AU4752699A

AU4752699A - ISDN/IN interaction for bearer-unrelated applications

Info

Publication number: AU4752699A
Application number: AU47526/99A
Authority: AU
Inventors: Rainer Munch; Thilo Webel
Original assignee: Alcatel CIT SA; Alcatel SA
Current assignee: Alcatel Lucent SAS
Priority date: 1998-09-14
Filing date: 1999-09-10
Publication date: 2000-03-23
Also published as: DE19841926A1; EP0987908A2

Description

P/00/01 1 Regulation 3.2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE

SPECIFICATION

STANDARD

PATENT

'ISDNIIN interaction for bearer-unrelated applications' *fee 0.04e statement is a full description of this invention, including the best rforming it known to us: R4PSYFlCERNAT1Cfl2flAQq253flI 5.9 ISDN/IN Interaction for Bearer-Unrelated Applications Field of the invention The invention relates to a process for making available a ISDN/IN interaction function for bearer-unrelated services in a communications network environment.

Background of the invention Bearer-unrelated applications are applications which do not relate to a bearer channel.

Their opposite are bearer-related applications which include in particular the transmission of telephone conversations between two subscribers of a public telephone network via a bearer channel of this telephone network. A bearer-unrelated application i 10 is for example the service CCBS (completion of calls to busy subscribers). These bearer-unrelated applications are transmitted exclusively in the signalling channel.

,In a network environment comprising a plurality of competing network operators in which number conversion is required subscriber number portability, IN-services), °0 an IN-function is also to be used for bearer-unrelated services, for example ISDN 15 service features (ISDN supplementary services). To be able to user a server based on an IN (intelligent network) for this task, it is necessary to define an interaction between SSPs (service switching points) of the IN and SCPs (service control points) of the IN which permits the function of the IN-server to be applied to such service messages.

In ITU-T SG 11, the company Ericsson proposes an ISDN-IN coupling on the TC-level (TC transaction capability, transaction control section, i.e. a functional block of the ITU-T Signalling System No. 7 (SS No. The SS No. 7 layers are processed in the SSP up to and including the TC layer. The complete contents of the TC messages are sent from the SSP to the SCP. The SCP performs an analysis of the messages and determines which function is to be executed.

Summary of the invention According to a first aspect of the present invention there is provided a process for making available a ISDN/IN interaction function for bearer-unrelated services in a communications network environment, wherein: -messages of bearer-unrelated services are transferred to a service switching point; -the service switching point analyses these received messages; -by means of this analysis the service switching point determines whether a service control point must be invoked to make available functions for these messages assigned to bearer-unrelated services and which information is sent to the SCP.

The invention may relieve the load on the SCP, which may be advantageous in particular in view of a likely increase in telecommunications subscribers with number portability, and to facilitate a service-specific division of functions between SSP and

SCP.

10 This approach thus provides a ISDN-IN coupling at the application level. ISDN .messages and SS No. 7 messages are analyzed by the SSP in the application level. By means of this analysis the SSP decides whether it needs to switch on the SCP for this message or not and which information is transmitted to the SCP.

An advantage of the invention in the case of those decisions in which the SSP can S 15 ascertain beyond doubt that for example number portability is not provided, the SCP can be freed of a decision to this effect, whereby the capacity of the SCP is available for **other tasks.

Further advantages of the invention consist in a substantial reduction in the number of invocations of the SCP (or the SCPs of the network). When a SCP invocation is necessary, less data need be transmitted. It is also advantageous that the signalling traffic between SCP and SSP is reduced, that it is consequently faster, and that less data processing capacity is required in the SCP. Finally it is advantageous that the SCPs need be less complex since the application level does not require to be understood or to be completely understood.

There are two possibilities of mapping bearer-unrelated services onto IN services.

1)A service-specific INAP invocation which controls a service-specific IN service is defined for each type of bearer-unrelated services.

2)All bearer-unrelated services are handled by one single IN service. Within the INAP invocation for this service, data relating to the type of service and service parameters are transported to the SCP.

In particular, in an embodiment of the invention the SSP can itself decide that number portability is not required if the type of service requested by a subscriber does not relate in some way to another subscriber. Such messages, which do not relate to another subscriber, consist for example of a time announcement or the switch-over of the terminal of the subscriber issuing the instruction to a call answering function or mailbox function provided in the telecommunications network.

10 It is considered to fall within the scope of the invention that the requests for those services in the case of which it is not possible easily to decide in the above described •manner whether number conversion is required or not, are forwarded by the SSP to the SCP for a decision. Preferably however, the telecommunications network is designed such that the SSP assigned to the subscriber requesting the service itself makes a S• 15 decision whether subscriber number portability is to be made available or not for a bearer-unrelated service and which information is sent to the SCP. The advantage here consists in that the SCP is completely freed of such decisions, which also results in the fact that the SCP can be designed to be technically simpler or that its technical devices are available for other services and activities.

2 0 According to a second aspect of the present invention there is provided a service switching point, comprising a device for analyzing messages of bearer-unrelated services, said device being designed such that it analyzes such received messages and by means of this analysis determines whether a service control point must be invoked to make available functions for these messages assigned to bearer-unrelated services and which information is sent to the service control point.

The invention also relates to a SSP which is designed, in accordance with the invention, such that it comprises a device for analyzing service requests of a subscriber, where this analysis consists in deciding whether a bearer-unrelated service requested by a subscriber necessitates a number conversion or not. If the SSP ascertains that for example number portability is not provided, the request for this service is not forwarded to the assigned SCP and instead the SSP itself initiates the execution of the service.

According to a third aspect of the present invention there is provided a service control point wherein at the request of a service switching point it makes available subscriber number portability functions for messages of bearer-unrelated services.

The invention also relates to a SCP which is designed, in accordance with the invention, in that it comprises no or limited devices for checking whether a requested number conversion is necessary, and comprises only devices for making available a requested number conversion. The aforementioned checking is not necessary as it is performed in 10 a lower level by the SSP.

•The invention also relates to a SCP which is designed, in accordance with the invention, in that it makes available only limited devices of a specified ISDN service or facility.

Brief description of the drawings Further features and advantages of the invention will be set forth in the following S 15 description of exemplary embodiments of the invention making reference to the drawing, which illustrates details essential to the invention, and in the claims. The individual features can be implemented individually or jointly in arbitrary combinations in an embodiment of the invention. In the drawing:

*O

Figure 1 is a schematic representation of a fundamental network configuration; Figure 2 is a schematic representation of the function sequence in the SSP.

Detailed description of the embodiments In accordance with Figure 1, a calling subscriber A is connected to its exchange, the originating exchange 1. The conversation is conducted via a transit exchange 2 (or in other configurations via a gateway exchange) to an exchange 3, which in this example performs the function of the SSP. From the SSP the connection passes via a further transit exchange 2' to the destination exchange 4 and from there to the called subscriber

B.

The SSP is connected to a SCP which normally will not be situated in the vicinity of the

SSP.

In the following text, the following abbreviations with the following meanings will be used: CCF (call control function); Sy is a part of the nodal application process (exchange application process) for the service Y; Sx is a part of the nodal application process for the service X; SSF (IN service switching function); MTP (message transfer part); SCCP (signalling connection control part); INAP (intelligent networks application protocol); TC (transaction capability); MPT, SCCP and TC are functional blocks of the ITU- 10 Tsignalling system No. 7.

Figure 2 does not represent a circuit diagram, but rather the functions taking place in the SSP. A message incoming into the SSP enters from the bottom left of Figure 2. This message is transported via the MTP, as is generally the case. The MPT message contains a SCCP message which is processed in such manner that the TC part is obtained therefrom.

The task of the coordination function is to transfer the content of the TC message to the o corresponding protocol section in the exchange in the SSP which is responsible for the service X, by which it is analyzed in accordance with protocol technology. This service -X is a bearer-unrelated application, in the example CCBS. Other services not relevant 20 to the invention may also be active, as expressed by the box Service Y In terms of logic (not in terms of circuitry), the result of this coordination function is transferred to the corresponding functional handling components, which is generally referred to as nodal application process. The nodal application process basically consists of CCF, SSF, and service-specific components, expressed by Sx, Sy, although other functions can also occur. The task in particular of the three blocks CCF, Sx, SSF, is now to carry out the required analyses and make the correct decisions. CCF activates the service Sx and makes available general exchange resources. From CCF and Sx the SSF receives the activation criteria for the IN control and initiates the transmission of a INAP message to the SCP. For this purpose the result of the nodal application process is then transferred to the coordination box on the right-hand side of Figure 2. This causes a corresponding INAP message to be prepared in accordance with protocol technology, which is then transferred into a TC message. This TC message is passed to the SCCP which itself performs its protocol technology functions. The said message is then transferred to the MTP. Now the message is ready to be send to the SCP. This message is then analyzed by the SCP. The "coordination" boxes shown in the drawing carry out a time coordination and flow control.

SSP and SCP are described for example in ITU-T Recommendation 1214.

It should be noted that where in the specification or claims the term "comprising" is used that term should be interpreted inclusively rather than exclusively.

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Claims

1. A process for making available a ISDN/IN interaction function for bearer-unrelated services in a communications network environment, wherein: -messages of bearer-unrelated services are transferred to a service switching point; -the service switching point analyses these received messages; -by means of this analysis the service switching point determines whether a service control point must be invoked to make available functions for these messages assigned to bearer-unrelated services and which information is sent to the service control point. 10

2. A process according to Claim 1, wherein the analysis takes place on the protocol application level.

3. A process according to Claim 1 or 2, wherein the service control point provides functions for making available subscriber number portability for messages of bearer- unrelated services.

4. A service switching point, comprising a device for analyzing messages of bearer- unrelated services, said device being designed such that it analyzes such received messages and by means of this analysis determines whether a service control point must be invoked to make available functions for these messages assigned to bearer- unrelated services and which information is sent to the service control point.

5. A service control point, wherein at the request of a service switching point it makes available subscriber number portability functions for messages of bearer-unrelated services.

6. A service control point according to Claim 5, characterised in that it comprises no or limited devices for checking whether a requested number conversion is required, but only comprises devices for making available a requested number conversion.

7. A service control point according to Claim 5 or 6, characterised in that it only makes available limited devices of a specific ISDN service or facility.

8. A process substantially as hereinbefore described with reference to the accompanying drawings.

9. A service switching point substantially as hereinbefore described with reference to the accompanying drawings.

10. A service control point substantially as hereinbefore described with reference to the accompanying drawings. Dated this 10th day of September 1999 ALCATEL by its attorneys Freehills Patent Attorneys *oe