JP2001024658A - Method and device for regulating incoming call and recording medium with recording program for executing the method recorded therein - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent throughput from being lowered by turning off bits of each traffic sort in a flag stored in an outgoing resource availability IG concerned with a certain link and executing flooding and regulating incoming by traffic sorts. SOLUTION: Whether the number of counted calls reaches a preset value is decided. When the number of counted calls reaches the preset value, bits of a traffic sort concerned with an RAIG flag in outgoing resource availability IGs in both the horizontal links IG and Uplinks IG are turned off and flooding is executed by a flooding control processing part 14. Thereby incoming of the traffic sort concerned is deemed as being regulated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD OF THE INVENTION

The present invention relates to an ATM (Asynchronous Transfe
r Mode: Asynchronous transfer mode) The present invention relates to a method and apparatus for restricting incoming calls in an exchange such as an exchange, and particularly to a PNNI (Priva
1. Field of the Invention The present invention relates to a method and a device for restricting incoming calls of an exchange (node) corresponding to a te Network Network Interface) protocol, and a recording medium on which a program for executing the method is controlled.

[0003]

2. Description of the Related Art In an ATM exchange, it is necessary to provide an incoming call control function in order to avoid congestion in an ATM network or the like. 2. Description of the Related Art Conventionally, when trying to restrict incoming calls, upon receiving a call setup message from a terminal or another exchange, the number of calls of a requested traffic type is checked. Here, the traffic type is a service category in the ATM forum, and at present, CBR (Consta
nt Bit Rate: constant bit rate), non-real-time V
BR (Variable Bit Rate), real-time VBR, ABR (Available Bit Rate: dynamically changed bit rate), UBR (Unspecified Bit Rat)
e: unspecified bit rate).

FIG. 8 is a block diagram showing the configuration of hardware and software provided inside the exchange for executing the conventional incoming call restriction method. FIG. 9 is a block diagram showing the incoming call restriction determination processing unit 103 in FIG. 6 is a flowchart showing the operation of the embodiment.

[0005] A call control message control unit 101 for receiving a call control message from another exchange or terminal and transmitting the call control message to the other exchange or terminal, and connecting to the call control message control unit 101 to regulate incoming calls. And a control unit 102 for performing control for performing the control. Here, the call control message includes a call setup message and a call release message. An incoming call restriction determination processing unit 1 for determining whether or not to restrict incoming calls is provided inside the control unit 102.
03 and a call control processing unit 104 for controlling a call. Actually, the control unit 102 is configured as a computer, and reads a program for realizing processing to be performed by the incoming call restriction determination processing unit 103 and processing to be performed by the call control unit 104 from the recording medium 105. By executing this program, a process for incoming call control is executed.

Next, the operation of the conventional incoming call control method will be described with reference to the flowchart of FIG.

[0007] When a call setting message is received from another exchange, the call control processing section 104 inquires of the incoming call restriction determination processing section 103 whether or not to restrict incoming calls. The incoming call restriction determination processing unit 103 determines whether the number of calls on the link for which a call of the requested traffic type is to be established has reached a preset value (step 111).
If the number of calls on the link attempting to establish a call of the requested traffic type has not reached the preset value,
The incoming call restriction determination processing unit 103 counts up the number of calls on the link for which a call of the requested traffic type is to be established (step 112), and sets "OK" in the return value (return value) to perform the call control process. Returned to unit 104 (step 113). On the other hand, in step 111, if the number of calls on the link for which a call of the requested traffic type is to be established has reached a preset value, "NG" is entered in the return value and the call control processing unit 104 (Step 104). The call control processing unit 104 executes a sequence for establishing a call when the return value from the incoming call restriction determination procedure 103 is “OK”, and executes a call rejection sequence when the return value is “NG”.

[0008]

In the prior art described above, if the number of calls of a certain traffic type on a certain link has already reached the number of calls predetermined for that traffic type, Since the process of rejecting the call setup message of the call of the traffic type of the link operates, when the call setup message of the call of the traffic type of the link is received from another exchange, the processing capacity is reduced. There is a point.

[0009] An object of the present invention is to provide an incoming call that does not reduce the processing capability even if the number of calls of a certain traffic type on a certain link has already reached the number of calls predetermined for that traffic type. An object of the present invention is to provide a regulation method and device.

[0010]

An incoming call control method according to the present invention is an incoming call control method in a network according to the PNNI protocol, wherein the number of calls of a certain traffic type on a link is predetermined for each traffic type. Outgoing res associated with the link when the number is reached
ource availability Flood is performed by turning off the bit of the traffic type in the RAIG flag in the IG, thereby restricting the incoming call of the traffic type on the link.

[0011] That is, according to the incoming call control method, when the number of calls of a certain traffic type on a certain link exceeds a predetermined number, the horizontal L of the link is set.
Outgoing resource availa in inksIG and Uplinks IG
Turn off the bit of the corresponding traffic type in the RAIG flag in the bility IG and set the Horizontal Links IG and Uplin
Flood ks IG suppresses call setup messages for calls of that traffic type on that link from other exchanges. Therefore, incoming call restriction can be performed without lowering the processing capacity.

Further, in the present invention, the state in which the incoming call is regulated as described above (the state in which the number of calls of a certain traffic type on a certain link has reached a predetermined number for each traffic type). )), When the number of calls of the traffic type falls below the predetermined number, the outgoing resource availa
Preferably, flooding is performed by turning on the bit of the corresponding traffic type in the RAIG flag in the bility IG, thereby canceling the incoming call restriction of the traffic on the link. With this configuration, when the number of calls of a certain traffic type on a certain link is less than the predetermined number from the state where the number of calls of the certain traffic type is higher than the predetermined number, Within the Horizontal Links IG and Upl of the link
inks Outgoing resource availability in IG R in IG
By turning on the bit of the corresponding traffic type in the AIG flag to flood the Horizontal Links IG and Uplinks IG, the suppression of transmission of the call setting message of the traffic type of the link from another switch is released, The incoming call restriction is released.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, preferred embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing a configuration of an incoming call restriction device according to an embodiment of the present invention.

The termination control device shown in FIG. 1 is provided inside an exchange corresponding to the PNNI protocol, and is a unit of data managed by a topology database used in the PNNI protocol, PTSE (PNNI).
PTSE transmitting / receiving unit 11 for receiving Topology State Element) from another exchange or transmitting it to another exchange
A call control message transmitting / receiving unit 12 for receiving a call control message from another exchange or transmitting the call control message to another exchange.
And a control unit 13 arranged between the PTSE transmission / reception unit 11 and the call control message transmission / reception unit 12 for controlling the execution of the incoming call restriction based on the present invention. The control unit 13 includes a flood control processing unit 14 for controlling transmission and reception of a topology database used in the PNNI protocol, and a horizontal control IG and a U.S.
plinks Outgoing Resource Availability in IG RAIG flag control processing unit 1 for controlling the RAIG flag in IG
5 and a call control processing unit 16 for controlling a call. In practice, the control unit 13 can be configured as a computer. That is, a program for realizing the processing in each of the flooding control processing unit 14, the RAIG flag control processing unit 15, and the call control processing unit 16 is recorded in the recording medium 17 in advance, and the recording medium 17
Thus, by reading these programs into the control unit 13 and executing the programs, the control unit 13 that performs control for executing incoming call barring can be realized.

Here, in order to facilitate understanding of the present invention, PN
The NI protocol will be described.

In a network based on the PNNI protocol, when a certain exchange (called a “node” in the PNNI protocol) receives a call message from a terminal, it determines a node accommodating the called number contained in the message and sends the call to that node. (Which is called the DTL), and includes that DTL in the outgoing message,
To the next node according to. The node that has received the call message transmits the call message to the next node according to the DTL included in the node. This is repeated, and the calling message is conveyed to the node accommodating the called number, and finally arrives at the terminal of the called number.

As described above, the outgoing call message is transferred in the network based on the DTL. In order to create the DTL used here, in the PNNI protocol, the node has any function and is connected to any node. Is exchanged between all nodes. The procedure for exchanging this data is called flooding, and the Hori used in the present invention is included in this data.
Includes zontal Links IG and Uplinks IG. Therefore, in the PNNI protocol, all nodes have data on all nodes. However, a large amount of memory is required to hold data on all nodes, and it becomes virtually impossible to hold data when the network becomes large. Therefore, a group of a plurality of nodes is made to appear logically as one node, thereby reducing the data amount. Therefore, each node has a level value so that nodes having the same level value can be grouped. In addition, logical nodes generated by the grouping have lower level values.

FIG. 2A shows an example of the configuration of a network. Here, nodes are represented by circles (○). In the illustrated example, there are five nodes A1, A2, A3, B1, and B2 (all have a level value of 96). Then, a logical node A is created by grouping the nodes A1, A2, and A3, and a logical node B is created by grouping the nodes B1 and B2. Assuming that the level values of the nodes A and B are 88, the logical network configuration is as shown in FIG.

In the PNNI protocol, a link between adjacent nodes at the same level is defined as a HorizontalLink (horizontal link).
Call. In the example shown in FIG. 2B, between A1 and A2,
The links between A2 and A3, between B1 and B2, and between AB are
rizontal Link. Also, nodes A1, A
The network seen from A2 and A3 is as shown in FIG. Here, the link between A3 and B is referred to as Uplink. That is, Uplink means a link between adjacent nodes at different levels. Conversely, node B
When the network configuration is viewed from B1 and B2, B1-A
The link between them becomes Uplink.

The Horizontal Links IG and Uplinks IG are:
These are data relating to Horizontal Link and Uplink, respectively, and indicate the link between which node, which node indicates the type of traffic that can pass, and the available bandwidth. Horizontal L
The specific formats of the inks IG and Uplinks IG are as shown in FIGS. 3 and 4, respectively.
Including Outgoing Resource Availability IG, Outgoing
Resource Availability IG includes a RAIG flag. Figure 3 shows the Outgoing Resource Availability IG
The details of the Outg of Uplinks IG (see Fig. 4) are also shown.
The oing Resource Availability IG has the same format as that shown in FIG. The RAIG flag indicates the type of traffic that can pass through the
The oing Resource Availability IG indicates the available bandwidth in the direction from the own node to the outside. The “in the direction from the own node to the outside” means, for example, that the Horizontal Links IG between A1 and A2 are generated at the nodes A1 and A2, respectively, and the data generated at A1 is A1 → A2 That is to say the direction. As shown in the fornat of FIG. 3, the RAIG flag includes 1-bit CBR, rt-VBR, nrt-VBR, ABR, and UB.
There are flags for each of R, CBR call, real-time VBR call, non-real-time VBR call, ABR call, U
In response to a BR call, setting these flags to ON indicates that a call of the corresponding traffic type can pass through the link.

The above-mentioned Horizontal Links IG and Uplinks
The IG is carried on PTSE, which is one unit of data managed by the topology database, and transmitted to another node. Actually, PTSE is PTSP (PNNI Topol
ogy State Packet: PNNI topology state packet)
And transmitted to other nodes. Here, the topology database is
A collection of PTSEs provided in a node and transmitted from other nodes by flooding.
FIG. 5A shows the format of PTSE, and FIG. 5B shows the format of PTSP.

Here, the flooding procedure will be described. First, each node stores data (Ho
rizontal Links IG, Uplinks IG, etc.) and put it on PTSE (actually using PTSP)
Send to all adjacent nodes in the group. PTS
The node receiving E stores it and transmits it to all adjacent nodes in the group. When receiving the data transmitted by itself, no further transmission is performed.
By repeating this for all nodes, data of all nodes is distributed to all nodes. This is also performed at a logical node (in a logical node, a representative node among a plurality of grouped nodes performs this). By the above operation, all the nodes have data on all the nodes (the logical nodes for the grouped nodes).

Next, with reference to FIG. 1, FIG. 6 and FIG. 7, the operation of the incoming call restriction in this embodiment will be described. FIG. 6 is a flowchart showing the operation of the incoming call restriction in this embodiment, particularly focusing on the processing in the RAIG flag control processing unit 15 (FIG. 1).

When a call control message is received from another exchange or terminal, it is determined whether or not the call control message is a call setup message, and whether or not a call is established (step 61). If the call is established upon receiving the call setup message, the number of calls of the corresponding traffic type of the link to which the call is established is counted up (step 62). Then, it is determined whether or not the number of calls after the count has reached a preset value (step 63). If it has not reached, the operation of the incoming call restriction is terminated without doing anything. As a result, a call of the designated traffic type is established on the designated link, and communication is started. On the other hand, in step 63, if the number of calls after the count-up has reached the value set in advance, the Horizontal Links IG and Uplinks IG of the corresponding link
Outgoing Resource Availability in IG RAIG in IG
Turn off the bit of the corresponding traffic type of the flag,
Flooding is performed by the flooding control processing unit 14 (FIG. 1) (step 64). As a result, the incoming traffic regulation of the traffic type is performed. Here, Horizontal Links IG and Uplinks IG
Although the operation of the AIG flag was performed, depending on the configuration of the network, the horizontal link
Only one of the horizontal link IG and the uplink IG may be operated. In this case, only the corresponding RAIG flag of the horizontal links IG and the uplink IG is operated, and
Only the corresponding one of Links IG and Uplinks IG is flooded.

If the call is not established in step 61, it is determined whether or not the call control message is a call release message (step 65). If it is not a call release, nothing is done, so that the state related to incoming call regulation does not change. If a call release message is received from another switch or terminal and the call is released, the number of calls of the relevant traffic type of the relevant link from which the call is released is counted down (step 66), and the number after the countdown is reduced. It is determined whether the value is less than a preset value (step 6).
7). If not, nothing is done, and the incoming call restriction state is maintained as it is. On the other hand, if the number after the countdown is less than the preset value,
O in the Horizontal Links IG and Uplinks IG of the link
The corresponding traffic bit of the RAIG flag in the utgoing Resource Availability IG is turned on, and the flooding is performed by the flooding control processing unit 14 (step 58). As a result, the incoming call restriction for the traffic type of the link is released.

Next, the reason why the incoming call can be restricted by the operation on the RAIG flag and the flooding will be described.

For example, in the network shown in FIG. 2B, the node A2 is connected to the Outgoin
g C in RAIG flag in Resource Availability IG
Turn on the BR bit, rt-VBR bit and ABR bit,
A2-A with nrt-VBR bit and UBR bit turned off
Suppose that Horizontal Links IG between three is generated and flooded. The terminal accommodated in the node A1 is the node A
When a UBR call in which the destination number of the terminal accommodated in No. 3 is specified is called, the node A1 performs a route search. As a result, the node A1 determines the node A3 from the called number, but the node A2
Since it is determined by the HorizontalLinks IG sent from the node A2 that the UBR call is not permitted between -A3, a route that does not pass through the link between A2-A3 is searched. In the illustrated example, since no other route is found, a call loss occurs at the node A1. Then, the node A2 turns on the UBR bit of the RAIG flag.
When the Horizontal Links IG between -A3 is generated and flooded, the UBR call can pass between A2 and A3.

That is, the RAI in the Horizontal Links IG
By turning off or on the bit for each traffic type in the G flag, it is possible to restrict or release the call of the corresponding traffic type in the corresponding link. In addition, since it is determined whether or not the traffic is regulated at the time of route creation, useless call control message transmission / reception is eliminated.

The same applies to the case of Uplink. Node A3 generates and floods Uplinks IG between A3 and B with the CBR bit in the RAIG flag turned off,
When the terminal accommodated in No. 1 issues a CBR call designating the called number of the terminal accommodated in the node B2, the fact that the CBR call is not permitted between A3 and B is Uplinks IG sent from the node A3. In this case as well, a route is not found and a call loss occurs at the node A1. Like Horizontal Links IG, RAI in Uplinks IG
By turning off or on the bit for each traffic type in the G flag, it is possible to restrict or release the call of the corresponding traffic type in the corresponding link.

Next, an example in which the incoming call restriction method of this embodiment is specifically applied will be described. FIG. 7 is a diagram showing a specific example of a network constituted by exchanges implementing the incoming call control method according to the present invention. The exchange 23 implementing the incoming call control method according to the present invention is connected to the exchange 22. The exchange 22 does not necessarily have to implement the incoming call control method according to the present invention, but may be based on a conventional incoming call control method. The signaling system between the exchanges 23 and 22 is a PNNI protocol.
A terminal 24 is connected to the exchange 23, and a terminal 21 is connected to the exchange 22.

In the initial state, the exchanges 23 and 2
It is assumed that the number of calls for each traffic type established on the link between 2 and 0 is all zero. Exchange 22 and Exchange 2
3 shall be able to support calls of all traffic types, and the RAs of the Horizontal Links IG of the links between them shall be
In the IG flag, it is assumed that all traffic type bits are on and flooded. Further, it is assumed that the number of incoming call restriction calls for each traffic type of this link in the exchange 23 is all one.

In this state, when terminal 21 transmits a CBR call setup message to terminal 24, exchange 22 receives this call setup message and transmits it to exchange 23.
The exchange 23 establishes a CBR call and at the same time
In the G flag control processing unit 15, the CBR of this link
Count up the number of calls. As a result, the number of CBR calls on this link has reached the number of incoming call restriction calls.
Outgoing Resource Availabilit in IG and Uplinks IG
y Turn off the CBR bit of the RAIG flag in the IG,
The flooding is performed by the flooding control processing unit 14. As a result, these HorizontalLinks IG and Up
The exchange 22 receiving the links IG sends the CBR
To determine that the call cannot be supported,
Even if the call setting message of another CBR call is transmitted to the terminal 24 while the CBR call established by 1 is established, the exchange 22 does not transmit the call setting message of another CBR call to the exchange 23.

After this, the CBR established by the terminal 21
When a call release message for releasing a call is transmitted to the exchange 22, the exchange 22 transmits the call release message to the exchange 23. The exchange 23 establishes the first established CBR.
At the same time that the call is released, the RAIG flag control processing unit 15
Counts down the number of CBR calls on that link. As a result, the number of CBR calls on the link is less than the number of incoming call restriction calls, so that the RAIG flag control processing unit 15 outputs
The CBR bit of the RAIG flag in the going Resource Availability IG is turned on, and the flooding control processing unit 14 performs flooding. This Horizontal L
The exchange 22 that has received the inks IG and the Uplinks IG determines that the link can support the CBR call, and therefore transmits a call setup message for the CBR call on the link to the exchange 23.
Can be sent to

[0034]

As described above, according to the present invention, the RAIG
Manipulate flags and use HorizontalLinks IG and Upli
By flooding nks IG, even if the number of calls of a certain traffic type on a certain link has already reached the number of calls of a predetermined traffic type, it is possible to prevent a decrease in processing capacity. effective. The reason is that, when the number of calls of the traffic type of the link has already reached the number of calls of the predetermined traffic type, the call setting message of the call of the traffic type of the link is transmitted from another exchange. Because it does not come.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an incoming call restriction device according to an embodiment of the incoming call restriction method of the present invention.

FIG. 2A is a diagram showing an example of a network configuration, and FIG.
Is a diagram illustrating a network configuration after grouping is performed, and (c) is a diagram illustrating a network configuration viewed from nodes A1 to A3.

FIG. 3 is a diagram illustrating a format of Horizontal Links IG.

FIG. 4 is a diagram illustrating a format of UpLinks IG.

FIGS. 5A and 5B are diagrams for explaining the format of PTSP and PTSE, respectively.

FIG. 6 is a flowchart showing an incoming call restriction process in the incoming call control device shown in FIG. 1;

FIG. 7 is a diagram illustrating a configuration example of a network.

FIG. 8 is a block diagram showing a configuration of hardware and software used for implementing a conventional incoming call restriction method.

FIG. 9 is a flowchart showing an operation of the conventional incoming call control method shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 PTSE transmission / reception part 2 Flood control processing part 3 RAIG flag control processing part 4 Call control processing part 5 Control part 6 Recording medium 7 Call control message transmission / reception part 20,23 Terminal 21,22 Switch

Claims (6)

[Claims] 1. A method for controlling incoming calls in a network according to a PNNI protocol, wherein when the number of calls of a certain traffic type on a link reaches a predetermined number for each traffic type, Outgoing for the link is performed. resource availability An incoming call restriction method for performing flooding by turning off the bit of the corresponding traffic type in the RAIG flag in the IG, thereby restricting the incoming call of the traffic type of the link. 2. A method for restricting incoming calls in a network according to a PNNI protocol, wherein the number of calls of a certain traffic type on a link has reached a predetermined number for each traffic type. Outgoing for the link when the number of calls falls below the predetermined number
resource availability An incoming call restriction method for turning on a bit of a corresponding traffic type in a RAIG flag in an IG to perform flooding, thereby releasing the incoming call restriction of the traffic of the link. 3. A terminating control device in a node provided in a network according to a PNNI protocol, wherein when the number of calls of a certain traffic type of a link belonging to the node reaches a predetermined number, the link is controlled. Outgoing resource availability RAI in IG
An incoming call restriction device comprising: a RAIG flag control processing unit that turns off a bit of a corresponding traffic type in a G flag; and a flooding control processing unit that performs flooding in accordance with the processing in the RAIG flag control processing unit. 4. A termination control device for a node provided in a network according to a PNNI protocol, wherein the number of calls of a certain traffic type on a link belonging to the node reaches a predetermined number for each traffic type. The number of calls of the traffic type falls below the predetermined number in the state where
An incoming call restriction device comprising: a RAIG flag control processing unit that turns on a bit of a corresponding traffic type in an AIG flag; and a flooding control processing unit that performs flooding in accordance with the processing in the RAIG flag control processing unit. 5. A computer-readable recording medium for controlling a node provided in a network according to a PNNI protocol, wherein the number of calls of a certain traffic type of a link belonging to the node is set to a predetermined number. If it reaches, the outgoing resource availability of the link
A recording medium storing a program for causing the computer to execute a function of turning off a bit of a corresponding traffic type in a G flag and a function of performing flooding. 6. A computer-readable recording medium for controlling a node provided in a network according to a PNNI protocol, wherein the number of calls of a certain traffic type on a link belonging to the node is previously determined for each traffic type. When the number of calls of the traffic type falls below the predetermined number in a state where the number has reached the predetermined number, R in the Outgoing resource availability IG for the link
A recording medium storing a program for causing the computer to execute a function of turning on a bit of a corresponding traffic type in an AIG flag and a function of performing flooding.