JPH06164577A - Communicating system - Google Patents

Abstract

PURPOSE:To effectively utilize a resource for controlling a switch device, and to simplify the control of routing, and to optimally arrange software. CONSTITUTION:Call controllers CCS-1,2 and connection controllers BCCS-1 to 3 for controlling the switch devices SW1 to 3 are separated from each other. In the call controllers CCS-1,2, the service control of mutual communication, etc., between terminals is executed by executing call state management and the transmission and the reception of a call control message. In the connection controllers BCCS-1 to 3, the setting or the release of channel connection is executed by controlling the switch devices SW1 to 3, and besides, the relation of bus connection and equipment to terminate that bus is managed. Then, the using state of a channel link and the usable communication resource contained in the bus connection to be terminated are managed by the switch devices SW1 to 3, and the setting route of the channel connection is determined.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is used for communication connection between terminals via a switch device. In particular, it relates to call control and connection control via a switch device.

[0002]

2. Description of the Related Art In a conventional N-ISDN communication network, a call indicating a logical relationship between users and a connection for transferring user information have a one-to-one correspondence, and the call and the connection are set. And the release was taking place at the same time.

On the other hand, in recent years, there has been an increasing demand for multi-party communication having a plurality of communication partners such as broadcast communication, and multi-connection communication combining a plurality of media such as voice, images and the like. In such communication,
There is a one-to-many relationship between calls and connections, and functions such as adding connections during communication are required.
The call and connection may not be set and released at the same time.

In response to such a situation, CCITT (International Telegraph and Telephone Consultative Committee) and the like are studying to separate the call control protocol and the connection control protocol. However, even in these studies, the applications above the call control protocol and the connection protocol are considered as an integrated device.

[0005]

When the call control unit and the connection control unit are not separated as an integrated call processing device, for example, a plurality of terminals accommodated in one switch device request different services. Then, the following problems occur.

First of all, when the service provided by the call control unit is different for each call control unit, if the call control unit and the connection control unit are configured as an integrated call processing device, a terminal accommodated in the switch device is provided. Will belong to another call control device according to the requested service, and one switch device will be controlled by the connection control units of a plurality of call processing devices. Therefore, if a resource such as a channel link or a band that is terminated in the switch device is divided and assigned to each call processing device (connection control unit) to be controlled, a problem of division loss occurs. Further, since there are a plurality of call control devices (connection control units) that control one switch device, a call control device (connection control unit) that controls the channel connection when setting a channel connection passing through the switch device. Selection logic (routing control) is complicated.

Secondly, in order to avoid the above problems, when controlling a switch device accommodating a terminal by one call processing device, it is necessary to install all the service control software in the call processing device. , Duplicated implementation of software causes cost increase and other problems.

The present invention solves such a problem, enables effective use of resources, simplifies routing control,
It is an object of the present invention to provide a communication system in which call control and connection control are separated so as to enable optimum placement of software.

[0009]

The communication system of the present invention comprises:
It is characterized in that call control and connection control are separated. That is, a switch that forms a channel connection by terminating one or more path connections each including a plurality of channel links capable of transmitting information, and connecting the channel links included in the path connections between the terminated path connections. Control means for controlling the formation of a channel connection in each of the plurality of switch devices, the device being provided with a plurality of devices, the switch devices being mutually connected and the individual switch devices and the terminals accommodated therein being connected by a path connection. In the communication system, the control means includes a call control device that receives a request from a terminal and performs service control including mutual communication between the terminals, and a channel connection for information transfer between the terminals under the control of the call control device. Connection control device to set or release Separately included, the call control device is provided with a means for managing the call state and a means for transmitting / receiving a call control message, and the connection control device controls the switch device to set or release the channel connection. A means for performing, a means for managing the relationship between the path connection and a device terminating the path connection, the usage status of channel links included in the path connection terminated by the switch device, and available communication resources (hereinafter referred to as "resource"). And a routing means for determining a setting route of the channel connection.

In the present specification, "including the connection control device and the call control device separately" is not limited to those physically provided separately, but in the case of being separated by software. including.

The call control device and the connection control device are connected by a channel connection, and the call control device sets a channel connection for information transfer between terminals via control of the connection control device by message communication on the channel connection. It is preferable that the communication service between terminals is realized.

In this case, the call control device performs control for releasing the channel link and the band and other resources at least at the end point on the switch device side of the channel link between the terminal and the switch device to which this terminal is connected by the path connection. A means for instructing the connection control device, a control for securing a channel link, a band and other resources for a channel connection across the switching device to make a reservation state, a control for making a connection state in which information can be transferred from the reservation state, a reservation state Means for instructing the connection control device to perform control for releasing the resources of the above, or control in which these controls are combined, and information from one end point of a plurality of end points of the channel link terminated by one switch device to another end point. Or distributed to multiple endpoints, or 1 or Controls that reserve resources for a connection that multiplexes information from a number of end points into one end point and puts it in a reserved state, controls that a connection state in which information can be transferred from the reserved state, and stops information transfer from a connected state And a means for instructing the connection control device to perform control for setting a reserved state, control for releasing resources in the reserved state, or control that combines these controls, and uses these means to establish a channel connection for information transfer between terminals. It is preferable that it is configured and released.

[0013]

A call controller and a connection controller are connected using a channel connection, and the call controller controls the connection controller by message communication on this channel connection to establish a channel connection for information transfer between terminals. Set and realize communication between terminals. As a result, it is possible to optimally arrange the call control device and the connection control device, facilitating resource management and simplifying routing control, as compared with the case where the call control device and the connection control device are integrated. It is possible to reduce the amount of software installed.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

1. Device Configuration FIG. 1 is a block diagram showing an embodiment of the present invention.
An example in which the present invention is implemented in an M (asynchronous transfer mode) communication system will be shown.

When ATM is used, the path connection corresponds to a VP (virtual path) connection, the channel link corresponds to a VC (virtual call) link,
The channel connection corresponds to the VC connection.
That is, in this embodiment, one or more VP connections (VPC-1 to 4) each including a plurality of VC links (VCL-1 to 6) capable of transmitting information are terminated, and the VPs are terminated between the terminated VP connections. The switch devices SW-1 to 3 that form a VC connection by connecting the VC links included in the connection are provided, and the switch devices SW-1 to 3 are connected to each other and the individual switch devices SW-1 and 3 and the switch devices SW-1 and SW3. The terminals T-1 and T-2 housed therein are connected by VP connections VPC-1 to VPC-4, and a control means for controlling formation of a VC connection in each of the plurality of switch devices SW-1 to SW-3 is provided.

The feature of this embodiment is that the control means receives a request from the terminals T-1 and T-2 and performs a service control including mutual communication between the terminals.
A connection control device BCCS-1 for setting or releasing a VC connection for information transfer between the terminals T-1, 2 under the control of the call control devices CCS-1, 2.
3 to 3 are included separately. Call control device CCS-
1 and 2 are provided with a means for managing a call state and a means for transmitting and receiving a call control message. The connection control devices BCCS-1 to 3 are provided with switch devices SW-1 to 3 respectively.
Means for controlling or setting the VC connection and releasing the connection, means for managing the relationship between the VP connection and the device terminating the VP connection, and the switch device S.
V included in the VP connection terminated by W-1 to W-3
Means are provided for managing the usage status of the C-link and available communication resources, and routing means for determining the setting route of the VCVC connection.

1.1 Operation of Each Unit The switch devices SW-1 to SW-3 can secure and release switch resources for mutually connecting VC links terminating in the devices, or can transfer information between VC links. The connection processing and the disconnection processing for ending the information transfer are performed, and by this processing, the VC connection is set and released. In addition, the switch devices SW-1 to SW-3
Also performs processing for connecting between VP connections.

Connection control devices BCC-1 to BCC
S-3 is a control of the connection between the VC links terminated in the switch device by controlling the switch device,
It manages the relationship between the VP connection and the device that terminates the VP connection, manages the VC links contained in the VP connection, manages the usable bandwidth, etc., and determines the route of the VC connection using the management function described above. , VC connection determination and release.

In order to control the communication service of the terminals, the call control devices CCS-1 and CCS-2 transmit / receive call control messages related to communication service control and call state management between them. It also controls the connection control device in order to create and release a VC connection for information transfer of the terminal.

1.2 Connection Relationship Between Devices The terminals and the switch devices and the switch devices are connected by VP connections that accommodate a plurality of VC links therein. In the example of FIG. 1, the terminal T-1 and the switch device SW-1 are VC links VCL-1 to VCL-3.
Are connected by a VP connection VPC-1, and a VC link VCL- is connected between the switch devices SW-1 and SW-2.
Connected by VP connection VPC-2 that accommodates 4,
The devices SW-2 and SW-3 are connected by a VP connection VPC-3 that accommodates a VC link VCL-5, and the switch device SW-3 and the terminal T-2 are VC links VCL-6.
Are connected by a VP connection VPC-4.

The respective control connections between the terminal and the call control device, between the call control devices, between the call control device and the connection control device, between the connection control devices and between the connection control device and the switch device are , V
It is realized by setting a VC connection formed by connecting C links and further setting a connection of a higher layer protocol such as layer 2 or layer 3 on the VC connection. When a plurality of devices are realized by the same CPU (central processing unit), the control connection between the devices may be realized by using a message box provided by the CPU. The connection relationship between the devices is as follows.

The terminal T-1 and the call control device CCS-1 and the terminal T-2 and the call control device CCS-2 are connected by control connections T-CC-1 and T-TC-2, respectively. The call control device CCS-1 controls the communication service of the terminal T-1, and the call control device CCS-2 controls the communication service of the terminal T-2.

The call control devices CCS-1 and CCS-2 are connected by a control connection CC-CC-1, and a call control message relating to control of communication service between terminals is transmitted / received via the control connection CC-CC-1. I do.

Control connections CC-BCC-1 and CC-BCC- are provided between the call control device CCS-1 and the connection control device BCCS-1, and between the call control device CCS-2 and the connection control device BCCS-3, respectively. 2 and their control connections CC-BCC-1, C
Call control devices CCS-1, CCS via C-BCC-2
-2 is the connection control device BCCS-1,
The BCCS-3 is instructed to control the connection, and the VC connection for information transfer between terminals is generated and released. The connection control includes control of each of the terminal accommodating connection, the intra-switch device connection, and the inter-switch device connection.

Connection control devices BCCS-1, BC
Control connections BCS-BCC-2 and BCC-B are provided between CS-2 and between BCCS-2 and BCCS-3, respectively.
They are connected by CC-2, and control the connection between switch devices in relation to each other.

Between the connection control device BCCS-1 and the switch device SW-1, the connection control device BCC
Control connections BCCS-SW-1 and B are provided between S-2 and the switch device SW-2 and between the connection control device BCCS-3 and the switch device SW-3, respectively.
CCS-SW-2 and BCCS-SW-3 are connected, and the connection control devices BCCS-1 to BCCS-3 control the connection between VC links by the switch devices SW-1 to SW-3, respectively.

As described above, by connecting the devices by the VC connection or the control connection using the message box, it is possible to arrange a plurality of devices on the same CPU or on different CPUs. Optimum placement of equipment and software is possible.

In this embodiment, one call control device controls one connection control device, and one connection control device controls one switch device. However, one call control device is plural. Controlling one connection control device, one connection control device controlling a plurality of switching devices, one connection control device controlling a plurality of call control devices, or one switching device controlling a plurality of connections The present invention can be implemented in the same manner even if it is controlled by the device.

1.3 Connection Control Instructed by the Call Control Device to the Connection Control Device As shown in FIG. 1, the terminal T-1 and the terminal T-2 are in communication with each other for information transfer set at that time. VC connection of the VC link VCL-1 between the terminal T-1 and the switch device SW-1 and the switch devices SW-1 and SW-
VC link VCL-4 between two, switch device SW-2,
VC link VCL-5 between SW-3 and VC link VCL-6 between switch device SW-3 and terminal T-2.
Are concatenated. At this time, of the VC connections, the switch device that can be controlled by the call control device via the connection control device (in this case, SW-1
And SW-3) and the connection portion between the terminal (in this case, the VC link VCL-2 or VCL-6 connection portion) is referred to as "terminal accommodation connection".
, And the connection portion set between the switch devices that the call control device can control via the connection control device (in this case, the connection connecting the VC links VCL-4 and VCL-5) is referred to as "inter-switch device". A "connection", which is a connection between switch devices that is terminated between switch devices controlled by the call control device via the connection control device, or a connection part that connects end points of a terminal accommodating connection (connection part CON shown in FIG. 1). -1, CON-2) is referred to as "connection in switch device".

The call control device ensures control of resources such as VC links and bands related to the terminal on the switch device side of the terminal accommodating connection (hereinafter referred to as "terminal accommodating connection endpoint") via the connection controller (hereinafter referred to as "terminal"). The generation of the accommodation connection end point ") and the control of releasing the secured resource (hereinafter referred to as" release ") are performed. Further, regarding the inter-switch device connection and the intra-switch device connection, control is performed to secure resources such as VC links and bandwidths to a reserved state (hereinafter referred to as “connection generation”), and a connection state in which information can be transferred from the reserved state Control (hereinafter referred to as "connection"),
Performs control from the connected state to the reserved state (hereinafter referred to as "disconnect"), control to release resources in the reserved state (hereinafter referred to as "release"), or control of generation / connection / disconnection / release that combines these controls. .

Here, it is assumed that each device is provided with an identifier that can be uniquely identified within the communication network.

The VP connection can be uniquely identified in the communication network by combining the identifiers of the switch devices or terminals at both ends terminating the VP connection and the numbers capable of uniquely identifying the VP connection between the both end devices. is there.
The numbers that can be identified between the devices at both ends are "VP connection numbers", and the numbers that can be uniquely identified in the communication network are "V".
P connection identifier ”. Also, the VC link is
Identifier of the VP connection accommodating it and the VP
The VC link in the connection can be uniquely identified in the communication network by combination with the uniquely identifiable number. The number of the VC link that can be identified in the VP connection is called "VC link number", and the number that can be identified in the communication network is called "VC link identifier".

By using these identifiers, it is possible to represent the end point of the connection terminated by the switch or the terminal. FIG. 2 shows an example of the structure of an identifier representing an endpoint, that is, an endpoint identifier. The endpoint identifier is composed of a device identifier accommodating the endpoint, an identifier of the other device terminating the VP connection including the endpoint, that is, an adjacent device identifier, a VP connection number, and a VC link number. A combination of the device identifier, the adjacent device identifier, and the VP connection number becomes the VP connection identifier, and a combination of the VC link number and the VC link identifier becomes the VC link identifier. For example, in the case of the end point on the switch device SW-1 side of the VC link VCL-1 in the configuration example shown in FIG. 1, the switch SW1 identifier is the device identifier, the terminal T-1 identifier is the adjacent device identifier, and the VP connection is the VP connection. The number of the VP connection VC-1 is inserted as the number, and the number of the VC link VCL-1 is inserted as the VC link number.

Hereinafter, control of the terminal accommodation connection end point,
An overall control flow of control between connections between switch devices, control of connections within switch devices, and terminal-to-terminal communication performed using these connection controls will be described.

2. Control of terminal accommodating connection A process in the case where the call control device requests the connection control device to generate and release the terminal accommodating connection end point will be described.

2.1 Attribute information regarding terminal accommodating connection In order to represent each terminal accommodating connection, three attribute information of (1) terminal accommodating connection identifier, (2) terminal accommodating connection endpoint identifier, and (3) bearer information are used. To be

The terminal accommodating connection identifier is information for uniquely identifying the terminal accommodating connection among the devices, and is uniquely at least among the terminals, call control devices and connection control devices related to the control of the terminal accommodating connection. Must be identifiable. However, the identifiers may be changed between the terminal and the call control device and between the call control device and the connection control device. In that case, the call control device manages the correspondence of the identifiers.

The terminal accommodating connection end point identifier is information for identifying the end point of the terminal accommodating connection on the switching device side, and basically has the configuration shown in FIG. That is, it includes a switch device identifier, a terminal identifier, a VP connection number, and a VC link number. When handling a bidirectional connection with one terminal accommodation connection end point identification information, two VP connection numbers and two VC connection numbers are prepared for each direction.

The bearer information is information on the band, quality, etc. allocated to the terminal accommodation connection.

2.2 Generation of terminal accommodating connection end point The call control device specifies a terminal accommodating connection identifier, a terminal accommodating connection end point identifier and bearer information,
Request the connection control device to generate a terminal accommodation connection end point. The request-destination connection control device selects a VC link that can be used within the range specified by the terminal accommodation connection end point identifier, performs processing to secure resources such as the VC link and band, and requests the result to request-source call control. Return to the device. When the resources such as the VC link and the band can be secured, the VC link identifier secured is notified together with the result (success). If there are no resources such as VC links or bandwidth that can be used, a result (failure) is returned.

In this control, the request source call control device is
As the terminal-accommodating connection endpoint identifier, three levels of specification by the identifier of the terminal accommodating the terminal of the terminal-accommodating connection or the identifier of the switch device, specification by the VP connection identifier, and specification by the VC link identifier are allowed. At this time, the request destination connection control device selects a usable VC link from the range specified at each level, and when it is able to secure it, it notifies the request source control device of the secured VC link identifier. When selecting a VC link, the VC link may be in use if the endpoint is specified by the VC link identifier.

Further, in this control, the requesting call control device needs to specify at least the terminal identifier among the terminal accommodation connection end point identifiers. Since the request destination connection control device manages the device that terminates the VP connection, the switch device and the VP connection under the control of the request destination connection control device that accommodates the terminal can be specified from the designated terminal identifier.

2.3 Release of terminal accommodating connection end point When the call control device specifies the already generated terminal accommodating connection identifier to the connection control device and requests the release of the terminal accommodating connection terminal, the request destination connection control device is specified. Further, processing is performed to release resources such as VC link and band allocated to the end point of the terminal accommodating connection, and the result is notified to the call control device. At this time, if the VC link to be released is shared with the connection in the switch device that has already been created,
The connection control device manages the VC link as a usage state.

3. Control of connection between switch devices Here, on the premise of the configuration shown in FIG. 1, control of generation / connection for simultaneously generating and connecting the connection between switch devices terminated by the switch devices SW-1 and SW-3. Regarding disconnection / release control for simultaneously performing disconnection and release, the call control device CCS-1 of the request source, the connection control device BCCS-1 of the request destination, and the switch device SW-2 that relays the connection between the switch devices. The respective processing contents of the connection control device BCCS-2 for controlling the switch and the connection control device BCCS-3 for controlling the switch device SW-3 that accommodates the other end of the inter-switch device connection will be described.

3.1 Attribute Information Regarding Connection Between Switch Devices Before describing the sequence of processing contents, the attribute information for representing each connection between switch devices will be described.

The attribute information of the switch device connection includes (1) switch device connection identifier,
(2) Switch end point identifier between switch devices, (3)
Information on connection end point accommodation position between switch devices, (4)
The bearer information and (5) link identifier are used.
(1) to (4) are used between a request source control device (for example, CCS-1) and a request destination connection control device (for example, BCCS-1) for connection control between switch devices, and (1) to (5) Is a connection control device (eg, BC) that executes the process of connection control between switch devices.
It is used between CS-1 to BCCS-3).

The inter-switch-apparatus connection identifier is information for identifying the inter-switch-apparatus connection between the apparatuses, and at least call control apparatuses CCS-1, CCS-2 and connection control for controlling both end points of the inter-switch apparatus connection. Devices BCCS-1, BCCS-3
The condition is that the connection between the switch devices can be uniquely identified between the two.

The inter-switch device connection end point identifier is information for identifying both end points of the inter-switch device connection, and can be uniquely identified in the communication network. This information is based on the end point identifier shown in FIG. 2 when one end point is called a home and the other end point is called a mate.
The home side and mate side are combined. In the case of handling a bidirectional connection with one switch device connection end point identifier, the VP connection number and V
Prepare two C connection numbers and two for each direction.

The inter-switch device connection end point accommodating position information is information that gives the accommodating position of the end point of the inter-switch device connection by a different expression from the inter-switch device connection end point identifier, and the end point of the inter-switch device connection is the switch device. It is represented by the identifier of another end point connected by an internal connection. For example, switch device SW
In the case of the inter-switch device connection between -1 and SW-3, the inter-switch device connection end point accommodating position information is the switch device SW-1 side end point of the terminal accommodating connection with the terminal T-1 or the terminal. An identifier corresponding to the end point on the switch device SW-3 side of the terminal accommodation connection with T-2 is used.

The bearer information is information on the bandwidth, quality, etc. allocated to the terminal accommodating connection.

The link identifier is information for identifying a VC link which is a component forming a connection between switch devices, and is used to identify a VC link secured between the connection control devices in relation to the connection between switch devices. To do. The structure of this information is based on the structure shown in FIG.

3.2 Generation / Connection of Switch Device Connection FIG. 3 shows a flow of control of generation / connection of switch device connection.

In order to generate and connect a connection between switch devices, the call control device CCS-1 sends a connection control device BCCS-1 a connection identifier between switches, information on both end accommodation positions of the connection between switch devices, and between switch devices. Create connection between switch devices by specifying connection end point identifier and bearer information.
The connection request 3-1 is made. As the inter-switch connection identifier, for example, the identifier of the call control device CCS-1,
It is composed of a unique number in the call control device CCS-1.

Upon receiving the request 3-1, the connection control device BCCS-1 determines the route of the inter-switch device connection from the specified inter-switch device connection end point accommodation position information or inter-switch device connection end point identifier. In the case of this example, the route of the switch device SW-2 connected to the switch device SW-1 by the VP connection is selected. At this time, the end point on the switch device SW-1 side becomes one end point of the inter-switch device connection. Connection control device BCCS-1
Also secures resources such as a usable VC link and band from the VP connection between the switch devices SW-1 and SW-2, and connects the switch device to the connection control device BCCS-2 that controls the switch device SW-2. The identifier, the inter-switch device connection end point accommodation position information, the inter-switch device connection end point identifier, the bearer information, and the VC link identifier (link identifier) between the switch devices SW-1 and SW-2 secured by the connection control device BCCS-1. Designate and perform connection generation / connection request 3-2.

When the connection control device BCCS-2 receives this request 3-2, the connection control device BCCS
Switch devices SW-1 and SW- notified from CS-1
A resource such as a VC link and a band between the two is secured, and a route of the inter-switch device connection from the inter-switch device connection end point accommodation position information or the inter-switch device connection end point identifier, in this example, the switch device SW-2 and the VP connection. The route of the connected switch device SW-3 is determined, and the switch device SW-
VC that can be used from VP connection between 2 and SW-3
Secure resources such as links and bands, and switch device S
Connection control device BCCS-3 for controlling W-3
The switch device SW-2 secured by the inter-switch connection identifier, the inter-switch device connection end point identifier, the bearer information and the connection control device BCCS-2.
VC link identifier between SW3 and SW3 (link identifier)
Is specified to make a connection generation / connection request 3-3.

When the connection control device BCCS-3 receives this request 3-3, the connection control device BCCS
Switch devices SW-2 and SW notified from CS-2
Resources such as a VC link between 3 and a band are secured. At this time, the end point on the switch device SW-3 side becomes one end point of the inter-switch device connection. Further, the connection control device BCCS-3 knows that the switch SW-3 is the end point of the inter-switch device connection from the inter-switch device connection end point accommodating position information or the inter-switch device connection end point identifier, and informs the connection control device BCCS-2. , Inter-switch device connection identifier, inter-switch device connection end point identifier, and result (success) notification 3-4.

When the connection control device BCCS-2 receives this notification 3-4, the connection control device BCCS
The CS-1 is notified of the inter-switch device connection identifier, the inter-switch device connection end point identifier, and the result (success) notification 3-5.

When the connection control device BCCS-1 receives this notification 3-5, the connection control device BCCS
The CS-1 is notified of the inter-switch device connection identifier, the inter-switch device connection end point identifier, and the result (success) notification 3-6.

In the request to generate the connection between switch devices, the call control device as the request source determines the level of the end of the switch device that accommodates the end point as the end point designation level in the inter-switch device connection end point identifier or the inter-switch device connection end point accommodation position information. Identifier or endpoint identifier, VP connection identifier,
Three are allowed, specified by the VC link identifier. At this time, the requested connection control device selects and secures a usable VC link from within the specified level range. In selecting a VC link, if the end point is designated by the VC link identifier, that VC link may be in use.

Request for generation of connection between switch devices from call control device to connection control device (in case of the above-mentioned example, connection request between switch devices generation / connection request 3)
-1), or a connection creation request between the connection control devices (also a connection creation / connection request 3-
In 2, 3-3), it is necessary to specify at least one of the inter-switch-device connection end-point identifier and the inter-switch-device connection end-point accommodating position information for the home side or mate side end point of the inter-switch device connection. However, when both the inter-switch device connection end point identifier and the inter-switch device connection end point accommodating position information are designated, the contents of the information must be consistent.

The end point of the inter-switch device connection is designated by the inter-switch device connection end point accommodation position information,
If it is found from the contents that both end points are accommodated in the same switch device, the request destination connection control device secures resources such as links and bands within the range specified by the inter-switch device connection end point accommodating position information (end point is V
If specified by the C link identifier, that VC link may be in use), and further, among the secured VC links, the home side VC link is requested as the mate side switching device connection end point identifier. Notify the original call control device together with the result (success).

As a method of advancing the processing between the connection control devices when the bidirectional connection is generated and connected,
[Method 1] A method in which a connection control device of a connection generation / connection request source secures resources such as bidirectional VC links and bandwidths, and [Method 2] a connection control device of a connection generation / connection request source connection control device. Resources such as VC link and band are secured from the input VP connection to the switch device controlled by the device,
There are two possible methods of securing resources such as VC links in the reverse direction and bandwidth in the connection control device that is the connection generation / connection request destination. In the case of method 1, in the above example, the connection control device BCCS-2 requests 3
Between the transmission of S-2 and the transmission of the request 3-3
It is possible to generate and connect a VC connection between the switch device SW-1 and the switch device SW-3 by controlling W-2. On the other hand, in method 2, the bidirectional VC link is established only after receiving the notification 3-4.
While receiving the notification 3-4 and transmitting the notification 3-5, the switch device SW-2 is controlled to generate / connect a VC connection.

The connection route may be notified to each connection control device by determining all routes by the request destination connection control device (BCCS-1 in the above example) for connection generation between switch devices. All routes may be individually determined with.

The inter-switch device connection identifier is a connection control device (BCCS-1, BCCS- in the above example) for controlling both end points of the inter-switch connection.
2) manages. It is not always necessary to manage the inter-switch-device connection identifier in the connection control device (also BCCS-2) that controls the switch device (also SW-2) that relays the connection between switch devices.

3.3 Disconnection / Release of Connection between Switch Devices Based on the configuration of FIG. 1, a sequence for simultaneously disconnecting / releasing a connection between switch devices that has already been generated / connected will be described.

3.3.1 First Sequence Example FIG. 4 shows a first example of the disconnection / release sequence of the connection between switch devices. In this example, the disconnection / release of the connection between the switch devices is confirmed only between the request source call control device and the request destination connection control device.

First, the call control device CCS-1 designates the inter-switch device connection identifier and makes a connection disconnection / release request 4-1 between the switch devices to the connection control device BCCS-1.

When the connection control device BCCS-1 receives this request 4-1, the switch device SW-1, which has been secured in connection with the connection between the switch devices,
Resources such as VC link and band between SW2
The link is released unless the link is shared with other intra-switch device connections, and the management information of the inter-switch device connections is released. Furthermore, connection control device B
The CCS-1 designates the VC link identifier secured between the switch devices SW-1 and SW-2 to the connection control device BCCS-2, and requests the disconnection / release of the connection 4-
2 is sent and the result (success) is notified to the call control device CCS-1 4-4.

When the connection control device BCCS-2 receives the request 4-2, the connection control device BCCS-2
From the VC link identifier between the switch devices SW-1 and SW-2 notified from -1, the VC link between the switch devices SW-1 and SW-2 that has been secured and connected in association with the VC link identifier is determined, and these VCs are determined. Resources such as links and bands are released, and the switching device SW-2 is controlled to disconnect / release the connection between these VC links. The connection control device BCCS-2 also releases the information managed in connection with the connection between the switch devices, and further secures the information between the switch devices SW-2 and SW-3 in the connection control device BCCS-3. Connection disconnection / release request 4 by specifying the link identifier of the VC link
-3.

When the connection control device BCCS-3 receives this request 4-3, the connection control device BCCS
Switch devices SW-2 and SW- notified from CS-2
Resources such as a VC link and band between the three switch devices are released unless the VC link is shared with another intra-switch device connection, and information regarding the corresponding inter-switch device connection is deleted.

Upon receiving the notification 4-4, the call control device CCS-1 releases the management information regarding the connection between the switch devices.

When the connection control device BCCS-2 controlling the relay switch device SW-2 manages the inter-switch device connection identifier, instead of the link identifier in the connection disconnection / release request between the connection control devices. A connection identifier between switch devices can also be specified.

3.3.2 Second Sequence Example FIG. 5 shows a second example of the disconnection / release sequence of the connection between switch devices. In this example, the disconnection / release of the connection between the switch devices is confirmed between the request source call control device and the request destination connection control device, and between the adjacent connection control devices.

Also in this case, the call controller CCS-1 is
By designating the connection identifier between switch devices, the connection control device BCCS-1 is requested to disconnect / release the connection between switch devices 5-1.

When the connection control device BCCS-1 receives this request 5-1 the adjacent connection control device BCCS- related to the connection between the switch devices.
2, the link identifier of the VC link between the switch devices SW-1 and SW-2, which has been secured in relation to the connection between the switch devices, is designated, and the connection disconnection / release request 5-2 is performed. Connection control device BCCS-1
Also sends the call controller CCS with the sending of the request 5-2.
The result (success) is notified to -1 5-6.

Upon receiving the request 5-2, the connection control device BCCS-2 receives the notified switch device SW-.
From the VC link identifier between SW1 and SW-2, the switch devices SW-1 and SW- which are secured and connected in association with the VC link identifier
The VC link between the two is determined, and resources such as the VC link and the band are released. Also, the switch device SW
-2 to control the disconnection between these VC links.
release. Furthermore, the connection control device BCCS-1
To the connection control device BCCS-3 by switching the switch devices SW-2 and SW-3.
A VC disconnection request is made by designating a VC link identifier between them.

Upon receipt of this request 5-3, the connection control device BCCS-3 receives the notified switch device S.
Resources such as a VC link and band between W-2 and SW-3 are released unless the VC link is shared with another intra-switch device connection, and information related to the inter-switch device connection related thereto is deleted. Then, the connection control device BCCS-2 is notified of the result (success) 5-4.

When the connection control device BCCS-2 receives this notification 5-4, the switch devices SW-2, S
Resources such as VC link and band between W-3
Unless the link is shared with another intra-switch device connection, the link device is released and the information about the inter-switch device connection associated with the VC link is deleted.

When the call control device CCS-1 receives the notification 5-5, the VC between the switching devices SW-1 and SSW-2 is received.
Resources such as links and bands are released as long as the VC link is not shared with other intra-switch device connections, and information regarding the inter-switch device connections associated with the VC link is deleted.

When the call control device CCS-1 receives the notification 5-6, it releases the management information regarding the connection between the switch devices.

When the connection control device BCCS-2 controlling the relay switch device SW-2 manages the inter-switch device connection identifier, instead of the link identifier in the connection disconnection / release request between the connection control devices. The connection identifier between switch devices may be designated.

3.3.3 Third Sequence Example FIG. 5 shows a third example of the disconnection / release sequence of the connection between switch devices. In this example, confirmation of disconnection / release of the connection between switch devices is performed between the request source call control device and all connection control devices related to the connection between switch devices.

Also in the case of this sequence, the call controller C
The CS-1 designates the connection identifier between the switch devices and makes a request 6-1 for disconnecting / releasing the connection between the switch devices to the connection control device BCCS-1.

When the connection control device BCCS-1 receives this request 6-1, the connection control device BCCS-2 related to the connection between the switch devices.
Then, the link disconnection / release request 6-2 is performed by designating the link identifier of the VC link between the switch devices SW-1 and SW-2 which has been secured in association with the inter-switch device connection.

When the connection control device BCCS-2 receives the request 6-2, the notified switch device SW-
From the VC link identifier between SW1 and SW-2, the switch devices SW-1 and SW- which are secured and connected in association with the VC link identifier
The VC link between the two is determined, the switch device SW-2 is controlled, and the connection between these VC links is disconnected / released. Further, the connection control device BCCS-2 is different from the connection control device BCCS-3 in that the switch device SW-
2, a VC link identifier between SW-3 is designated and a connection disconnection / release request 5-3 is made.

Upon receiving this request 6-3, the connection control device BCCS-3 receives the notified switch device S.
Resources such as a VC link and band between W-2 and SW-3 are released unless the VC link is shared with another intra-switch device connection, and information regarding the inter-switch device connection is deleted to establish a connection. The control device BCCS-2 is notified of the result (success) 6-4.

When the connection control device BCCS-2 receives the notification 5-4, the connection control device BCCS-2 switches SW-1, S-1.
Resources such as VC link and band between W-2 are released, resources such as VC link and band between switch devices SW-2 and SW-3 are released, and all information about connection between switch devices is erased. Then, the result (success) notification 6-5 is sent to the connection control device BCCS-1.

When the connection control device BCCS-1 receives this notification 6-5, the connection control device BCCS-1 switches SW-1, S-1.
Resources such as a VC link and band between W-2 are assigned to the VC.
Unless the link is shared with the connection in another switch device, the information related to the connection between switch devices is deleted and the result (success notification 6-6) is given to the call control device CCS-1.

Upon receiving the notification 6-6, the call control device CCS-1 releases the information managed in connection with the inter-switch device connection.

When the connection control device BCCS-2 controlling the relay switch device SW-2 manages the inter-switch device connection identifier, instead of the link identifier in the connection disconnection / release request between the connection control devices. The connection identifier between switch devices may be designated.

4. Control of intra-switch connection A case where the call control device controls the intra-switch device connection with respect to the connection control device will be described.

4.1 Attribute Information on Device Connection in Switch The attribute information representing the connection in the switch device is as follows.
The (1) switch device internal connection identifier, (2) switch device internal connection end point identifier, (3) switch device internal connection end point accommodation position information, and (4) bearer information are used.

The switch device connection identifier is information for uniquely identifying the switch device connection among the devices. The condition is that at least the call control device and the connection control device can be uniquely identified.

The in-switch-device connection end point identifier is information for identifying an end point (which also designates an information transfer source end point and an information transfer front end point) for setting the in-switch device connection. The structure of this information is based on the structure shown in FIG. 2 and is a combination of an information transfer source and an information transfer destination.

The in-switch-device connection end point accommodation position information is information representing the end point of the in-switch device connection by a different expression from the in-switch-device connection end point identifier. Here, the terminal end of the connection in the switch device is represented by another terminal accommodating connection identifier or the inter-switch device connection identifier. The bearer information is information on the bandwidth, quality, etc. allocated to the connection in the switch device.

4.2 Generation of Connection in Switch Device When generating a connection in the switch device, the call control device makes the connection identifier in the switch device, the connection end point identifier in the switch device, the connection end point accommodation position information in the switch device, and the bearer. By specifying the information, a connection creation request in the switch device is issued to the connection device. As the connection identifier in the switch device, for example, a combination of the identifier of the request source call control device and a number unique within the request source call control device is used. As the connection end point accommodation position information in the switch device, information on the information transfer source end point and the information transfer front end point is used.

When the VC link can be specified for the end point of the connection in the specified switch device, the connection control device of the request destination, via the control of the switch device, moves from the specified information transfer source end point to the information transfer front end. Execute the connection creation process that secures the resource in the switch to the point. In addition, when the end point is specified by the connection end point accommodation position information in the switch device connection and the specified terminal accommodation connection or inter-switch device connection is not created, the VC link to be the end point cannot be specified, and thus these connection After the generation is waited and the VC link can be specified, the connection generation processing is performed via the switch device. The control of waiting for the VC link to be specified and performing the processing is called "queuing control". After the processing is completed, the request source control device is notified of the result by indicating the connection identifier in the switch device.

In the switch device connection generation request, at least one of the switch device connection end point identifier and the switch device connection end point accommodation position information must be designated. When both the in-switch device connection end point identifier and the in-switch device connection end point accommodating position information are specified, no contradiction should occur between the two pieces of information.

4.3 Connection of connection in switch device When the call control device designates the identifier of the connection in the switch device that has already been created in the connection control device and makes a connection request of the connection in the switch device, the requested connection control is performed. The device is controlled by V via the control of the switch device.
Connection processing between C links is performed, and the result is notified to the request source call control device.

4.4 Disconnection in Switch Device Connection When the call control device issues a disconnection request in the switch device connection by designating the identifier of the connection in the switch device that is already connected to the connection control device, the request destination connection control is performed. The device is controlled by V via the control of the switch device.
The disconnection process between the C links is performed, and the request source call control device is notified of the result.

4.5 Release of Connection in Switch Device When the call control device requests the release of the connection in the switch device by designating the identifier of the connection in the switch device that has already been generated in the connection control device, the connection control in the requested destination is controlled. The device is controlled by V via the control of the switch device.
Release processing between C links is performed, and the result is notified to the request source call control device.

5 Call Processing Sequence In the configuration shown in FIG. 1, the terminal T-1 is the calling side and the terminal T is the calling side.
With -2 as the destination side, the flow of the entire call processing using the control of the terminal accommodation connection endpoint, the inter-switch device connection and the intra-switch device connection described above will be described. Tables 1 and 2 show the messages used in the call processing sequence and their meanings.

[0104]

[Table 1]

[0105]

[Table 2]

5.1 Call Connection Sequence The flow of processing from the call of the terminal T-1 to the start of communication will be described below. The first and second examples show the sequence when connecting the inter-switch device connection from the destination side, and the third example shows the sequence when connecting the inter-switch device connection from the originating side.

5.1.1 First Example of Call Setup Sequence FIG. 7 shows a sequence at the time of call connection. Tables 3 to 6 show the names of the messages used in this sequence and their parameters. The processing of the device is shown in Tables 7-10. In this example, the incoming call control device generates and connects an inter-switch device connection after receiving a call setup response from the incoming terminal.

[0108]

[Table 3]

[0109]

[Table 4]

[0110]

[Table 5]

[0111]

[Table 6]

[0112]

[Table 7]

[0113]

[Table 8]

[0114]

[Table 9]

[0115]

[Table 10]

5.1.2 Second Example of Call Setup Sequence FIG. 8 shows a message sequence at the time of call connection. Tables 11 to 14 show the names of the messages used in this sequence and their parameters. Tables 15 to 18 show the treatments of the prepared apparatus. In this example, the incoming call control device generates and connects an inter-switch device connection after receiving a call setup response from the incoming terminal. The difference from the sequence shown in the first example is that the generation and connection of the connection in the switching device on the calling side is made to wait control.

[0117]

[Table 11]

[0118]

[Table 12]

[0119]

[Table 13]

[0120]

[Table 14]

[0121]

[Table 15]

[0122]

[Table 16]

[0123]

[Table 17]

[0124]

[Table 18]

5.1.3 Third Example of Call Setup Sequence FIG. 9 shows a message sequence at the time of call connection. Tables 19 to 23 show the names of the messages used in this sequence and their parameters. Tables 24 to 27 show the treatments of the prepared apparatus. In this example, before the call control device sends a call setup request to the call control device, the connection between switch devices is generated and connected.

[0126]

[Table 19]

[0127]

[Table 20]

[0128]

[Table 21]

[0129]

[Table 22]

[0130]

[Table 23]

[0131]

[Table 24]

[0132]

[Table 25]

[0133]

[Table 26]

[0134]

[Table 27]

As described above, in the above call setting sequence, by combining the control of the terminal accommodation connection end point, the intra-switch device connection, and the inter-switch device connection, the VC connection for information transfer between terminals can be set from the originating side to the terminating side. It is possible to set from.

Further, in the above call setting sequence, in the request for generation / connection of the inter-switch device connection from the call control device, the end point of the connection is designated by the inter-switch device connection end point accommodation position information. The request source connection control device determines whether the two end points of the inter-switch device connection are accommodated in different switch devices or in the same switch device, and performs inter-switch device connection generation / connection processing to perform inter-switch device connection processing. Notify the connection endpoint identifier. Therefore, the call control device can perform the call processing in the same procedure without paying attention to whether the switching devices accommodating the calling and receiving terminals are the same or different. In the generation and connection processing of the connection between switch devices within the same switch device, the request destination connection control device uses the home side VC link among the selected and secured VC links as the mate side switch device connection end point identifier, and the mate side The VC link is notified to the request source call control device as the home end switching device connection end point identifier. Therefore, for example, in the call setting sequence shown in the first example, the call control device on the receiving side generates the connection in the switching device after receiving the call setting response from the receiving terminal, and As the end point, one specifies the terminal accommodation connection end point of the destination side, and the other specifies the terminal accommodation connection end point of the originating side notified as the end point of the inter-switch device connection.

In the second example of the call setting sequence, the waiting type switch device connection can be generated and connected, as in the switch device connection generation and connection request of the message 8-4. As a result, as compared with the first example, it is possible to simplify the sequence from the call setup response of the destination terminal to the start of communication, and it is possible to suppress the influence of disconnection of the talk.

In the above call setting sequence example, bidirectional connection control, for example, generation and connection can be performed for each direction, so that, for example, in the above-mentioned second example sequence, the switch device on the calling side is connected. The internal connection can be set so that only the information transfer from the receiving side to the calling side can be performed in the processing of the message 8-4, and the information transfer from the calling side to the receiving side can be performed after receiving the message 8-21. .

In the sequence shown as the first example or the second example, the generation and connection of the inter-switch device connection are activated from the receiving side after the call setting response of the receiving terminal. It is also possible to generate and connect before the call request to the destination terminal for call setup. In this case, the connection within the switch device on the receiving side may be generated in advance of the call setting response of the destination terminal, and the connection within the switching device may be connected after receiving the call setting response of the destination terminal.

The destination terminal transmits the call setting response after receiving the call setting request, but it can also send the call setting acceptance before the call setting response. In addition, conventional CCIT recommendation Q. 93
1 or NO. As in the procedure of 7, the call notification process may be performed between the call setting acceptance transmission and the call setting response.

In the above description, the control of the terminal point of the terminal-accommodating connection, the control of the connection within the switch device, and the control of the connection between switch devices are individually performed. It is also possible to combine the control of the inter-device connection into one control. in this case,
It is possible to degenerate the message sequence between the call controller and the connection controller.

The case where the call control device controls the connection control device to set the VC connection for information transfer between the terminals has been described, but the same control is performed by the operation management system device to the connection control device. It is also possible to set a control connection (VC connection) between the devices.

5.2 Call Disconnect / Release Sequence FIG. 10 shows a message sequence from during communication until the call is disconnected and released, and Tables 28 and 29 show the contents of the message used in this sequence and its parameters. Tables 30 to 32 show the processing of the device that received the message. Here, the procedure for disconnecting and releasing the call from the calling side is shown, but the procedure for disconnecting and releasing the call from the called side is also the same. As the procedure for disconnecting / releasing the connection between the switch devices, the method described above can be used in addition to the method shown in FIG.

[0144]

[Table 28]

[0145]

[Table 29]

[0146]

[Table 30]

[0147]

[Table 31]

[0148]

[Table 32]

[0149]

As described above, in the present invention, the call control unit and the connection control unit are separated as independent devices and are connected to each other by the control connection. Therefore, the call control unit and the connection control unit can be freely arranged, software can be optimally arranged, and resources such as bandwidth can be effectively used. Further, the call control device is used for communication between terminals accommodated in different switch devices and
It is possible to realize communication between terminals accommodated in one switch device by the same procedure, and it is also possible to set information transfer connection between terminals from the originating side and the receiving side. .

[Brief description of drawings]

FIG. 1 is a block configuration diagram of a communication system according to an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of an endpoint identifier.

FIG. 3 is a diagram showing a sequence of connection generation / connection between switch devices.

FIG. 4 is a diagram showing a first example of a sequence of disconnecting / releasing a connection between switch devices.

FIG. 5 is a diagram showing a second example of a sequence of disconnecting / releasing a connection between switch devices.

FIG. 6 is a diagram showing a third example of a sequence of disconnecting / releasing a connection between switch devices.

FIG. 7 is a diagram showing a first example of a call setup sequence.

FIG. 8 is a diagram showing a second example of a call setup sequence.

FIG. 9 is a diagram showing a third example of a call setup sequence.

FIG. 10 is a diagram showing a call disconnection sequence.

[Explanation of symbols]

BCC-1 to 3 connection control device CCS-1, 2 call control device CON-1, CON-2 connection part SW-1 to 3 switch device T-1, 2 terminal VCL-1 to 6 VC link VPC-1 to 4 VP connection CC-CC-1, CC-BCC-1, 2, BCC-BC
C1, 2, BCC-SW-1 to 3, T-CC-1, 2
Control connection

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Isao Saito 1-1-6, Saiwaicho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corporation

Claims (1)

[Claims] 1. A channel connection is created by terminating one or more path connections each including a plurality of channel links capable of transmitting information, and connecting the channel links included in the path connections between the terminated path connections. A plurality of switch devices to be formed are provided, and the plurality of switch devices and the individual switch devices and the terminals accommodated therein are connected by a path connection, and the formation of the channel connection in each of the plurality of switch devices is controlled. In the communication system, the control means includes a call control device that performs a service control including intercommunication between the terminals in response to a request from the terminal, and information transfer between the terminals under the control of the call control device. Connection control to set or release channel connection for Control device separately, the call control device is provided with means for managing a call state and means for transmitting / receiving a call control message, and the connection control device controls the switch device. A means for setting or releasing a channel connection, a means for managing the relationship between a path connection and a device that terminates the path connection, and the usage status and availability of the channel link included in the path connection terminated by the switch device. And a routing means for deciding a setting route of a channel connection.