JP2002237842A - Communication network system and line concentrating node device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent inequality from occurring among the bands of UBR connections depending on the location of a line concentrating node device. SOLUTION: In a communication network system, a plurality of line concentrating node devices are connected like a ring through an ATM line, and the devices multiplex a plurality of connections having a different required quality to output them to an upstream line concentrating node device. In the device distributes, inputted calls are distributed to a CBR connection/UBR connection distributing section 101, and the UBR connection is accumulated in a cell buffer 102 for CBR connection. Further, the UBR connection is distributed for each device in a signal sending node distributing section 103, is accumulated for each device, and is read with an equal round robin reading control section 106 successively. The CBR connection is read with a CBR connection preferential reading control section 106, and the UBR connection read in the section 105 is outputted to the upstream line concentration node device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication network system and a concentrator node device using an ATM, and more particularly, to a method for fairly using a communication band of a URB call transferred to an ATM trunk between the concentrator node devices. The present invention relates to a communication network system and a concentrator node device.

[0002]

2. Description of the Related Art Generally, ATMs (Asynchronous Transfe
r Mode: In a network using an asynchronous transfer mode (CRT) line, a CBR call (Constant B
By multiplexing an It Rate Conection and a URB call (Unassingned Bit Rate Conection) that does not necessarily guarantee a communication band, a multiple communication service is enabled without impairing the line use efficiency.

Here, the total bandwidth of the entire URB call, that is, the total bandwidth of the CBR call from the maximum communication speed of the ATM line, that is, the bandwidth excluding the CBR band is fixedly allocated to the URB band. In general, a URB call can be accessed in a free band within a range not exceeding this band.

In order to realize this, CBR call and URB
As a conventional traffic control method for multiplexing calls, a CBR storing only CBR calls is used as shown in FIG.
UB storing only call cell buffer 702 and UBR calls
Two cell buffers, that is, an R call cell buffer 703, are provided, and the input cell is used as a CBR call / UBR call distribution unit 701.
The call is sorted according to the type of call to which the cell belongs, that is, whether it is a CBR call or a UBR call, and stored in the CBR call cell buffer 702 or the UBR call cell buffer 703.
The call is preferentially read from the call cell buffer 702 in the above-described CBR band.
Normally, control is performed such that the data is read out from the cell buffer 3 only when it is not read out from the CBR call cell buffer.

However, in an ATM ring system using an ATM line as a shared line of the entire network as shown in FIG. 8, each of the concentrator nodes (multiplexers) 801-1, 801-2, 801 constituting the network.
-3 according to the traffic control method described above in CBR
If the call and the UBR call are to be multiplexed, the UBR call input from the downstream and the UBR call transmitted by the local concentrator node device will be accumulated in one UBR call cell buffer. If the bandwidth of the UBR call that can be transferred simultaneously is viewed through the entire network, there is an unfairness between the hub node devices that the bandwidth that can be transferred becomes smaller as the hub node device is closer to the downstream hub node device, that is, the center node device 802.

For example, in the ATM ring system shown in FIG. 8, a plurality of concentrator nodes 801-1, 801
-2, 801-3 and center node device 802 are AT
The connection is made by connecting the center node device 802 to the wide area network 808 via the exchange 803. Here, the C of the ATM line 810 is connected.
The BR band is set to 90 Mbps, the UBR band is set to 60 Mbps, and each of the concentrator nodes 801-1, 801-2, 801
Assuming that the input UBR bands from the own concentrator node device at −3 are 60 Mbps, the UBR band from the concentrator node device 801-1 is 60 Mbps on the output side ATM line of the concentrator node device 801-1. In the ATM line on the output side of the concentrator node device 801-2, the UBR band of 60 Mbps is divided into two by the downstream concentrator node device and the concentrator node device 801-2, and the UBR band from the concentrator node device 801-1. Is 30
Mbps, the UBR band from the concentrator node device 801-2 becomes 30 Mbps, and furthermore, the concentrator node device 801-3.
In the ATM line on the output side of the above, the UBR band from the downstream line node device and the line node device 801-3 is divided into two, and the UBR band from the line node device 801-1 is 15 Mbp.
s, the UBR band from the concentrator node device 801-2 is 15
Mbps, the UBR band from the concentrator node device 801-3 becomes 30 Mbps, and as a result, the unfairness that the band that can be transferred becomes smaller as the downstream concentrator node device becomes smaller is the concentrator node device 801-1, 801-2, 801 -3
Will occur between.

[0007] By the way, the UBR call does not necessarily guarantee the communication band. However, when the ATM ring system is applied to a public network such as a subscriber access network, it depends on the position where the concentrator node device is located. The occurrence of unfairness in the bandwidth of UBR calls is a major problem.

[0008] Conventionally, in this type of apparatus, the communication quality is CBR class, rt-VBR (Variable Variable).
Bit Rate) class, nrt-VBR class, UBR 4
ABR (Available Bit Rate) for class or these
5 classes are added.

That is, a buffer is provided for each call request quality class, the corresponding class is determined based on the connection identifier, and a cell is written to the corresponding buffer based on this determination. It is configured to work.

[0010] Here, UBR traffic is a best-effort type that does not guarantee a band, and guarantees communication in a range where the band is free, so that processing related to the band is not normally performed.

In this type of system, if a GFR (Guaranteed Frame Rate) call that guarantees the lowest rate is supported, a new buffer must be provided to distinguish between a UBR call and a GFR call. According to this, there is a problem that the processing of hardware and software is greatly changed, and the changed configuration becomes large.

In order to solve this problem, UBR call and G
If the FR calls and the FR calls are mixed and stored in the buffer, it becomes necessary to distinguish between the UBR call and the GFR call. Therefore, in order to distinguish up to the minimum guaranteed rate of the GFR call, the UPC (Usag
e UB by parameter control
R is CLP (Cell Loss Priority)
Tagging LP1, GFR is MCR (Minimum Cell Rat
e: minimum cell transmission). A configuration in which tagging processing is performed is considered. However, in the UPC GCRA algorithm, there is a problem that tagging of all UCRs cannot be strictly performed.

Further, even if the MCR of the GFR can be distinguished when the UBR is mixed, since the band is not originally managed in the UBR, there is a problem that the band up to the MCR of the GFR cannot be guaranteed.

[0014]

As described above, in the conventional communication network system, if it is attempted to multiplex a CBR call and a UBR call in accordance with the above-described traffic control method in each of the concentrating node devices constituting the network, the input from the downstream is performed. The UBR call to be transmitted and the UBR call sent by the local concentrator node device are stored in one UBR call cell buffer, so that the bandwidth of the UBR call that can be simultaneously transferred from each concentrator node device is viewed through the entire network. There is a problem that unfairness that the transferable band becomes smaller as the downstream concentrator node device is generated between the concentrator node devices.

In addition, when GFR is newly supported, a large change in hardware or the like occurs, and the UBR is changed.
When GFR and GFR coexist, there is a problem that the MCR band cannot be strictly distinguished and the MCR band cannot be guaranteed.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a communication network system and a hub node device that do not cause unfairness in the bandwidth of a UBR call depending on the position where the hub node device is located.

Another object of the present invention is to provide a communication network system and a concentrator node device which can guarantee the MCR band of GFR even when UBR and GFR are mixed.

[0018]

In a communication network system according to the present invention, a plurality of concentrator nodes are connected in a ring via an ATM line. In a communication network system for multiplexing and outputting to an upstream concentrator node device, the concentrator node device distributes an input call into a CBR call that guarantees a communication band and a UBR call that does not necessarily guarantee a communication band. Means, a CBR call cell buffer for accumulating the CBR calls distributed by the first distribution means, and a second distribution for distributing the UBR calls distributed by the first distribution means for each originating concentrator node device. Means, a plurality of cell buffers for accumulating UBR calls distributed by the second distribution means for each of the outgoing concentrating node devices, and accumulating in the plurality of cell buffers A round-robin readout control means for sequentially reading the received UBR calls in a fair round-robin manner, and a CBR call stored in the CBR call cell buffer which is preferentially read out, and the UBR read-out by the fairness round robin readout control means. CBR call priority reading control means for outputting a call to the upstream concentrator node device.

Further, in the communication network system according to the present invention, a plurality of concentrator nodes are connected in a ring via an ATM line, and the concentrator node multiplexes a plurality of calls having different communication request qualities to upstream. In a communication network system for outputting to a concentrator node device, the concentrator node device includes a first distributing unit for distributing an input call into a CBR call that guarantees a communication band and a UBR call that does not necessarily guarantee a communication band; C distributed by the first distribution means
A CBR call cell buffer for storing a BR call;
Second distributing means for distributing the UBR calls distributed by the distributing means for each number of passing concentrating node devices, and a plurality of accumulating the UBR calls distributed for each number of passing concentrating node devices by the second distributing means. Cell buffer, fixed priority read control means for sequentially reading UBR calls stored in the plurality of cell buffers in a preset fixed priority system, and the CBR
CBR call priority readout control means for reading out the CBR call stored in the call cell buffer with priority and outputting the UBR call read out by the fixed priority readout control means to the upstream concentrator node device. I do.

Further, in the communication network system according to the present invention, a plurality of concentrator nodes are connected in a ring via an ATM line, and the concentrator node multiplexes a plurality of calls having different required communication qualities and upstream. In a communication network system for outputting to a concentrator node device, the concentrator node device includes a first distributing unit for distributing an input call into a CBR call that guarantees a communication band and a UBR call that does not necessarily guarantee a communication band; C distributed by the first distribution means
A CBR call cell buffer for storing a BR call;
Second distributing means for distributing the UBR call distributed by the distributing means for each virtual channel of the ATM line;
A plurality of cell buffers for storing the UBR calls distributed by the distribution means for each of the virtual channels; and a fair round robin read control means for sequentially reading out the UBR calls stored in the plurality of cell buffers in a fair round robin manner; CBR call priority reading control means for preferentially reading the CBR call stored in the CBR call cell buffer and outputting the UBR call read by the fair round robin reading control means to an upstream concentrator node device. It is characterized by.

Further, in the communication network system according to the present invention, a plurality of concentrator nodes are connected in a ring via an ATM line, and the concentrator node multiplexes a plurality of calls having different communication request qualities and upstream. In a communication network system for outputting to a concentrator node device, the concentrator node device includes a first distributing unit for distributing an input call into a CBR call that guarantees a communication band and a UBR call that does not necessarily guarantee a communication band; C distributed by the first distribution means
A CBR call cell buffer for storing a BR call;
Second distributing means for distributing the UBR call distributed by the distributing means for each virtual channel of the ATM line;
A plurality of cell buffers for accumulating the UBR calls distributed by the distribution means for each virtual channel, and a queue length priority method for sequentially reading out the UBR calls accumulated in the plurality of cell buffers by a queue length priority method for prioritizing an accumulation amount. Read control means;
CBR call priority reading control means for preferentially reading out the CBR call stored in the CBR call cell buffer and outputting the UBR call read by the queue length priority reading control means to an upstream concentrator node device. It is characterized by.

Further, in the communication network system according to the present invention, a plurality of concentrator nodes are connected in a ring via an ATM line, and the concentrator node multiplexes a plurality of calls having different communication request qualities and upstream. In the communication network system for outputting to the concentrator node device, the concentrator node device includes a distributing unit that classifies the input call according to communication request quality, and a cell related to the call classified by the distributing unit. It is characterized by comprising a cell buffer for accumulating for each class, and output control means for sequentially taking out the cells accumulated in the cell buffer and outputting the cells to the upstream concentrator node device.

Here, the output control means is characterized in that the cells stored in the cell buffer are sequentially taken out according to a fixed priority set in advance for each class and output to the upstream concentrator node device.

Further, the output control means is characterized in that cells stored in the cell buffer are sequentially read out in a round-robin manner and output to an upstream concentrator node device.

Monitoring means for monitoring a maximum cell transmission rate, an average cell transmission rate, and a minimum cell transmission rate permitted for a cell associated with a call classified according to a communication request quality by the distribution means; A control unit for executing a cell discarding process or a tagging process in accordance with the monitoring result of the monitoring unit.

Further, the distribution means distributes cells related to a plurality of best-effort calls having different communication qualities to the same class, and the output control means determines the priority of the cells distributed to the same class. A distinction is made based on the loss priority indication.

Rewriting means for rewriting the cell loss priority indication of a specific cell among the cells assigned to the same class; and means for returning the cell loss priority indication rewritten by the rewriting means to the original cell loss priority indication. Is further provided.

Further, the concentrator node device of the present invention has an AT
A CB that guarantees a communication band for an incoming call in a concentrator node device that is connected in a ring via an M line and multiplexes a plurality of calls having different communication request qualities and outputs the multiplexed call to an upstream side.
A first distribution unit for distributing the R call and a UBR call whose communication band is not necessarily guaranteed, a CBR call cell buffer for storing the CBR call distributed by the first distribution unit, and the first distribution Second distribution means for distributing the UBR call distributed by the means for each transmission concentrator node device, and a plurality of cell buffers for accumulating the UBR calls distributed by the second distribution means for each transmission concentrator node device; A fair round robin read control means for sequentially reading out the UBR calls stored in the plurality of cell buffers in a fair round robin manner; and preferentially reading out the CBR calls stored in the CBR call cell buffer, and CBR for outputting the UBR call read by the read control means to the upstream side
Call priority reading control means.

Further, the concentrator node device of the present invention has an AT
A CB that guarantees a communication band for an incoming call in a concentrator node device that is connected in a ring via an M line and multiplexes a plurality of calls having different communication request qualities and outputs the multiplexed call to an upstream side.
A first distribution unit for distributing the R call and a UBR call whose communication band is not necessarily guaranteed, a CBR call cell buffer for storing the CBR call distributed by the first distribution unit, and the first distribution Second distributing means for distributing the UBR calls distributed by the means for each number of passing concentrating node devices, and a plurality of cell buffers for accumulating the UBR calls distributed by the second distributing means for each number of passing concentrating node devices Fixed priority read control means for sequentially reading the UBR calls stored in the plurality of cell buffers in a preset fixed priority system, and priority reading of the CBR calls stored in the CBR call cell buffer, CBR call priority reading control means for outputting the UBR call read by the fixed priority reading control means to the upstream side.

Further, the line concentrator node device of the present invention
A CB that guarantees a communication band for an incoming call in a concentrator node device that is connected in a ring via an M line and multiplexes a plurality of calls having different communication request qualities and outputs the multiplexed call to an upstream side.
A first distribution unit for distributing the R call and a UBR call whose communication band is not necessarily guaranteed, a CBR call cell buffer for storing the CBR call distributed by the first distribution unit, and the first distribution Second distribution means for distributing the UBR calls distributed by the means for each virtual channel of the ATM line, and a plurality of cell buffers for accumulating the UBR calls distributed for each virtual channel by the second distribution means; A fair round robin read control means for sequentially reading out the UBR calls stored in the plurality of cell buffers in a fair round robin manner; and preferentially reading out the CBR calls stored in the CBR call cell buffer, CBR call priority reading control means for outputting the UBR call read by the reading control means to the upstream side.

Further, the concentrator node device of the present invention has an AT
A CB that guarantees a communication band for an incoming call in a concentrator node device that is connected in a ring via an M line and multiplexes a plurality of calls having different communication request qualities and outputs the multiplexed call to an upstream side.
A first distribution unit for distributing the R call and a UBR call whose communication band is not necessarily guaranteed, a CBR call cell buffer for storing the CBR call distributed by the first distribution unit, and the first distribution Second distribution means for distributing the UBR calls distributed by the means for each virtual channel of the ATM line, and a plurality of cell buffers for accumulating the UBR calls distributed for each virtual channel by the second distribution means; A queue length priority read control means for sequentially reading out the UBR calls stored in the plurality of cell buffers in a queue length priority system which prioritizes a storage amount; and a CBR stored in the CBR call cell buffer.
CB for reading the call preferentially and outputting the UBR call read by the queue length priority read control means to the upstream side
R call priority reading control means.

In addition, the concentrator node device of the present invention has an AT
A concentrating node device connected in a ring via the M line and multiplexing a plurality of calls having different required communication qualities and outputting the multiplexed calls to an upstream side; A cell buffer for accumulating cells related to calls classified by the distribution means for each class, and an output control means for sequentially extracting cells accumulated in the cell buffer and outputting the cells to an upstream concentrator node device. It is characterized by having.

Here, the output control means sequentially takes out the cells stored in the cell buffer according to a fixed priority preset for each class and outputs the cells to the upstream side.

Further, the output control means sequentially reads out cells stored in the cell buffer in a round robin manner and outputs the cells to an upstream concentrator node device.

Monitoring means for monitoring a maximum cell transmission rate, an average cell transmission rate, and a minimum cell transmission rate permitted for a cell associated with a call classified according to the communication request quality by said distribution means; A control unit for executing a cell discarding process or a tagging process in accordance with the monitoring result of the monitoring unit.

Further, the distribution means distributes cells related to a plurality of best effort type calls having different communication qualities to the same class, and the output control means determines the priority of the cells distributed to the same class. A distinction is made based on the loss priority indication.

Rewriting means for rewriting the cell loss priority indication of a specific cell among the cells allocated to the same class; and means for returning the cell loss priority indication rewritten by the rewriting means to the original cell loss priority indication. Is further provided.

[0038]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a communication network system and a hub node device according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram showing a first embodiment of a concentrator node device employed in a communication network system according to the present invention.

The concentrator node device shown in FIG. 1 corresponds to each of a plurality of concentrator node devices arranged on an ATM line constituting an ATM ring in the ATM ring system as shown in FIG.

This concentrator node device inputs the cell flow from the downstream node (concentrator node device) and the cell flow from its own node, and sorts the cell for the CBR call and the cell for the UBR call based on the connection identifier. CBR call / UBR call distribution unit 101, CBR call / UBR call distribution unit 1
C that stores cells related to the CBR call distributed in 01
A cell buffer 102 for a BR call, a cell relating to a UBR call distributed by the CBR call / UBR distribution unit 101 is input, and a transmission node distribution unit 103 which distributes a cell relating to the UBR call for each transmission node, a transmission node distribution unit 103 A plurality of cell buffers (cell buffer 104-1 for the transmission node 1,..., Cell buffer 10 for the transmission node N) for accumulating the cells distributed for each transmission node in the distribution unit 103 for each transmission node.
4-N), cell buffer 104-1, for source node 1
.. Fair round robin read control section 105 for reading out cells stored in cell buffer 104-N for source node N in a fair round robin manner, cell buffer 1 for CBR call
02, the cell stored in the CBR call cell buffer 102 and the cell read by the fair round robin read control unit 105 are read out with priority given to the cell stored in the CBR call cell buffer 102. It comprises a CBR call priority reading control unit 106 which outputs as a cell stream.

Here, the cell buffer 10 for the transmitting node 1
4-1 ... cell buffer 104-N for source node N
Are provided as many as the number N of nodes on the ATM ring in which the concentrator node device is arranged. The originating node distributing section 103 distributes cells related to the UBR call by their originating nodes, 1,... Are stored in the source node N cell buffer 104-N for each source node.

According to such a configuration, in each concentrator node device on the ATM ring, cells related to the UBR call are accumulated in the cell buffer for each originating node, and the accumulated cells are read out in a fair round robin manner. Since it is multiplexed with the cell related to the UBR call and becomes the cell flow to the upstream node, it is possible to eliminate the access unfairness between the nodes regarding the cell related to the UBR call.

FIG. 2 is a block diagram showing a second embodiment of the concentrator node device employed in the communication network system according to the present invention.

This concentrator node device inputs a cell flow from a downstream node (concentrator node device) and a cell flow from its own node, and distributes the cell for a CBR call and the cell for a UBR call based on the connection identifier. CBR call / UBR call distributor 201, CBR call / UBR call distributor 2
C that stores cells related to the CBR call distributed in 01
The cell buffer 202 for BR call, the cell related to the UBR call allocated by the CBR call / UBR call distribution unit 201 is input, and the cell related to this UBR call is allocated according to the number of passing nodes per call. A plurality of cell buffers (cell buffer (cell buffer 1) 204-
,... Cell buffer 204-M (cell buffer M)), cell buffer 204-1,. The cells stored in the CBR call cell buffer 202 and the cells read by the fixed-priority read control unit 205 are read by giving priority to the cells stored in the CBR call cell buffer 202, and the read cells are multiplexed. It comprises a CBR call priority reading control unit 206 that outputs a cell flow to an upstream node as a cell flow.

Here, the per-call passing node number distribution unit 203
Distributes a cell related to a UBR call according to the number of nodes that have passed through to its own node,
4-1... Are stored in the cell buffer 204-M according to the number of passing nodes for each call.

For example, a plurality of cell buffers 204-1,
.. Cell buffer 204-M having four cell buffers 204-1, 204-2, 204-3, and 20
4-4, the cell buffer cell buffer 20
4-1 stores cells having 1 to 6 passing nodes, cell buffer 204-2 stores cells having 7 to 12 passing nodes, and cell buffer cell buffer 204-3 stores cells passing therethrough. Cells having 13 to 18 nodes are stored, and cells having 19 or more passing nodes are stored in the cell buffer 204-4.

Then, the fixed priority read control unit 205
Cell buffer Cell buffer 204-4 (high priority) → Cell buffer Cell buffer 204-3 → Cell buffer Cell buffer 204-2 → Cell buffer Cell buffer 204-
The cells are read out in the order of 1 (low priority) by the fixed priority method.

According to such a configuration, the unfairness of the transferable band due to the number of passing nodes of the cell related to the UBR call is equalized, and the access unfairness among the nodes related to the cell related to the UBR call is eliminated. can do.

FIG. 3 is a block diagram showing a third embodiment of the hub node device employed in the communication network system according to the present invention.

This concentrator node device inputs a cell flow from a downstream node (concentrator node device) and a cell flow from its own node, and distributes the cell for a CBR call and the cell for a UBR call based on the connection identifier. CBR call / UBR call divider 301, CBR call / UBR call divider 3
C that stores cells related to the CBR call distributed in 01
A cell relating to the UBR call distributed by the BR call cell buffer 302 and the CBR call / UBR call distribution unit 301 is input, and the cell relating to the UBR call is inputted for each call on the ATM ring.
In other words, the per-VC distribution unit 303 that distributes each VC (Virtual Channel),
A plurality of cell buffers (cell buffer (cell buffer 1) 304-) for accumulating cells sorted for each C for each VC.
1,... Cell buffer 304-L (cell buffer L)), cell buffers 304-1,..., A fair round robin readout control unit 305 for reading out cells stored in cell buffer 304-L in a fair round robin manner. , CB
The cells stored in the CBR call cell buffer 302 and the cells read by the fair round-robin read control unit 305 are read with priority given to the cells stored in the R call cell buffer 302, and the read cells are multiplexed. And a CBR call priority reading control unit 306 that outputs the cell as a cell flow to the upstream node.

Here, the per-VC distributing unit 303 distributes the cell related to the UBR call for each VC, and
04-1,... In the cell buffer 304-L, for each VC,
That is, VC = x1,..., VC = xl, and the cells stored in the cell buffers 304-1,..., Cell buffer 304-L for each VC are stored in the fair round-robin readout control unit 305 by the fair round-robin method. , And multiplexes with the cell related to the UBR call, and outputs it to the upstream node as a cell stream.

According to such a configuration, the cells related to the UBR call are separated and accumulated for each VC, and are then multiplexed fairly, so that the access unfairness between the nodes regarding the cells related to the UBR call is eliminated. Can be.

FIG. 4 is a block diagram showing a fourth embodiment of the hub node device employed in the communication network system according to the present invention.

This concentrator node device inputs the cell flow from the downstream node (concentrator node device) and the cell flow from its own node, and sorts the cell for the CBR call and the cell for the UBR call based on the connection identifier. CBR call / UBR call distributor 401, CBR call / UBR call distributor 4
C that stores cells related to the CBR call distributed in 01
The cell for the BR call 402, the cell for the UBR call distributed by the CBR call / UBR call distribution unit 401 is input, and the cell for the UBR call is input for each call on the ATM ring.
That is, the per-VC distributing unit 403 that distributes for each VC (Virtual Channel),
A plurality of cell buffers (cell buffer (cell buffer 1) 404-) for accumulating cells sorted for each C for each VC
1,... Cell buffer 404-L (cell buffer L)), cell buffer 404-1,..., Queue length priority read control unit 405 for reading out cells stored in cell buffer 404-L in a queue length priority system. , The cells stored in the CBR call cell buffer 402 and the cells read by the queue length priority read control unit 405 are read with priority given to the cells stored in the CBR call cell buffer 402, and the read cells are multiplexed. And a CBR call priority readout control unit 406 that outputs the data as a cell flow to the upstream node.

The fourth embodiment is different from the third embodiment in that a plurality of cell buffers 304-1,
... In the cell buffer 304-L, every VC, that is, V
C = x1,... VC = xl, and the fair round-robin read control unit 305 reads the data in a fair round-robin manner, whereas a plurality of cell buffers 404-1,. In the buffer 404-L,
The cells stored for each VC are stored in a queue length priority system,
Cell buffer 404-1,... Cell buffer 404-
The cell read control is performed while sequentially changing the cell buffer of L having a large cell accumulation amount so as to be preferentially read.

According to such a configuration, cells involved in a UBR call are separated and stored for each VC, and a cell buffer having a large cell storage amount is preferentially read and multiplexed. It is possible to eliminate access unfairness between nodes regarding the cell.

FIG. 5 is a block diagram showing a fifth embodiment of the hub node device employed in the communication network system according to the present invention.

In the concentrating node device shown in FIG.
Then, based on the connection identifier, the cell is sorted into a cell related to the CBR call, a cell related to the Rt-VBR call, a cell related to the nRt-VBR call, a cell related to the UBR call, and a cell related to the GFR.

The cell related to the CBR call sorted by the connection identifying unit 501 is a PCR (Peak Cell).
(Rate: maximum cell transmission rate) The UPC processing is performed by the monitoring unit 502, and the result is accumulated in the buffer 808-2 assigned to the CBR class of the cell buffer 508.

The cell related to the Rt-VBR call sorted by the connection identification unit 501 is a PCR / SCR
(Sustainable Cell Rate: Average Cell Transmission Rate)
-Stored in the buffer 808-1 assigned to the VBR class.

The cell related to the nRt-VBR call sorted by the connection identifying unit 501 is a PCR / SC
The cell buffer 50 is subjected to the UPC processing by the R
Buffer assigned to nRt-VBR class of 8
08-3.

The cell related to the UBR call sorted by the connection identification unit 501 is subjected to the UPC processing by the PCR monitoring unit 505 and then tagged by the CLP changing unit 507 to the CLP 1, and the UBR / GFR of the cell buffer 508.
The data is accumulated in the buffer 808-4 assigned to the class.

The cell related to the GFR call distributed by the connection identification unit 501 is subjected to the UPC processing by the PCR / MCR monitoring unit 506, and the UB of the cell buffer 508 is processed.
Buffer 808-4 assigned to R / GFR class
Is accumulated in

Here, the UP in the PCR monitoring unit 502
The C process is monitored by PCR. Here, cells above the PCR are discarded, and cells below the PCR pass.

The UPC process in the PCR / SCR monitor 503 is monitored by the PCR and the SCR.
Here, cells of PCR or more and CLP0 of SCR or more
Are discarded, and cells under PCR and cells under CLP0 under SCR pass.

The UPC process in the PCR / SCR monitor 504 is monitored by the PCR and the SCR.
Here, cells of PCR or more and CLP0 of SCR or more
Are discarded and cells below PCR and CL below SCR
The cell at P0 passes.

The UPC in the PCR monitor 505
The process is monitored by PCR, where cells above the PCR are discarded, cells below the PCR pass, and
Since the cell related to the UBR call does not need to guarantee the band, C
The LP change unit 507 tags the CLP1.

The UPC processing of the cell related to the GFR call in the PCR / MCR monitoring unit 506 includes the PCR and the MCR.
PCR <GFR band: discarded PCR ≧ GFR band ≧ MCR: tagging (CLP0 → C
LP1) MCR> GFR band: Passed (still CLP0).

That is, cells above the PCR are discarded,
Cells with a MCR or more and a PCR or less need not be guaranteed a band, and are therefore tagged by CLP1. Also, cells below the MCR are passed through as CLP0 to guarantee the band.

That is, in the GFR class, up to the MCR that guarantees the band is distinguished by CLP0 / 1. Here, CLP1 is a class that is preferentially discarded during congestion.

FIG. 6 shows the UBR call and GF shown in FIG.
It is the figure which showed the UPC process with respect to R call in the graph.

FIG. 6A shows a UPC for a UBR call.
FIG. 6B illustrates a UPC process for a GFR call.

That is, for UBR calls, all CL
Since tagging is performed on CLP1 by the P change unit 507, the PC
R cells or more are discarded.

For a GFR call, cells above the PCR are discarded, and cells below the MCR and below the PCR are
Although cells are tagged at P1, cells below MCR are passed through as CLP0, so cells below MCR have guaranteed bandwidth.

Returning to FIG. 5, the cells stored in the cell buffer 508 by classifying as described above have the CtR class as the highest priority, the Rt-VBR class, and the other n.
The Rt-VBR class and the UBR / GFR class are output in a fixed priority order, and the nRt-VBR class and the UBR / GFR class are output in a round robin manner.

As a specific example, in a 150M band, CB
R, Rt-VBR baking 90M use, GFR MCR
Is 10M, if the above-mentioned 90M fixedly used out of 150M is secured, the remainder will be 60M of medicine. This bandwidth is used by best effort traffic,
In order to secure 10 M of the MFR of the GFR, the round robin cannot guarantee the 10 M of the MFR of the GFR unless the GFR is selected once every six times.

In this case, the round robin ratio is nRt
-VBR: UBR / GFR = 5: 1. Since the MCR is actually the lowest guaranteed band, the round robin ratio satisfying the above ratio is defined as nRt-VBR: UBR /
It can be performed with GFR = 2: 1.

[0079]

As described above, according to the present invention,
1) It is possible to eliminate unfairness in the bandwidth of the UBR call caused by the position where the concentrator node device is located. 2) U
Even when BR and GFR are mixed, there is an effect that the MCR band of GFR can be guaranteed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of a concentrator node device employed in a communication network system according to the present invention.

FIG. 2 is a block diagram showing a second embodiment of the hub node device employed in the communication network system according to the present invention.

FIG. 3 is a block diagram showing a third embodiment of a concentrator node device employed in a communication network system according to the present invention.

FIG. 4 is a block diagram showing a fourth embodiment of a concentrator node device employed in a communication network system according to the present invention.

FIG. 5 is a block diagram showing a fifth embodiment of a concentrator node device employed in a communication network system according to the present invention.

FIG. 6 is a graph showing a UPC process for the UBR call and the GFR call shown in FIG. 5;

FIG. 7 is a block diagram showing a conventional concentrator node device employed in a communication network system.

8 is a system diagram showing an example of an ATM ring system using the concentrator node device shown in FIG.

[Explanation of symbols]

Reference Signs List 101 CBR call / UBR call distributing unit 102 CBR call cell buffer 103 originating node distributing unit 104-1 originating node 1 cell buffer 104 -N originating node N cell buffer 105 fair round robin read control unit 106 CBR call priority Read control unit 201 CBR call / UBR call distribution unit 202 CBR call cell buffer 203 Call passing node number distribution unit 204-1 cell buffer 1 204-M cell buffer M 205 Fixed priority read control unit 206 CBR call priority read Control unit 301 CBR call / UBR call distribution unit 302 CBR call cell buffer 303 VC distribution unit 304-1 cell buffer 1 304-L cell buffer L 305 Fair round-robin read control unit 306 CBR call priority read control unit 401 CBR call / UBR call distribution section 402 CBR call cell Buffer 403 per-VC distribution unit 404-1 cell buffer 1 404-L cell buffer L 405 queue length priority read control unit 406 CBR call priority read control unit 501 connection identification unit 502 PCR monitoring unit 503 PCR / SCR monitoring unit 504 PCR / SCR monitoring unit 505 PCR / MCR monitoring unit 507 CLP1 conversion unit 508 cell buffer 701 CBR call / UBR call distribution unit 702 CBR call cell buffer 703 UBR call cell buffer 704 CBR call priority read control unit 801-1, 801- 2, 801-3 Concentration node device 802 Center node device 803 Switchboard 804 Wide area network

Claims (20)

[Claims] 1. A communication network in which a plurality of concentrator node devices are connected in a ring via an ATM line, and the concentrator node devices multiplex a plurality of calls having different communication request qualities and output the multiplexed calls to an upstream concentrator node device. In the system, the concentrator node device includes: a first distribution unit that distributes an input call into a CBR call that guarantees a communication band and a UBR call that does not necessarily guarantee a communication band; C that stores the CBR calls
A cell buffer for BR call; a second distribution unit for distributing the UBR call distributed by the first distribution unit for each transmission concentrator node device; and the transmission of the UBR call distributed by the second distribution unit. A plurality of cell buffers stored for each concentrator node device; a fair round robin read control means for sequentially reading the UBR calls stored in the plurality of cell buffers in a fair round robin manner; and a plurality of cell buffers stored in the CBR call cell buffer. A communication network system, comprising: a CBR call priority readout control unit for reading out a CBR call with priority and outputting the UBR call read out by the fair round robin readout control unit to an upstream concentrator node device. 2. A communication network in which a plurality of concentrator node devices are connected in a ring via an ATM line, and the concentrator node devices multiplex a plurality of calls having different communication request qualities and output the multiplexed calls to an upstream concentrator node device. In the system, the concentrator node device includes: a first distribution unit that distributes an input call into a CBR call that guarantees a communication band and a UBR call that does not necessarily guarantee a communication band; C that stores the CBR calls
A BR call cell buffer, a second distribution unit that distributes the UBR call distributed by the first distribution unit for each number of passing line concentrator nodes, and a UBR call distributed by the second distribution unit. A plurality of cell buffers stored for each number of passing line concentrator nodes; fixed priority read control means for sequentially reading UBR calls stored in the plurality of cell buffers in a preset fixed priority system; and a CBR call cell buffer. CBR call which reads out the CBR call stored in the PBR preferentially and outputs the UBR call read out by the fixed priority reading control means to the upstream concentrator node device.
A communication network system comprising: BR call priority reading control means. 3. A communication network in which a plurality of concentrator node devices are connected in a ring via an ATM line, and the concentrator node devices multiplex a plurality of calls having different communication request qualities and output the multiplexed calls to an upstream concentrator node device. In the system, the concentrator node device includes: a first distribution unit that distributes an input call into a CBR call that guarantees a communication band and a UBR call that does not necessarily guarantee a communication band; C that stores the CBR calls
The BR call cell buffer and the UBR call distributed by the first distribution means are transmitted to the ATM
A second distributing unit that distributes each virtual channel of the line, a plurality of cell buffers that accumulate the UBR calls distributed by the second distributing unit for each virtual channel, and a plurality of cell buffers that accumulate in the plurality of cell buffers. A fair round robin read control means for sequentially reading out UBR calls in a fair round robin manner; and a CBR call stored in the CBR call cell buffer with priority reading, and a UBR call read by the fair round robin read control means. A communication network system comprising: CBR call priority reading control means for outputting to an upstream concentrator node device. 4. A communication network in which a plurality of hub nodes are connected in a ring via an ATM line, and the hub nodes multiplex a plurality of calls having different required communication qualities and output the multiplexed calls to an upstream hub node. In the system, the concentrator node device includes: a first distribution unit that distributes an input call into a CBR call that guarantees a communication band and a UBR call that does not necessarily guarantee a communication band; C that stores the CBR calls
The BR call cell buffer and the UBR call distributed by the first distribution means are transmitted to the ATM
A second distributing unit that distributes each virtual channel of the line, a plurality of cell buffers that accumulate the UBR calls distributed by the second distributing unit for each virtual channel, and a plurality of cell buffers that accumulate in the plurality of cell buffers. A queue length priority reading control means for sequentially reading out the UBR calls in a queue length priority system which prioritizes the storage amount; and a CBR call stored in the CBR call cell buffer which is read out preferentially. A communication network system comprising: CBR call priority reading control means for outputting a read UBR call to an upstream concentrator node device. 5. A communication network in which a plurality of concentrating node devices are connected in a ring via an ATM line, and the concentrating node devices multiplex a plurality of calls having different communication request qualities and output the multiplexed calls to an upstream concentrating node device. In the system, the concentrator node device includes: a distribution unit that classifies an input call according to a communication request quality; and a cell buffer that accumulates a cell related to the call classified by the distribution unit for each class. An output control means for sequentially taking out the cells stored in the cell buffer and outputting the cells to an upstream concentrator node device. 6. The output control means according to claim 5, wherein the cells stored in the cell buffer are sequentially taken out according to a fixed priority set in advance for each class and output to an upstream concentrator node device. The communication network system as described. 7. The communication network system according to claim 5, wherein said output control means sequentially reads out cells stored in said cell buffer in a round-robin manner and outputs the cells to an upstream concentrator node device. 8. A monitoring means for monitoring a maximum cell transmission rate, an average cell transmission rate, and a minimum cell transmission rate permitted for a cell associated with a call classified according to a communication request quality by said distribution means, 6. The communication network system according to claim 5, further comprising control means for executing a cell discarding process or a tagging process in accordance with a monitoring result of the monitoring unit. 9. The distributing means distributes cells related to a plurality of best effort type calls having different communication qualities to the same class, and the output control means determines a priority of the cells distributed to the same class by a cell. 6. The communication network system according to claim 5, wherein the distinction is made based on the loss priority indication. 10. Rewriting means for rewriting the cell loss priority indication of a specific cell among the cells allocated to the same class, and means for returning the cell loss priority indication rewritten by the rewriting means to the original cell loss priority indication. The communication network system according to claim 9, further comprising: 11. A concentrator node device connected in a ring via an ATM line and multiplexing a plurality of calls having different communication request qualities and outputting the multiplexed calls to an upstream side, wherein a CBR for guaranteeing a communication band for the inputted calls. First distributing means for distributing calls and UBR calls whose communication band is not necessarily guaranteed; and C for accumulating the CBR calls distributed by the first distributing means.
A cell buffer for BR call; a second distribution unit for distributing the UBR call distributed by the first distribution unit for each transmission concentrator node device; and the transmission of the UBR call distributed by the second distribution unit. A plurality of cell buffers stored for each concentrator node device; a fair round robin read control means for sequentially reading the UBR calls stored in the plurality of cell buffers in a fair round robin manner; and a plurality of cell buffers stored in the CBR call cell buffer. CB for reading out the CBR call with priority and outputting the UBR call read out by the fair round robin reading control means to the upstream side
A line concentrator node device comprising: R call priority reading control means. 12. A concentrator node device connected in a ring via an ATM line and multiplexing a plurality of calls having different required communication qualities and outputting the multiplexed calls to an upstream side, wherein a CBR for guaranteeing a communication band for the inputted calls. First distributing means for distributing calls and UBR calls whose communication band is not necessarily guaranteed; and C for storing the CBR calls distributed by the first distributing means.
A BR call cell buffer, a second distribution unit that distributes the UBR call distributed by the first distribution unit for each number of passing line concentrator nodes, and a UBR call distributed by the second distribution unit. A plurality of cell buffers stored for each number of passing line concentrator nodes; fixed priority read control means for sequentially reading UBR calls stored in the plurality of cell buffers in a preset fixed priority system; and a CBR call cell buffer. And a CBR call priority reading control means for reading out the CBR call stored in the fixed priority reading control means and outputting the UBR call read by the fixed priority reading control means to the upstream side. 13. A concentrator node device connected in a ring via an ATM line and multiplexing a plurality of calls having different required communication qualities and outputting the multiplexed calls to an upstream side, wherein a CBR for guaranteeing a communication band for the inputted calls. First distributing means for distributing calls and UBR calls whose communication band is not necessarily guaranteed; and C for accumulating the CBR calls distributed by the first distributing means.
The BR call cell buffer and the UBR call distributed by the first distribution means are transmitted to the ATM
A second distributing unit that distributes each virtual channel of the line, a plurality of cell buffers that accumulate the UBR calls distributed by the second distributing unit for each virtual channel, and a plurality of cell buffers that accumulate in the plurality of cell buffers. A fair round robin read control means for sequentially reading out UBR calls in a fair round robin manner; and a CBR call stored in the CBR call cell buffer with priority reading, and a UBR call read by the fair round robin read control means. CB output to upstream side
A line concentrator node device comprising: R call priority reading control means. 14. A concentrator node device connected in a ring via an ATM line and multiplexing a plurality of calls having different required communication qualities and outputting the multiplexed calls to an upstream side, wherein a CBR for guaranteeing a communication band for the inputted calls. First distributing means for distributing calls and UBR calls whose communication band is not necessarily guaranteed; and C for storing the CBR calls distributed by the first distributing means.
The BR call cell buffer and the UBR call distributed by the first distribution means are transmitted to the ATM
A second distributing unit that distributes each virtual channel of the line, a plurality of cell buffers that accumulate the UBR calls distributed by the second distributing unit for each virtual channel, and a plurality of cell buffers that accumulate in the plurality of cell buffers. A queue length priority reading control means for sequentially reading out the UBR calls in a queue length priority system which prioritizes the storage amount; and a CBR call stored in the CBR call cell buffer which is read out preferentially. A line concentrator node device comprising: CBR call priority read control means for outputting the read UBR call to the upstream side. 15. A concentrator node device connected in a ring via an ATM line and multiplexing a plurality of calls having different required communication qualities and outputting the multiplexed calls to an upstream side, wherein the incoming calls are classified according to the required communication qualities. A cell buffer for accumulating cells associated with calls classified by the distributing means for each class; and sequentially taking out the cells stored in the cell buffer and outputting the cells to the upstream concentrator node device. A communication network system comprising output control means. 16. The apparatus according to claim 15, wherein said output control means sequentially takes out cells stored in said cell buffer according to a fixed priority set in advance for each class and outputs the cells to an upstream side. Concentrator node device. 17. The line concentrator node device according to claim 15, wherein said output control means sequentially reads out cells stored in said cell buffer in a round robin manner and outputs the cells to an upstream line concentrator node device. 18. Monitoring means for monitoring a maximum cell transmission rate, an average cell transmission rate, and a minimum cell transmission rate permitted for a cell associated with a call classified according to communication request quality by said distribution means, 16. The line concentrator node device according to claim 15, further comprising control means for executing a cell discarding process or a tagging process in accordance with a monitoring result of the monitoring unit. 19. The distributing means distributes cells related to a plurality of best effort type calls having different communication qualities to the same class, and the output control means determines the priority of the cells distributed to the same class by a cell. 16. The line concentrator node device according to claim 15, wherein the discrimination is made based on the loss priority display. 20. Rewriting means for rewriting the cell loss priority indication of a specific cell among the cells allocated to the same class, and means for returning the cell loss priority indication rewritten by the rewriting means to the original cell loss priority indication. 20. The line concentrator node device according to claim 19, further comprising: