JPH05268254A - Call setting system in communication network - Google Patents

Abstract

PURPOSE:To quickly and efficiently process call setting processing separately from connection connecting processing by registering an incoming node signal to a route information table together with an output route number as route information and setting a direct pass between all the nodes managed by a maintenance center. CONSTITUTION:The system is provided with an exchange controller 2 managing the route information table 1 and a switch device 3 route-converting a cell of which route information is rewritten based on the content of the table 1. At the same time, the system is provided with the maintenance center 5 having a network constitution data base 4 registering the incoming node number and the output route number of each node separately from an incoming node to notify the incoming node number and the output route number to each node from the center 5. Each node receiving it registers the incoming node number to the route information table 1 so as to set the direct pass between all the nodes managed by the maintenance center 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication control system for separating call setting and connection setting in an ATM network.

[0002]

2. Description of the Related Art B-ISDN is a next-generation communication technology.
(Broad-band Integreated Service Digital Network) is under study, and ATM (Asynchronous Transfer Mode) is used as a communication exchange technology for realizing this B-ISDN.
Exchange technology is being considered. With this ATM exchange technology,
This is a technology to transfer data such as voice or image in fixed length packets called cells, and the conventional STM (Synchrono) that allocates a fixed band according to the amount of information.
It is expected to be a technology that enables the transfer processing of enormous amounts of data such as image information that is difficult to handle with the us Transfer Mode) method.

[0003]

However, the above-mentioned A
Also in the TM switching technology, call setup is performed by an existing method, that is, by sequentially linking a destination node (destination switching center) and a destination node (destination switching center) from a source node (source switching center) through a plurality of relay nodes (relay switching center). Then, a method of establishing a call and a connection by so-called link-by-link is considered.
Therefore, the communication speed after the connection is established is sufficiently high, but there is a problem that it takes a lot of processing time to establish the connection.

In addition, in the ATM network, since a large amount of information, so-called burst information, is instantaneously handled, it is necessary to appropriately select a path (a path with a large used bandwidth) that can minimize cell discard depending on the information content. It is expected that it will be necessary to select a route with a connection setting different from the call setting.

The present invention has been made in view of the above problems, and an object thereof is to provide a technique capable of realizing a high-speed call setup and a control system in which a call and a connection are separated. is there.

[0006]

According to the present invention, in a telecommunication switching network in which a unique node number is assigned to each node, information is stored in a cell to which route information is added and the information is transferred between the nodes, A route information table 1 for registering route information is provided in the switch, a switching control device 2 for managing the route information table 1, and a switch for performing route exchange of cells in which the route information is rewritten based on the contents of the route information table 1. A network configuration database 4 in which the device 3 is provided and the destination node number and the outgoing route number of each node are registered
A maintenance center 5 having a destination node number and an outgoing route number is provided from the maintenance center 5 to each node. As a result, the direct path is set between all the nodes managed by the maintenance center 5 by registering it in the route information table 1 together with the outgoing route number.

When a call setup request arrives from the originating terminal 6 connected to any one of the nodes (originating node 7), the node concerned arrives at the destination node through the direct path defined in the route information table 1. Call is set to 8.

[0008]

According to the present invention, as shown in FIG. 1 which is a principle diagram, when the cell of the call setup request arrives, the route information table 1 preset by the maintenance center 5
Based on the above, each node retransmits the call setup request to the next-stage node without considering the bandwidth and the like. in this way,
By setting the direct path between all the nodes, the call connection can be separated from the connection connection and processed at high speed and efficiently.

[0009]

(Embodiment 1) FIGS. 2 and 3 show a format of a cell 11 in ATM, and FIG. 2 shows a header portion of the cell 11 in a calling terminal 6 to a calling node 7. 3 shows the header portion of the cell 11 between the nodes.

The header 9 includes 4-bit flow control information (GFC: Generic Flow Control), 8-bit path information (VPI), and 12-bit channel information (VC).
I) and 3-bit cell format information (PT: Payload Typ)
e) and cell loss priority information (CLP: Cell Loss Priorit)
y), and 8-bit header control information (HEC: Heade
rError Control) and.

The latter includes flow control information (GFC).
The path information (VPI) is assigned instead of. Both of them have an information field 12 following the header.

In the cell 11, the path information (VPI) as the route information and the channel information (VCI) are sequentially rewritten for each node and transmitted, and finally reach the destination terminal 13 from the destination node 8.

FIG. 4 is a diagram conceptually showing the separation control of call setting and connection setting which is an embodiment of the present invention. As shown in the figure, a plurality of nodes 10, ... Are present between the originating terminal 6 and the terminating terminal 13, and the connection connection request is achieved by link-by-link for each node. The request realizes a direct path from the source node 7 to the destination node 8. Where "direct path"
In fact, even if a call connection request is made, each node 1
It means that the cell 11 of the call connection request is mechanically sent to the next node 10, ..., But does not execute any connection procedure such as bandwidth reservation at each node 10 ,. To do.

FIG. 5 is an overall view showing the network configuration of this embodiment. In the figure, a unique node number is given to each node, and these are collectively managed by the maintenance center 5.

FIG. 6 is a block diagram showing the configuration of the maintenance center 5 and the nodes. In the figure, the maintenance center 5 has a network configuration database 4 and a node management device 14.

The network configuration database 4 has a registration area for each node, and the destination node 8 and the corresponding outgoing route number are registered as a pair in this registration area. In FIG. 6, for example, in the node # 1, when the call connection request cell 11 whose destination node 8 is # 2 arrives, the cell 11 is instructed to output from the outgoing route "A". Is becoming

Each node is provided with a switching control device 2, a route information table 1, and a switch device 3.
The switching control device 2 has a function of controlling the rewriting of the route information table 1, and the cell 11 that arrives at the node concerned.
The header information is rewritten according to the contents of the route information table 1 to pass through the switch device 3.

The path information table 1 contains the path information (input VPI) and channel information (input VC) of the input cell 11.
I) is used as an index, and the physical outgoing line of the node, the path information (outgoing VPI) and the channel information (outgoing VCI) of the output cell 11 are respectively registered.

Although the route information table 1 is divided into a direct connection table 15 and a general user table 16, only the direct connection table 15 is used in this embodiment.

Here, regarding the route information for call connection used in this embodiment, the node number of the destination node 8 is directly registered as the channel information (VCI). In the figure, when the outgoing line is indicated by “¥”, the cell 11 itself is taken in as the destination node 8. Therefore, the cell 11 whose incoming VCI is shown as "00001" in the figure indicates that the cell (# 1) itself should take in the cell 11.

"*" Means don't care, that is, the corresponding information in the cell 11 is ignored.
In the figure, the cell 11 whose incoming VCI is "00002"
Indicates that the outgoing line is "0" regardless of the values of incoming VPI and outgoing VPI.
000A ", and the input VCI is output as it is as the output VCI.

As described above, as for the channel information (VCI) for direct connection, the outgoing line can be determined only by the channel information (VCI) regardless of the value of the path information (VPI). Moreover, since this channel information (VCI) is a unique value indicating each node in the entire network,
In each node, when the cell 11 having the same channel information (VCI) as its own node number arrives, the node becomes the destination node 8 and therefore the cell 11 is fetched. Also, channel information (V
When the cell 11 having the CI) arrives, the channel information (VCI) is directly rewritten to the node of the next stage determined by the route information table 1 without rewriting.
Send 1.

In this embodiment, the contents of the network configuration database 4 of the maintenance center 5 are notified to the exchange control unit 2 of each node through the node management unit 14 in order to set the direct path between all the nodes.

Upon receipt of the notification, the switching control device 2 of each node converts the node number into an input VCI and an output VCI, further converts the output route number into a physical output line number, and routes them. It is registered in the direct connection table 15 of the information table 1.

As described above, by writing the route information collectively managed by the network configuration database 4 in the route information table 1 of each node, a direct path is realized between all nodes, and one of the originating nodes 7 It is conceptually possible to directly make a call connection request to any destination node 8.

FIG. 4 shows an example in which a direct path is set between the Kawasaki station, which is the source node 7, and the Aizu station, which is the destination node 8. However, since this direct path does not consider the bandwidth and the like at all, it can be used only for call setup, but as far as call setup is concerned, it is possible to perform extremely high-speed and efficient processing as compared with the prior art.

Further, regarding connection connection, linking is performed while securing bandwidth between each node as in the prior art.
It is done by a bi-link system. Therefore, in the case of a connection connection request, the route information table 1 is rewritten for each node while a band is secured with the next-stage node, and a link-by-link connection is performed.

In FIG. 4, connection connection is realized while establishing links in the order of Kawasaki station → Tokyo station → Fukushima station → Aizu station. As described above, in this embodiment, the call setup procedure and the connection connection procedure are separated, and the call setup procedure is performed through the direct path set between all the nodes.
The call setup process can be performed at high speed.

(Second Embodiment) In the first embodiment, the direct connection table 15 is collectively managed by the maintenance center 5, but in the second embodiment, each node autonomously communicates with another node. This is the case when setting a direct path with.

FIG. 9 shows a direct path setting method using a general call setting procedure in the prior art. Each node has a switching control device 2, and in this switching control device 2, all node numbers and the next node 10
It has a logical node database 17 in which a signal transmission destination (outgoing route) is registered. In addition to the above, a call connection analysis table 18 and a connection connection analysis table 20 as shown in FIG. 8 are provided, and these tables will be described later.

The structure of the route information table 1 is the same as in the first embodiment.
And is composed of a direct connection table 15 and a general user table 16. Further, the switch device 3 has the same configuration.

A procedure for setting a direct path between nodes will be described with reference to FIG. First, originating node 7
(# 1) stores the partner node number in the IAM signal which is the direct path setting request and transmits it to all the nodes.

In the next node 10 (# 2), if the node number stored in the IAM signal which is the signal of this direct path setting request is compared with the node number given to itself, and if they match, the node itself is It becomes the destination node 8, determines the VPI and VCI with the preceding node (# 1), stores this in the ACM signal which is a direct path setting completion notification, and returns it to the originating node 7 (# 1). The originating node 7 (# 1) rewrites its own routing information table 1 (# 1) based on the VPI and VCI stored in the ACM signal.

On the other hand, in the next node 10 (# 2), when the direct path setting request signal (IAM signal) received from the source node 7 (# 1) is not for itself (does not match its own node number), Previous node 7 (#
The VPI and VCI with 1) are supplemented, and the direct path setting request signal (IAM signal) is retransmitted to the node 8 (# 3) at the next stage.

When the next-stage node 8 (# 3) is the destination node 8, the VPI and the VPI stored in the direct path setting completion notification (ACM signal) received from the destination node 8 (# 3) VCI out VPI and out VCI
, The VPI and VCI with the preceding node 10 (# 1) are registered in the incoming VPI and incoming VCI, and the route information table 1
To complete the rewriting.

Further, the relay node 10 (# 2) sends a direct path setting completion notice (ACM signal) to the preceding node 7 (# 1) using the VPI and VCI between the preceding nodes as parameters. The node 7 (# 1) at the preceding stage that has received this rewrites its own route information table 1 (# 1) based on the VPI and VCI stored in the ACM signal. As described above, the source node 7 (#
A direct path between 1) → relay node 10 (# 2) → destination node 8 (# 3) is set.

As described above, in the second embodiment, since the direct path is set between all the nodes by using the normal call setup procedure, it is not necessary to add any complicated hardware.
Once the direct path is set, it is not necessary to set it again except when the node configuration is changed.

FIG. 7 is a processing flow of a call setting or connection connection request in each node after the direct path is set as described above. In the figure, in the case of call setup, each node transmits the cell 11 from the source node 7 to the destination node 8 through the direct path set up above without any processing in the relay node 10. On the other hand, in the case of a connection connection request, the cell 1 from the source node 7 to the destination node 8 is linked by link while determining the VPI and VCI for each node.
1 is transmitted.

In the figure, when a node receives a signal, it is first judged whether or not this is a setup signal (step 101). Here, in the case of the setup signal, the node is the source node 7,
The calling service is analyzed (102). The subsequent processing of the calling node 7 is call connection request processing (103 to 105).
And connection connection request processing (106 to 108) are performed in parallel.

In the call connection request processing flow, the destination node 8 is first analyzed (103). This destination node 8
The analysis is performed by referring to the call connection analysis table 18 in the switching control device 2, the final node number (ID) is determined by the telephone number from the calling terminal 6, and this destination node number is set to VCI. .. Then, the call connection request is sent from the calling node 7 (104). This call connection request is directly transmitted to the destination node 8 via each relay node 10 by the direct path set above.

When the destination node 8 receives the call connection request, it sends it to the receiving terminal 13, and when the receiving terminal 13 gives a call setup completion notice, it returns it to the originating node 7 through the direct path (105).

In the connection connection request processing flow, the next node 10 is analyzed based on the connection connection analysis table 20 (106). A connection connection request is sent to the next node 10 determined as a result (107). In the next node 10, the VPI and VCI that secure the necessary bandwidth for the connection connection request
Is notified to the originating node 7. As a result, the link between the source node 7 and the next-stage node 10 is achieved. Thus, when the link of the connection connection request between the source node 7 and the destination node 8 is completed while the links of the relay nodes 10 are sequentially realized, the destination node 8
A connection connection request completion notification is sent to (1
08).

The originating node 7 first receives the call connection completion notification from the destination node 8 (105), and further upon receiving the connection connection completion notification (108), sequentially notifies the originating terminal 6 of these (109). , 110).

As described above, when the node is the originating node 7, the call connection request and the connection connection request are made in parallel. Next, when the received notification is not the setup signal, that is, when the notification is not from the calling terminal 6 but from another node, it is determined whether the notification is a call connection request (111).

Here, since the call connection request is directly transmitted to the destination node 8 through the direct path as described above, when each node determines that the notification is a call connection request, that node receives the destination node 8. Only if

Therefore, the processing of steps 111 to 117 shows the call connection request processing in the destination node 8.
The destination node 8 first analyzes the incoming service and then waits for an incoming connection connection request following the call connection request (113).

When this connection connection request arrives,
The VPI and VCI with the preceding node are determined and a link with the preceding node is established (114). At this time, it is necessary to analyze the connection connection request and secure VPI and VCI that can secure a band larger than the request.

Next, a setup signal is sent to the receiving terminal 13 (115), and when this setup processing is completed, a call connection completion notification is sent to the calling node 7 through the direct path, and link-by The connection completion notification is sent to the node preceding the connection connection established by the link.

Next, in step 111, when the notification received by the node is not a call connection request, a connection connection request, that is, the node concerned is the relay node 10
Is the case.

Therefore, step 121 described below
The processes from 125 to 125 are the processes in the relay node 10. The relay node 10 first analyzes the next-stage node (121). This is performed by referring to the connection connection analysis table 20 provided in the switching control device 2 of each node.

Next, the band between the relay node 10 and the preceding node is secured and the VPI and VCI are determined (122). In this way, when the connection connection request from the preceding node is received (123), the step 1
A connection connection completion notice is sent through the link with the preceding stage established in 22 (124). When a connection connection completion notification from the next stage is received (12
5), the connection connection request processing in the relay node 10 is completed.

[0052]

According to the present invention, the call setup process can be separated from the connection connection process and can be performed quickly and efficiently through the direct path without considering the bandwidth and the like.

[Brief description of drawings]

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

FIG. 2 is an explanatory diagram showing a cell format in ATM.

FIG. 3 is an explanatory diagram showing a cell format in ATM.

FIG. 4 is a diagram conceptually showing separation control between call setting and connection setting in the present invention.

FIG. 5 is an overall view showing a network configuration of the present invention

FIG. 6 is a block diagram showing a configuration of a maintenance center and nodes according to the first embodiment.

FIG. 7: Process flow of call setup or connection connection request in each node

FIG. 8 is an explanatory diagram showing a call connection analysis table and a connection connection analysis table.

FIG. 9 is a block diagram showing the configuration of each node in the second embodiment.

[Explanation of symbols]

 1 ... Route information table 2 ... Switching control device 3 ... Switch device 4 ... Network configuration database 5 ... Maintenance center 6 ... Originating terminal 7 ... Originating node 8 ... Destination node 9 ... Header 10 ... Relay node 11 ... ATM cell 12 ... Information field 13 ... Receiving terminal 14 ... Node management device 15 ... Direct connection table 16 ... General user table 17 ... Logical node database 18 ... Call connection analysis table 20 ... Connection connection analysis table

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H04Q 3/495 9076-5K

Claims (6)

[Claims] 1. A communication switching network in which each node is given a unique node number, information is stored in a cell to which route information is added, and the information is transferred between the nodes, and route information is registered for each node and the route information is registered. Route information table (1), exchange control device (2) managing the route information table (1), and route information table (1)
A maintenance center having a switch device (3) for exchanging a route of a cell whose route information is rewritten based on the contents of the above, and a network configuration database (4) in which a destination node number and an outgoing route number are registered for each node ( 5), the maintenance center (5) notifies each node of the destination node number and the destination route number, and each node receiving the notification outputs the destination node number as the route information. By registering together with the route number in the route information table (1), a direct path has been set between all the nodes managed by the maintenance center (5), and the direct path has been connected to any one of the nodes (source node). When the cell of the call setup request arrives from the calling terminal (6), the node concerned sends the call to the destination node through the direct path defined in the route information table (1). Call setup scheme in a communication network, characterized in that to set. 2. The calling node analyzes the cell of the call setup request to determine the called node, and writes the called node number in the route information of the call setup request cell.
Call setup method in the described communication network. 3. The calling node according to claim 1, wherein the calling node sends a connection connection request to the next node in parallel with the process of sending a call setup request to the called node through the direct path. Call setup method in a communication network. 4. A communication switching network in which each node is given a unique node number, information is stored in a cell to which route information is added, and information is transferred between the nodes, and route information is registered for each node and the route information is registered. Route information table (1), exchange control device (2) managing this route information table (1), and said route information table (1)
Has a switch device (3) for exchanging the route of the cell whose route information has been rewritten based on the contents of the above, and each node sends a direct path setting request to all the other nodes to the next stage node, The next-stage node takes in the direct-path setting request when it is a direct-path setting request for itself, and when it is not a direct-path setting request for itself, retransmits the direct-path setting request to the next-stage node, The node that takes in the setting request returns a path setting completion notification to the node that has sent the direct path setting request with the path information (VPI) and the channel information (VCI) as parameters, and receives the direct path setting notification. The source node of the request uses its own route based on the above parameters. By rewriting the report table 1, a direct path is set between all the nodes, and when a cell of the call setting request arrives from the calling terminal (6) connected to one of the nodes (calling node), A call setup method in a communication network, wherein the node sets up a call with respect to a destination node through a direct path defined in the route information table (1). 5. The calling node (7) analyzes a cell of a call setup request to determine a destination node (8) and writes the destination node number in the route information of the call setup request cell. A call setup method in the communication network according to claim 4. 6. The originating node 7 makes a connection connection request to the next node (10) in parallel with the process of making a call setup request to the destination node (8) through the direct path. A call setup method in a communication network according to claim 4.