WO2000062558A1

WO2000062558A1 - Menu service system

Info

Publication number: WO2000062558A1
Application number: PCT/FI2000/000275
Authority: WO
Inventors: Markku Laihonen; Juha Kavonius
Original assignee: Helsingin Puhelin Oyj
Priority date: 1999-03-30
Filing date: 2000-03-30
Publication date: 2000-10-19
Also published as: FI990703A0; FI990703A; AU3821200A

Abstract

In general, the invention relates to the implementation of voice service systems in a Public Switched Telephone Network. According to the invention, a telephone exchange controlling a certain subscriber extension transfers telephone calls coming to said subscriber extension under the control of the Service Control Point on the basis of at least one triggering condition for implementing a voice service in connection with said certain subscriber extension. The Service Control Point controls the calls further in accordance with the control rules saved in the SCP. The SCP can, for example, switch a call to the IP device and direct the IP device to give voice messages to the caller, for example. The Service Control Point can also switch the call further to another subscriber extension. The Service Control Point can also switch the call back to the extension to which the call was originally addressed, skipping the triggering conditions.

Description

MENU SERVICE SYSTEM

THE OBJECT OF THE INVENTION

In general, the invention relates to the implementation of voice service systems in a Public Switched Telephone Network. In particular, the invention relates to a method according to the preamble of Claim 1 for implementing a voice service system.

DESCRIPTION OF THE TECHNICAL BACKGROUND

One well-known way of implementing voice service systems in a Public Switched Telephone Network is the use of voice automation servers. A voice automation server is a device, which can play messages to a caller and receive the caller's selections on the basis of the DTMF (Dual Tone Multi Frequency) signals produced by the caller's telephone. In addition, the voice automation servers can typically save a message left by the caller and transfer the call further to another subscriber extension. A solution implemented with a voice automation server can be easily tailored to need, and the recording of messages is easy, because the service is implemented by means of one single server. As a drawback of the voice automation server it may be mentioned that the call transferred further is left to pass through the server, and thus two voice time slots are redundantly reserved from the connection line of the voice automation server. In addition, a voice automation server cannot utilize the versatile control operations of the Intelligent Network, which limits the possibilities of implementing voice services.

Another well-known way of implementing voice service systems is to utilize the functionality of an Intelligent Network (IN). This will be described in the following with reference to Fig. 1. Figure 1 shows a telephone 10, a Public Switched Telephone Network (PSTN) 20, a Service Switching Point (SSP) 30 of the PSTN, and a Service Control Point (SCP) 40 of the PSTN. The Service Switching Point and Service Control Point are network elements of the Intelligent Network (IN). The Service Switching Point (SSP) comprises, in addition to the switching functionality of a traditional telephone exchange, versatile functions for the automation of various services. The Service Control Point (SCP) does not transmit the actual voice data, but controls the operations of the Intelligent Network. Figure 1 also shows an Intelligent Peripheral (IP) device 50 of the Intelligent Network, which has in this case been implemented as a part of the Service Switching Point (SSP) 30. In a typical implementation of a voice service system, the control logic of the service has been implemented in the SCP, the voice messages of the voice service system have been saved in the LP device 50, and the SSP has been programmed to transfer the control of the call to the SCP, if the caller has selected a telephone number begi-αning with a certain series of digits. Series like this can be, for example, those begii-ning with 0800 in Finland or those begmning with 1800 in the United States. There may be several of these series of numbers, and thus the SSP may be programmed to transfer the control of the call to the SCP in all the cases that the caller calls a telephone number beginning with 0600, 0700 or 0800, for example.

When the caller makes a telephone call to a service number with the telephone 10, the call is directed via the telephone network 20 to the SSP 30, which examines which number the caller has selected. If the caller has selected a telephone number beginning with a certain series of digits, the SSP 30 transfers the control of the call to the SCP 40. The SCP examines which number the caller selected, and controls the call in accordance with the service determined by the number. The control rules of many different services may be saved in the SCP, whereby the service to be used, i.e. the set of control rules to be used are detei ined on the basis of the telephone number selected by the caller. The SCP controls the service given to the caller in accordance with the control rules of the service by giving commands to the IP device of the SSP, which plays the voice messages wanted. Such a voice service, which is based on the Intelligent Network, provides the advantage of using versatile control operations, such as time control or the implementation of services that change according to the time of the day, percentage control or switching calls to certain telephone numbers in certain proportions, overflow control or switching calls further to a second or third number if the first number does not answer or is busy, or change of tariff during the call, for example. Such a voice service based on the Intelligent Network has the drawback that the identification of the service number and directing it to the control point must be implemented in each SSP in the geographical area where the service should operate. As a result of this, making changes is difficult, and in this way the service can only be used with a telephone number beginning with a certain service series of digits. In addition, because the voice messages are saved in the internal IP device of each SSP in a solution like this, making changes and additions to the voice messages is also difficult, because there may be very many SSPs in the area where a certain service has been implemented, such as the area of a certain state. Short description of the invention

It is an objective of the invention to provide a method for implementing voice services in a Public Switched Telephone network, which method does not have the problems of the prior .art solutions mentioned above. It is also an objective of the invention to provide a method for implementing voice services in a Public Switched Telephone Network, by means of which method a voice service can be implemented in any telephone number. In addition, an objective of the invention is to provide a method for implementing voice services, whereby the service can be easily implemented and changed.

The objectives are achieved by arranging a telephone exchange, which controls a certain subscriber extension, to transfer telephone calls coming to the subscriber extension under the control of the service control point on the basis of at least one triggering condition for implementing a voice service in connection with said certain subscriber extension. The control point further controls the calls in accordance with the control rules saved in the control point. The control point can, for example, switch a call to the IP device and direct the IP device to give voice messages to the caller, for example. The control point can also switch the call further to another subscriber extension.

The method according to the invention is characterised in what is set forth in the characterising part of the independent claim concerning the method. The dependent claims describe other preferred embodiments of the invention.

SHORT DESCRIPTION OF THE FIGURES

In the following, the invention will be described in more detail with reference to the examples of preferred embodiments and the accompanying drawings, in which

Figure 1 shows a prior art system,

Figure 2 illustrates a solution according to a preferred embodiment of the invention,

Figure 3 illustrates a method according to a preferred embodiment of the invention, and

Figure 4 illustrates the control of the call according to a preferred embodiment of the invention. 4

The same reference numbers and markings are used for corresponding parts in the figures.

DETAD ED DESCRDPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

In the following, the operation of a system according to a preferred embodiment of the invention will be described briefly with reference to Figure 2. Fig. 2 shows the telephone 10a of a caller calling the service, a part of the Public Switched Telephone Network 20', an SSP 30, an SCP 40, which controls the SSP, IP devices 50a, 50b, 50c, switching points 25b, 25c of the Public Switched Telephone Network, which can also be SSPs, and other subscriber extensions 10b and 10c. It is assumed here that the caller selects a subscription number of the subscriber extension 10b. The call is directed via the telephone network 20', 30 to the exchange 25b of the subscriber extension 10b, or the point which controls the operation of the subscriber extension 10b. In accordance with the invention, at least one triggering condition has been saved in the information concerning the subscriber extension 10b of the exchange 25b, whereby the triggering condition determines whether the call is connected to the subscriber extension 10b, or the control of the call is transferred to the SCP 40. In order to implement such a triggering operation, the exchange must be provided with operations of an SSP or the like. A triggering condition like this can be one the following, for example:

- the control of all incoming calls is transferred to the SCP,

- if the extension is busy, the control of the incoming call is transferred to the SCP,

- if the extension does not answer, the control of the mcorning call is transferred to the SCP,

or some other triggering condition or a combination of triggering conditions. The service is then started with a triggering condition like this. It is assumed that in this case the triggering condition shows that the control of the call should be transferred to the SCP, and therefore the exchange 25b transfers the control of the call to the SCP. In accordance with the invention, the control rules of the voice service have been saved in the SCP 40. The SCP 40 recognizes the set of control rules of the required voice service preferably by means of a special voice service identifier, which is given by the exchange 25b. An identifier like this has preferably been saved among the information of the exchange 25b concerning the subscriber extension in question. The SCP can also use a B number, or a number selected by the caller as an identifier. The SCP controls a call transferred to it by the exchange 25b in accordance with control rules saved in the SCP.

The control rules saved in the SCP may include many different control functions. The control rules may control, for example,

- switching a call to the IP device,

- playing certain voice messages to the caller by means of an IP device,

- saving the caller's message by means of an IP device,

- switching the call to another subscriber extension, in the case of Fig. 2 to the subscriber extension 10c, for example,

- switching the call to the subscriber extension 10b, to which the call was originally made,

- switching a telephone call in accordance with special functions of the Intelligent Network, such as time, percentage or overflow control, or, for example,

- the change of the tariff charged from the caller in different stages of the call.

The control rules may also comprise other kinds of rules, such as rules dependent on time, by means of which a voice message service connected to the subscriber extension of a company's telephone exchange can be made to operate only outside the actual office hours, for example.

In this example, the SCP switches a call to the IP device 50a, 50b, 50c and directs the IP device to play the voice messages of the voice service wanted. In a solution according to the invention, the IP device serves the caller under the control of an SCP. The IP device can then repeat the voice messages wanted, receive selections made by the caller with the keypad of the telephone, or save the caller's messages, for example. The caller may also be given an opportunity to speak with an operator, whereupon the SCP 40 switches the call to a certain, predetermined subscriber extension 10b, 10c as a response to a certain number selection made by the caller.

As was mentioned above, the call may in this stage be connected in accordance with the special functions of the Intelligent Network, such as time, percentage or overflow control, for example. In time control, the call is connected to a certain number on the basis of a condition or conditions depending on the time of the day. In percentage control-, the call is connected with a certain first probability to a certain first number, with a certain second probability to a certain second number and so on. In this way, the mcoming calls can be distributed in the desired proportion to certain telephone numbers. In overflow control, the telephone call is connected according to a certain numbered list of telephone numbers to the first telephone number available. Because the service control point can control the connecting of the call entirely freely, connecting the call further does not leave the call going through a voice service device, like in the prior art solutions based on voice service equipment

According to the invention, the voice service can be implemented in connection with the desired subscriber extension in a simple manner

- by saving the control rules of the voice service in the call control point,

- by saving the voice messages of the voice service to the IP device, and

- by saving a triggering condition to the exchange of a subscriber extension for the subscriber extension in question.

By means of the arrangement according to the invention, a voice service can be implemented in connection with any subscriber extension, and the implementation of the service is not dependent on any service number series. The arrangement according to the invention also enables implementing the voice service with one IP device only, whereby it is easy to change and add voice messages, because it is not necessary to make the changes in a large number of IP devices, like in the prior art voice service systems, which use an Intelligent Network. In order to even out the telephone traffic, it is possible to use more than one IP device. There could be three IP devices in different parts of the country, for example. Then the SCP can connect the caller to the closest IP device, in which the voice messages of the voice service have been saved.

In the following, a preferred embodiment of the invention will be described with reference to the flow chart shown in Figure 3. Figure 3 illustrates the processing of a call coming to the subscriber extension 10b.

When a telephone call arrives at the exchange of a subscriber extension, the exchange checks 100 the triggering condition or conditions of the subscriber extension. If the triggering condition is not met, the process moves to step 120, in which the exchange connects the call to a subscriber extension, after which the processing of the method is stopped. If the triggering condition is met, and therefore the control of the mcoming call should be transferred to the SCP, the exchange transfers 130 the control of the call to the SCP. After this, the call is served 140 under the control of the SCP according to the predetermined control rules. When the call has been served according to the control rules, the processing of the method ends.

Fig. 4 illustrates some possible parts of step 140, or the call service step. However, this is only one possible example, because the structure .and control rules of the voice service can be implemented in many other ways as well. Therefore, Fig. 4 only illustrates some examples of possible functions.

According to the example of Fig. 4, at the beginning of the call service step 140, the SCP connects 200 the call to the IP device, and directs the IP device to play 205 a voice message to the caller. After this, the SCP directs the IP device to receive 210 the number selected by the caller. When the caller has selected a number, or a certain waiting time has passed without the caller's selection, the IP device transmits 215 information about this to the SCP. On the basis of the information received, the SCP directs the service of the call further. If the caller selected a number other than certain predetermined numbers, such as, in this example, other than number 1 or 2, or did not select any number, the SCP directs the IP device to give 220 an error announcement to the caller, after which the process returns to step 210, in which the SCP directs the IP device to receive 210 the number selected by the caller. If the caller selected number 1, the SCP directs the IP device to save 230 the caller's voice message, after which the call is disconnected 235 and the performance of the method ends. If the caller selected number 2, the SCP connects 240 the call to another telephone number or subscriber extension, such as an operator serving the callers, after which the performance of the method ends.

The call can also be connected to the same number which the caller originally called, i.e. the extension to which the voice service has been connected. The SCP can, for example, direct the exchange not to trigger the transfer of the call control, whereupon the call can be switched to a telephone of the extension in question. At another time like this, or when the call returns to the original number, it is also possible to consider different triggering conditions than at the first time of calling. For example, when the telephone is busy, the exchange may transfer the control of the call to the SCP again for extra service. Such second-time triggering conditions may advantageously be saved in the exchange in advance. 8

The invention provides many advantages. One advantage of the invention is the fact that it combines the best sides of both the voice automation solution and the Intelligent Network solution: quick and easy updating of the recordings and the possibility to use the versatile control functions of the Intelligent Network. In addition, the invention enables implementing the service entirely independent of the number, whereby the service can be connected to any subscriber extension. In comparison to earlier solutions in voice automation, in the solution according to the invention, connecting the telephone call further to other telephone numbers does not leave the call going through any voice automation server or the like, but the call is routed again via telephone exchanges. In addition, the solution according to the invention can be scaled well according to the service capacity required. When high service capacity is needed, more than one IP device can be connected to the system in order to serve a large number of callers. However, the system can also be implemented by means of one IP device.

The invention is not in any way limited to any certain property or properties of the telephone service, but all the different service forms supported by the Intelligent Network can be utilized in the voice service in different embodiments of the invention.

Although it was mentioned in the previous examples that the control rules of the services have been saved in the SCP, the control rules of the services can also be saved on a separate storage element, such as a special database. In a case like this, the SCP retrieves the control rules from the storage element, when required.

In the claims of this document, the term 'telephone exchange controlling a certain subscriber extensions' means an exchange according to the examples described above or a corresponding network element of the telephone network. Furthermore, the term 'device connected to the telephone network' used in the claims means an IP device mentioned in the examples above or a corresponding peripheral device of the telephone network.

The invention was described above with reference to some of its preferred embodiments, but obviously the invention can be modified in many ways according to the inventive idea defined by the attached claims.

Claims

1. A method for implementing a voice service in a Public Switched Telephone Network, characterised in that a telephone exchange controlling a certain subscriber extension transfers telephone calls coming to said subscriber extension under the control of the service control point on the basis of at least one triggering condition for implementing a voice service in connection with said certain subscriber extension.

2. A method according to Claim 1, characterised in that

- said telephone exchange receives a telephone call, which is addressed to a certain subscriber extension controlled by said telephone exchange,

- said telephone exchange checks whether the conditions set by said at least one rule are met, and if the conditions are met, said telephone exchange transfers the control of the call to the service control point.

3. A method according to Claim 1, characterised in that it comprises a step, in which said Service Control Point directs the call according to predeteτnined control rules.

4. A method according to Claim 1, characterised in that it comprises steps, in which

- the Service Control Point connects the call to a device connected to the telephone network,

- the Service Control Point gives the device a command to repeat a certain voice message,

- said device repeats said voice message as a response to receiving said command.

5. A method according to Claim 1, characterised in that it also comprises steps, in which

- the control point directs said device to receive numbers selected by the caller, and

-said device transmits the number selected by the caller to the control point.

6. A method according to Claim 1, characterised in that it also comprises a step, in which the control point directs said device to record the caller's speech.

7. A method according to Claim 1, characterised in that the control point connects the call to another subscriber extension.

8. A method according to Claim 1, characterised in that if said at least one triggering condition is not met, said telephone exchange directs the call to said subscriber extension.