in the minimum bandwidth of the bandwidth control group of the cell based on the previous transmission time and the minimum bandwidth parameter. Time calculation means, and transmission reservation queuing means for queuing the transmission reservation time calculated by the reservation time calculation means for each transmission reservation time and instructing transmission of the cell at the transmission reservation time. A band control device characterized by the above-mentioned. 2. The transmission reservation queuing unit instructs transmission of the cell according to a transmission priority based on the transmission reservation time calculated by the reservation time calculation unit. Bandwidth control device. 3. Each connection belongs to one of the band control groups, and the transmission time for each band control group is fixedly determined according to the control band specified for each band control group, A band control device that stores the cell storage means and determines the transmission time among the transmission times assigned to the band control group to which the connection of the cell belongs, wherein the cell storage means Storage means for storing the cell data of the selected cell in a free memory, and address queuing means for queuing the memory address of the storage means for each band control group based on the cell information of the cell; The cell is transmitted or the memory address is transmitted according to the queue of the memory address. And a transmission destination determining unit for determining whether to transfer the data to another queue of the address queuing unit. 4. Each connection belongs to one of the bandwidth control groups, the transmission time for each bandwidth control group is fixedly determined according to the control bandwidth defined in each bandwidth control group, for,
3. A transmission time control unit according to claim 1, wherein the transmission time is determined from transmission times allocated to a bandwidth control group to which the connection of the cell belongs. And a means for controlling the bandwidth.