JP3050814B2 - Communications system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
N (Broad band-Integrated Services Digital Networ
k) (hereinafter referred to as I)
It is called N. ) Multiple subscribers (multi-party)
The present invention relates to a communication system provided with a service control device for providing a connection service to a communication device and an exchange.

[0002]

2. Description of the Related Art As one of promising services in B-ISDN, multi-party connection services such as point-to-multipoint connection and multipoint / multipoint connection are conceivable. Also in the ITU-T, the standardization of the B-ISDN signaling system for realizing these multi-party connection services is being actively promoted (prior art document 1).
“ITU-T Recommendation,“ B-ISDN Signaling Capability S
et 2 Draft Recommendations in Q.2000 series ”, 1995
Year "and Prior Art Document 2" ITU-T Recommendation, "Broadban
d Capability Set 3 Signalling Requirements, "TD1 / 11
-53, April-May 1995 ". ).

On the other hand, an additional service accompanying the multi-party connection service is provided by an intelligent network (I
N) There is also a study to be realized based on the architecture, and several call models in IN on B-ISDN have been proposed. In the IN on the B-ISDN, a connection and a party are newly added as targets of modeling or control in addition to the conventional call. B
CSM (Basic Call State Model)
For example, a high-level finite state machine model expressing basic call processing for a normal call that does not require supplementary services. ), A method of using an integrated state model for all parties involved in a call (prior art document 3)
“Mukasa et al.,“ Proposals of Call Modeling for
Intelligent Network over Broadband ISDN ", GLOBECOM9
5, Vol. 2 of 3, pp. 1265-1271, November 1995 ”and prior art reference 4“ Maastrichit et al., “Call Modeling in a B
roadband IN Architecture ", ISS'95, A7.5, April 1995"
reference. ) And a method of preparing an individual state model for each party connected to each connection by following the conventional departure and arrival type BCSM (prior art document 5 “Wakamo
to et al., “Intelligent Network Architecture with
Layered Call Model for Multimedia-on-DemandServic
e ", ISS'95, P.g2, April 1995" and prior art document 6, "Carm
agnola et al., “A Layered Approach for IN Call Mode
lling for the Support of MultimediaServices in a B
-ISDN Environment ", ICC'96,32.3, pp.952-956,1996
Month ". ) Has been proposed. The former method is desirable from the viewpoint that party control can be performed independently and the simplicity of the model.

[0004]

In the system using the integrated BCSM, when a multi-party connection is made, one DP (Detection Point: a processing event is reported to the service control function, and the transfer of the processing control is performed. It is conceivable that a plurality of services for a plurality of parties are activated from the point of the basic call processing when it occurs. Conventional DP processing method (Prior art document 7 “I
TU-T Recommendation, “Distributed Functional Plane for In
telligent Network CS-1 ", Recommendation Q.1214,1995
See year. In the case of), when a plurality of services are set in one DP, those services can be started only sequentially, so that the number of parties increases and the service processing time increases, and the service quality deteriorates. There was a problem of doing it.

An object of the present invention is to solve the above problems and to provide a communication system capable of improving service quality by shortening service processing time for multi-party service processing as compared with the conventional example. It is in.

[0006]

SUMMARY OF THE INVENTION A communication system according to the present invention executes a service process for an exchange in a network to which a plurality of subscriber terminals are connected and for a plurality of different subscribers connected to the exchange. Requesting the service control device to execute a predetermined service process by executing a detection point process by the exchange, and in response to the request, the service control device executes the service process. In the communication system to execute, the exchange performs a predetermined service process for each of a plurality of different subscribers by generating and executing a sub-detection point process, which is an extension of the detection point process, for each of the subscribers. Requesting the service control device to perform the operation, and in response, the service control device Respectively serial different subscribers and executes the service process.

[0007]

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

In order to solve the above-mentioned problem, in the embodiment according to the present invention, the conventional DP processing (detection point processing) 11 is extended so that a plurality of service processes for a plurality of different parties are time-divided. , And the service processing time of the communication system as a whole is reduced. That is, in the communication system of FIG. 2, in the conventional example, as shown in FIG.
The service processing for each subscriber was sequentially executed.
As shown in (b), a plurality of service processes for a plurality of different parties are executed in a time-division manner in parallel. The service processing includes a call transfer service from one subscriber terminal to another subscriber terminal, a screening service for checking whether connection is permitted, for example, whether to charge a credit card. The service includes an incoming billing service to be determined.

[0009] In the present embodiment, the prior art document 7 describes that a service processing request to different parties set in one DP can be simultaneously issued to the service control function.
Is extended. Basically, a method in which the parent DP processing 11 generates a child sub-DP processing 14-1 to 14-m (collectively denoted by 14) corresponding to each party. Is used.

FIG. 1 shows an embodiment B according to the present invention.
FIG. 1 is a block diagram illustrating a configuration of a communication system including a service control device 20 and a switch 10 that provide a connection service to a plurality of subscribers in an intelligent network for ISDN. As shown in FIG. 1, for example, an exchange 10 such as an LS (local) exchange has terminals 30A, 30B, 30B ', 30C, 30 of a plurality of subscribers.
C ′ is connected, and the connection between the exchange 10 and the service control device 20 is connected. The service control device 20 is connected to a database memory 22 that stores information on a plurality of subscribers connected to the exchange 10 and setting information on what kind of service processing is to be performed on each subscriber. The control programs built in the exchange 10 are roughly classified into the following three processes. (A) DP (Detection Point: detection point; refers to a point in basic call processing when a processing event is reported to the service control function and transfer of processing control occurs) processing 11, that is, service processing to the service control device 20 (B) Call Control Functional Entity (CCF): a functional entity that cooperates with each other to provide a call processing function of a network. 12, call processing at each switch in the network; and (c) Feature Interaction Manager (FIM): a process of managing the interaction of services; the action of one service affects the action or capability of another service. Is a management process of a state that occurs when the service control device is provided. SLP processing in the 20 2
This is the process that controls the interface process with the C.I.

In the present embodiment, the DP process 11 is extended, and a plurality of sub-DP processes 1
By generating and executing 4-1 to 14-m, a plurality of service processes are executed in parallel. Service control device 2
0 is a control program built in SLP (Service Lo
gic Processing Program: a service logic processing program; a software program containing service logic. ) Process 21, that is, a process of executing a predetermined service process with reference to the database information in the database memory 22.

The exchange 10 and the service control unit 20
Are each provided with an electronic computer having one CPU, and the service control device 20 executes a plurality of service processes in a time-division manner in parallel. Note that an entity is a device or system that is individually separated, and an event is a specific input and output from a given state in a finite state machine that causes a transition from one state to another state. And / or output.

As an example of the operation in the communication system of FIG. 1, a case where a subscriber A requests connection to subscribers B and C is shown as an example. In this case, if the subscribers B and C are respectively transferring incoming calls to the subscribers B 'and C', the service control unit 20 performs a call transfer service process for the subscribers B and C. Are executed in parallel, the overall service processing time can be reduced. That is, the service processing time can be shortened by sending two call transfer service processing requests from the exchange 10 to the service control device 20 simultaneously, not sequentially. More specifically, when performing service processing for each of a plurality of different subscribers, the exchange 10 performs a plurality of sub-detection point processes, which are extensions of the above-described detection point process, on a service process for the plurality of different subscribers. The service control apparatus 20 requests the service control apparatus 20 to execute service processing for each of a plurality of different subscribers by generating and executing each service, and in response to the request, the service control apparatus 20 executes time-divisional parallel processing. Then, the service processing is executed for each of the plurality of different subscribers.

Here, DP set in BCSM
Table 1 shows the types.

[0015]

[Table 1] タ イ プ DP type arming service processing request and call processing mechanism Judgment condition whether to put out Suspension (interruption) ─────────────────────────────────── TDP-R static Target Yes Yes Ｔ TDP-N Static Yes No ───── ────────────────────────────── EDP-R Dynamic No Yes ───────────── ────────────────────── EDP-N Dynamic None None ───────────────────── ──────────────

In Table 1, "Dynamic Arming" means that the DP is set by the service control function during the execution of the service control for a specific call / service. Static Arming is a service management function that indicates that when a specific point in call processing / service processing is reached, a predetermined action can be taken by the call processing / service processing. This means that the DP is set in advance. Therefore, TD
PR (Trigger Detection Point-Request: Trigger D
P-request) notifies the DP in the statically armed basic call processing and interrupts the call processing (requests a reply).
Setting, TDP-N (Trigger Detection Point-No
Tification (trigger DP-notification) is a setting for notifying the DP in the statically armed basic call processing and not interrupting the call processing (not requesting a reply). Also, E
The DP-R (Event Detection Point-Request) is a setting for notifying the dynamically armed DP and interrupting the call processing (requesting a reply).
PN (Event Detection Point-Notification: Event DP-Notification) is a setting that does not interrupt call processing (does not request a reply) but only notifies a dynamically armed DP.

FIG. 4 is a flowchart showing the DP processing 11 executed in the exchange shown in FIG. 1. FIGS. 5 and 6 show the sub-DP processing 1 executed in the exchange shown in FIG.
6 is a flowchart illustrating a fourth example.

In the DP processing 11 shown in FIG.
When a DP processing request from the call processing side (CCF processing 12) is received from the idle state of Step 1 (Step S2), a child sub DP processing 14 is generated for all parties (Step S3). S4), and waits for reception in step S5. In this state, when a call processing restart request is received from a sub process of the sub DP processing 14 (step S11), it is checked whether a call processing restart request has been received from all the sub DP processing 14 processes (step S12). If it has been received, a call processing restart request is returned to the call processing side (CCF processing 12) (step S13).
Return to 5). On the other hand, when a transition request from the process of the sub DP processing 14 to the initial state is received in the reception waiting state of step S5 (step S21), a disconnection request is transmitted to all other existing sub DP processing 14 processes. Then (step S23), a request for transition to the initial state is returned to the call processing side (CCF processing 12) (step S25), and the apparatus enters the idle state of step S1. Further, step S5
When a call release request is received from the call processing side (CCF processing 12) in the reception waiting state (step S24), a disconnection request is transmitted to all existing sub DP processing 14 (step S23). A request for transition to the initial state is returned to the call processing side (CCF processing 12) (step S2).
5) The idle state is set in step S1.

In the sub-DP processing 14 shown in FIG. 5, any one of DP, EDP-N, TDP-N, EDP-R and TDP-
The presence or absence of the setting is checked in the order of R (steps S31 to S35). If nothing is set, a call processing restart request is returned to the DP processing 11 (step S41), and the process of the sub DP processing 14 is extinguished. In FIGS. 5 and 6, x indicates that the generated sub DP processing 14 is to be deleted. When EDP-N is set (YES in step S32), a notification request is transmitted to SLP process 21 of service control device 20 via FIM process 13 (step S42), and the process returns to step S32. here,
In response to the notification request, the service control device 20 executes a corresponding notification service process in the SLP process. When TDP-N is set (step S33)
Only when the predetermined trigger condition is satisfied (YES in step S38), a notification request is transmitted to the SLP process 21 of the service control device 20 via the FIM process 13 (step S43), and the process returns to step S33. Here, in response to the notification request, the service control device 20
The LP process 21 is executed. If the trigger condition is not satisfied in step S38, the process returns to step S33. Furthermore, E
When DP-R is set (YE in step S34)
S), a DP request (DP request) is transmitted to the SLP process 21 of the service control device 20 via the FIM process 13 (step S44), and the reception wait state is set (step S45). Here, in response to the DP request, the service control device 20 executes a corresponding service process in the SLP process.

When a so-called single point of control condition exists for each party, a plurality of EDP-Rs are not set. TD
When PR is set (YE in step S35)
S), the trigger condition is satisfied (YE in step S36)
S), other control relationships with the service control function (Contro
l Relationship) does not exist (YES in step S37), the DP request (DP request) is
The data is transmitted to the SLP processing 21 in the service control device 20 via the processing 13 (step S46), and the reception wait state is set (step S45). Here, in response to the DP request,
The service control device 20 executes the corresponding SLP processing 21. When all the service processes have been completed, that is, when the processes for all the DPs have been completed (step S
(YES at 35), a call processing restart request is returned to DP processing 11 (step S47), and the process of sub DP processing 14 is extinguished.

In the sub DP processing 14 of FIG. 6, when a processing result response from the SLP processing is received in the reception waiting state of step S45 (step S51), necessary processing such as setting of EDP is performed (step S61). When the response is the call processing restart in step S62, the next TDP
Continue searching for -R (step S63). That is, when TDP-R is set in step S63, FIG.
Go to step S36. On the other hand, in step S63, TD
If PR is not set (N in step S63)
O), a call processing restart request is returned to the DP processing 11 (step S64), and the sub DP processing 14 is extinguished. If the response is a request for transition to the initial state in step S62, the request for transition to the initial state is returned to the DP processing 11 (step S65), and the process of the sub DP processing 14 is extinguished. In the reception waiting state of step S45, when a timeout or error signal is received from the SLP processing 21 (step S52), necessary processing is performed (step S71), and a request for transition to the initial state is sent to the DP.
The process is returned to the process 11 (step S72), and the sub DP process 14 is deleted. Further, when a disconnection request is received from the process of the DP processing 11 in the reception waiting state of step S45 (step S5).
3), at step S81, ITU-T Recommendation Q.3; 1218
(Prior Art Document 8 “ITU-T Recommendation,“ Interface Reco
mmendation for Intelligent Network CS-1 ", Recommend
ation Q.1218, 1995 ". In accordance with the procedure specified in (1), the service control function is instructed to stop the service processing, and the process of the sub DP processing 14 is deleted.

FIG. 7 shows the interface processing 100 on the SSF side.
FIG. 8 shows the SCF side interface processing 2
00 shows the model No. 00. These figures are based on ITU-T Recommendation Q. 1218 (see Prior Art Document 8). In the conventional example, one SSF-FSM (Service Switch) is simultaneously set for one call from the condition of a single point of control.
Only a ching Function-Finite State Model) instance and one SCSM (Service Control State Model) instance occurred. Here, the SSF side interface processing 100 is a processing set that provides an interaction between the call control function and the service control function,
Refers to a system that has a finite number of states and has specific transitions between states. In addition, SCF (Service Control
The function-side interface process 200 is a process set that provides an interaction between the service logic application for controlling a functional entity in the intelligent network and another functional entity.

On the other hand, in this embodiment, even for one call, a plurality of SSF-FSM instances and SCS
There are cases where M instances occur. And multiple SLPIs corresponding to multiple SCSM instances
(Service Logic Processing Program (Use) Instanc
e: service logic program instance; refers to the implementation and application of a particular service logic program in providing a service or service feature for a particular call / service attempt. ) The processing is executed simultaneously. However, since these SLPI processes can be executed completely independently, the models themselves of FIGS. 7 and 8 can be applied to the present embodiment without any change. As described above, DSF has almost no effect on the SSF-SCF interface or the SCF itself.
Only by expanding the P processing 11, high-speed multi-party service processing can be realized.

[0024]

EXAMPLE The present inventor evaluated the effect of improving the service processing time in the communication system of the present embodiment by computer simulation. FIG. 9A is a block diagram showing an evaluation model in a computer simulation of a communication system of a conventional example, and FIG. 9B is a block diagram showing an evaluation model in a computer simulation of the communication system of the embodiment. In FIG. 9, λ represents the arrival rate of a multiparty service processing request call. N represents the number of parties to be serviced. Here, in each service process, the SDF is performed only once.
(Service Data Function: a function set that provides management of service data according to a service data template.) It is assumed that access to the process 400 is performed.

As shown in FIG. 9A, in the conventional example,
Since n service processes are executed sequentially, a series of DP process 11, SCF process 200, SD
The F process 400, the SCF process 200, and the DP process 11 are repeated a plurality of times n. Here, since the DP processing 11 is mainly a search processing of the trigger table, the processing time of the DP processing 11 is as follows.
Assume an exponential distribution with mean h ₁ . However, when service processing for the next party is started again after one service processing is completed, it is assumed that the service processing follows an exponential distribution with an average of 2 · h ₁ . Since SCF process 200 the time required for generating or erasing the service processing process seems to occupy a large portion, the processing time is assumed to constant distribution of h _2. Since the SDF processing 400 is a database search processing, it is assumed that the processing time follows an exponential distribution with an average h ₃ .

As shown in FIG. 9B, in this embodiment, one arriving multi-party service processing request call is divided into a plurality of n calls at the entrance, and the n calls are continuously It is processed. Each split call is a series of DPs
Process 11, SCF process 200, SDF process 400, SC
F processing 200 and DP processing 11 are received. Here, the DP processing 11 is mainly processing for generating or deleting a process of the sub DP processing 14 and processing for searching the trigger table.
It is assumed that the processing time of the P processing 11 follows a distribution obtained by combining a constant distribution of the average h ₁ ′ and an exponential distribution. The processing time of the processing time and SDF process 400 SCF process 200, similarly to the conventional example, a certain distribution and average h ₃ respectively h ₂
Is assumed to follow an exponential distribution of

Using the model of FIG. 9, the processing time of the service processing in the conventional example and the present embodiment was evaluated. Here, the processing time of the service processing refers to the time from the arrival of the service processing request call to the reception of the service processing a plurality of times n and the completion of the final DP processing 11 in the conventional example. Further, in the present embodiment, it indicates the time from the arrival of the service processing request call until the last of the divided calls receives the service processing and finishes the DP processing 11.

FIGS. 10 to 13 show the evaluation results of the service processing time. In FIGS. 10 to 13, h ₁ =
1 msec, h ₂ = 1 msec, h ₃ = 10 msec. The processing time of the DP processing 11 in the present embodiment is the processing time of the DP processing in the conventional example and the processing time of the SCF processing 2
00 is the sum of the processing times. That is, h
₁ ′ = 2 msec. The arrival rate of service processing request calls, which is a combination of a multi-party service processing request call (hereinafter referred to as an mp call) and a call requesting service only to one party (hereinafter referred to as a tp call), is 5 Calls / sec. Further, the DP processing server (switch 10) and S
The CF processing server (the service control device 20) is initially in a state where a 70% load is applied for other processing.
10 to 13, the measurement error of the service processing time is about 3%.

In FIGS. 10 to 13, mp calls and tp
The service processing time when the ratio of calls is changed is shown. In any case, it can be seen that the multi-party service processing time is significantly improved by the present embodiment. The improvement effect becomes more remarkable as the number of parties to be serviced increases. However, for the tp call,
Since the process of the sub DP process 14 is generated and deleted, the service processing time is slightly longer in the present embodiment.

10 to 13, as the number of service processes required by the mp call increases, the overall processing load increases, so that the service processing time of the tp call somewhat increases. Also, as the proportion of mp calls increases, the processing load also increases, so that the overall service processing time increases. However, if the ratio of mp calls is up to about 50%, the increase in service processing time is slight.

As described above, according to the embodiment of the present invention, the multi-party service processing required for providing the multi-party connection service which is one of the promising communication services in B-ISDN is performed at high speed. An apparatus can be provided. When the multi-party service processing is performed on the IN architecture using the integrated BCSM, the speed of the multi-party service processing can be increased by executing the service processing for each party in parallel in a time-division manner. This embodiment can be realized only by extending the existing DP processing 11. Further, from the result of the computer simulation, according to the present embodiment, the multi-party service processing time can be actually significantly reduced, and the service quality can be improved.

[0032]

As described above in detail, according to the communication system according to the present invention, a network exchange to which a plurality of subscriber terminals are connected, and a plurality of different subscribers connected to the exchange, respectively. A service control device for executing a service process, wherein the exchange requests the service control device to execute a predetermined service process by executing a detection point process, and in response to this, the service control device In the communication system that executes the service processing, the exchange generates and executes a sub-detection point process, which is an extension of the detection point process, for each of the subscribers, so that a predetermined number of different subscribers are provided. Requests the service control device to perform service processing, and in response, the service control device In each run the service process on the plurality of different subscribers in parallel. Therefore,
It is possible to provide a communication system capable of improving service quality by shortening the service processing time for multi-party service processing as compared with the conventional example.

[Brief description of the drawings]

FIG. 1 shows a B-ISDN according to an embodiment of the present invention.
FIG. 1 is a block diagram showing a configuration of a communication system including a service control device for providing a connection service to a plurality of subscribers and a switch in an intelligent network.

FIG. 2 is a block diagram showing an operation example of the communication system of FIG. 1;

FIG. 3 (a) is a timing chart showing processing with respect to the passage of time in a conventional communication system;
(B) is a timing chart showing processing with respect to the passage of time in the communication system of the present invention.

FIG. 4 is a flowchart showing a DP process executed in the exchange shown in FIG.

FIG. 5 is a flowchart showing a first part of a sub DP process executed in the exchange shown in FIG. 1;

FIG. 6 is a flowchart showing a second part of the sub DP process executed in the exchange shown in FIG. 1;

FIG. 7 is a block diagram showing a model configuration of an SSF-side interface process in the exchange shown in FIG. 1;

FIG. 8 is a block diagram showing a model configuration of an SCF side interface process in the service control device of FIG. 1;

FIG. 9A is a block diagram showing an evaluation model in a computer simulation of a communication system of a conventional example, and FIG. 9B is a block diagram showing an evaluation model in a computer simulation of the communication system of the embodiment.

FIG. 10 is a graph showing service processing time with respect to the number of parties performing service processing when mp call: tp call = 10%: 90% in a computer simulation of the communication system.

FIG. 11 is a graph showing a service processing time with respect to the number of parties performing service processing when mp call: tp call = 20%: 80% in a computer simulation of the communication system.

FIG. 12 is a graph showing service processing time with respect to the number of parties performing service processing when mp call: tp call = 50%: 50% in a computer simulation of the communication system.

FIG. 13 is a graph showing a service processing time with respect to the number of parties performing service processing when mp call: tp call = 100%: 0% in a computer simulation of the communication system.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Exchange, 11 ... DP processing, 12 ... CCF processing, 13 ... FIM processing, 14-1 thru | or 14-m ... Sub DP processing, 20 ... Service control apparatus, 21 ... SLP processing, 22 ... Database memory, 30A, 30B , 30B ', 30C, 30C'30D ...
Subscriber terminal.

Claims (1)

(57) [Claims] 1. A switchboard for a network to which a plurality of subscriber terminals are connected, and a service control device connected to the switchboard for executing service processing for each of a plurality of different subscribers. In a communication system in which the service control device requests the service control device to execute a predetermined service process by executing a point process, and the service control device executes the service process in response to the request process, Requesting the service control device to execute predetermined service processing for each of a plurality of different subscribers by generating and executing a sub-detection point processing for each of the above-mentioned subscribers by expanding the point processing, The service control device responds to the plurality of different subscribers in parallel in a time-division manner. Communication system and executes a-bis process.