GB2350258A

GB2350258A - Telecommunications networks

Info

Publication number: GB2350258A
Application number: GB9911448A
Authority: GB
Inventors: Brian E Collar
Original assignee: Telefonaktiebolaget LM Ericsson AB
Current assignee: Telefonaktiebolaget LM Ericsson AB
Priority date: 1999-05-17
Filing date: 1999-05-17
Publication date: 2000-11-22
Anticipated expiration: 2019-05-17
Also published as: GB9911448D0; GB2350258B

Abstract

A method of operating a telecommunications network comprises receiving from a calling party a call request which relates to a proposed call between the calling party and a called party and analysing the call request to detect whether calling line identity information corresponding to the calling party is available to the called party. If the calling line identity information is available, connecting the call to the called party. Or if the call request indicates that the calling line identity information is to be withheld from the called party, routing the call to an answering service. Or if the calling line identity information is unavailable, forwarding a call offer signal to the proposed called party.

Description

2350258 TELECOMMUNICATIONS NETWORKS The present invention relates to

telecommunications networks, and in particular to telecommunications networks in which calling line identity information can be transferred between calling and called parties.

DESCRIPTION AND RELATED ART

In conventional telecommunications networks which make use of calling line identity (CLI) information, calls on which the CLI information has been deliberately withheld (anonymous calls) can either be processed as normal calls or can be automatically rejected. This second option is commonly known as an anonymous call rejection service and is generally used when a caller has deliberately withheld the CLI information from the called party. It is used to prevent and deternuisance calls.

However, there are several disadvantages of the rejection service, such that there is no record of the call attempt available to the called party and as a result of simple rejection of the call there are no further processing options for the calling party.

SUMMARY OF THE PRESENT' INVENTION.

Embodiments of the present invention, therefore, aim to provide an enhanced anonymous call processing system, which can overcome the problems of the rejection service.

According to one aspect of the invention, there is provided a method of operating a telecommunications network wherein when a calling party withholds calling line identity information, calls requested by that calling party are directed to an answering service.

HL58154/000/CIV According to one aspect of the present invention there is provided an exchange apparatus for a telecommunications network, the apparatus comprising; call detection means which are operable to receive a call request from a calling party, which call request relates to an intended call between the calling party and an intended called party, the call detection means also being operable to produce a withholding signal if calling line identity information is withheld by the calling party; and call routing means connected to receive the withholding signal from the call detection means and operable to route the requested call to an answering service which is independent of the intended called party if such a withholding signal is received.

Accordingly, such a network can enable efficient handling of anonymous calls, whilst providing some call functionality for the caller.

BRIEF DESCRIPTION OF THE DRAWINGS.

Figure 1 is a schematic diagram of a telecommunications network; Figure 2 is a schematic diagram of an exchange unit used in the network of Figure 1; Figure 3 is a flowchart showing steps in the use of a system embodying the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Figure 1 illustrates a telecommunications network 1 in which a calling party 2 can place a call to a called party 3 by way of a telecommunications network 4 which includes network exchange apparatus 5. The calling party 2 communicates with the network exchange apparatus 5 by way of a first communications link 7, and the network exchange apparatus communicates with HL58154/000/CIV the called party 3 by way of a second link 9. Each calling party 2 and called party 3 has individual calling line identity (CLI) information associated with it so that each party can be identified, for example for billing purposes. The CLI information also enables the call to be correctly routed by the network 4 between the two parties 2,3. Depending on the type of telephone apparatus used by the called party 3, the CLI information of the calling party 2 may be displayed before the call is answered, or may be announced to the called party 3 (on request) if appropriate services are available on the subscriber's line. However, the calling party may withhold the CLI so that it is neither displayed nor announced to the called party 3.

A call is usually set up between the calling party 2 and the called party 3 through many nodes of the network 1. However, for simplicity, only one node, the network exchange apparatus 5, is shown in Figure 1.

The network exchange apparatus 5 is shown in more detail in Figure 2. The apparatus 5 includes a calling party receive means 10 which receives call requests and intended calls from the calling party 2. The exchange apparatus also includes call processing means 11 for routing calls to the appropriate destination, and CLI processing means 12 for controlling the call processing means 11 in dependence upon calling line identity information transmitted with a call request from the calling party 2, as will be described in more detail below.

The exchange apparatus 5 also includes answer service means 13, and ongoing call service transmit means 14. The transmit means 14 operates to connect HL581541000/CIV 4 the call to the intended called party 3 via the transmission line 9.

operation of the exchange apparatus shown in Figure 2 will now be described with reference to the f low chart of Figure 3.

The process starts at step A and at step B the calling party 2 initiates a call to the intended call party 3 by sending a call request signal to the network exchange apparatus 5. The network exchange apparatus 5 receives the call reques t, including call details, at the calling party receive means 10 (step C). The calling party receive means 10 transfers the calling line identifier information, or an indication that the CLI is unavailable or withheld, to the CLI processing is means 12. The remaining call request information which indicates amongst other things the proposed destination, to the call processing means 11.

The CLI processing means 12 examines the CLI information to determine whether the CLI information is available, withheld, or not available (Step D). If the CLI information is available, then the call is connected via the call processing means 11 and the ongoing call service transmit means 14 to the called party 3 by way of the transmission line 9. The CLI information is transferred to the called party 3 in the usual fashion.

The CLI information may be transferred to the called party 3 in known fashion, i.e. as a result of interrogating the exchange apparatus via transmission line 9 to obtain an audible indication of the last calling party CLI after the call or call attemt has been completed, (the UK 114711 service or equivalent) HL581541000/CIV Alternatively, the calling party CLI may be passed via transmission line 9, at the time the called party is alerted for display, in a visual format on equipment at the customer's premises (the UK Calling Number Display service or equivalent). The calling party CLI information provided by the called party's exchange apparatus will always be in the form of the standard international/national number, accompanied by the international/international prefix, thus providing a full diallable number allowing the called party to make a return call to the origianl calling party if this is required.

.The CLI information of the calling party is either generated wholly by the calling party's exchange apparatus or partly by the calling party and partly by the exchange apparatus. It is always accompanied by an indication as to whether or not the CLI is to be released to the called party, set under the control of the calling party. A further indication may also accompany the CLI, indicating whether or not the calling party has the ability to choose whether or not to inhibit display of his/her CLI. If this latter indicator is set to indicate that the option to choose is not available the CLI is deemed unavailable for display'. If it is set to indicate that the option to choose is available or the indicator is not received, then, if the CLI is marked as not for display to the called party,, it is deemed to be 'withheld from display'.

However, if the CLI is unavailable, or withheld, then the CLI processing means examines the CLI HL58154/000/CIV information further to determine whether the calling party is actively withholding the CLI information, or that the CLI information is simply not available due to network constraints. If the CLI is simply unavailable, then the call is offered to the called party (step J) which decides whether or not to accept or reject the call. In dependence upon the decision of the called party 3, the call is rejected or connected (step K).

If the called party is free the call is presented in the normal manner.by alerting the called party who may choose to answer or not to answer the incoming call, in conjunction with a Call Waiting service if this available. If the line is busy on another call or the called party does not answer the call within a is specified period, the call will be diverted to the answering service in the normal manner with an announcement to the effect that the called party is not available at this time' and a message may then be recorded.

The CLI information may be indicated as unavailable for a number of reasons. The full telephone number of the calling party may not be available due to signalling restrictions, the caller may not have the ability to withhold or release the CLI on a per-call basis, or the CLI may not be provided across network boundaries, for example because of the lack of bilateral agreements between service providers.

If the CLI information is found to be actively withheld by the calling party, then the call is automatically transferred to the answer service means 13 (step H), where the calling party is requested to leave a message for the called party. Thus, the HL581541000/CIV anonymous call is never connected to the called party 3 but to an answer service.

The network-based call answering service may be co-located at the called party's exchange, or at another remote point within the network. Where the answering service is situated at a remote location, then standard forwarding services are used to reroute calls from the called party's exchange to the remote platform. A suitable call forwarding service could be the standard 'Call Forwarding - Unconditional, Supplementary Service' ETSI Standard ETS 300 204 (1994-12). Whenever the received CLI information of the original calling party is determined by the called party's exchange apparatus to be 'withheld, then this service would be invoked to unconditionally divert the call to the remote answering service. This supplementary service has the ability to support transfer of the original calling party CLI information and the called (last diverting) party CLI information to the remote answering service.

The advantages of such a system include the fact that in some countries the majority of telesales calls have the CLI withheld.. Such calls can be received by the called party on a recorded message basis without sales pressure. In addition, call revenue can be increased as a result of increased network usage to the answering services and second calls made by calling parties who are subsequently prepared to release their CLI information. Also, the service provides a track of anonymous calls which is of some use when trying to trace malicious calls. Malicious calls invariably have CLI information withheld, and so potential called HL581541000/CIV parties would not be concerned by "live" abuse, threats or silence and any recorded messages can be ignored or might provide useful evidence on caller identity.

In a preferred enhancement to such a system, the answering service can be turned on or off by the called party concerned, and also the announcement which is relayed to anonymous callers can be customised. In addition, retrieval of anonymous call messages could. be controlled by the called party. For example, the party could be informedimmediately of a message by a call from the answering service, or could be informed only by a message waiting indication. To provide the called party with a 'message waiting indication' that a message has been left -by a calling party who has withheld his CLI, a distinctive dial tone may be temporarily connected to the called party when she/he next lifts her/his receiver. This could be distinct from the current message waiting indication' dial tone connected whenever a message is left as a result of the called party being absent (unanswered call). The connection of the distinctive dial tone at the called party's exchange apparatus would be achieved by a special 'transaction, call made automatically from the call answering service to the called party's exchange apparatus in a similar manner used to connect the existing message waiting indication,.

HL581541000/CIV

Claims

CLAIMS:

1. A method of operating a telecommunications network wherein when a calling party withholds calling line identity information, calls requested by that calling party are directed to an answering service.

2. A method of operating a telecommunications network, comprising receiving from a calling party a call request which relates to a proposed call between the calling party and a called party; analysing the call request to detect whether calling line identity information corresponding to the calling party is available to the called party; and if the calling line identity information is is available, connecting the call to the called party; or if the call request indicates that the calling line identity information is to be withheld from the called party, routing the call to an answering service; or if the calling line identity information is unavailable, forwarding a call offer signal to the proposed called party.

3. A method as 'claimed in claim 2, wherein, on receipt of such a call offer signal, the called party can accept or reject the proposed call.

4. Telecommunications network apparatus comprising means for routing call requests to an answering service when the calling party making the request withholds calling line identity information.

5. A telecommunications network comprising; means for receiving a call request from a calling party, the call request relating to a proposed HL581541000/CIV call between the calling party and a called party; detection means for analysing the call request to detect whether calling line identity information relating to the calling party is available to the called party; connection means for connecting the call to the called party if the calling line -identity information is available to the called party, answering means for routing the call to an answering service if the call request indicates that the calling line identity information is to be withheld from the called party, and processing means for offering the call to the called party if the call request indicates that the calling line identity information is unavailable to the called party.

6. A network as claimed in claim 5, wherein the processing means include means for receiving an accept signal from the called party, and for connecting the call to the called party in response to receipt of an accept signal.

7. A network as claimed in claim 5 or 6, wherein the processing means include means for receiving a reject signal from the called party, and for rejecting the call request in response to receipt of an reject signal.

8. A network as claimed in claim 5, 6 or 7, comprising an answering service means operable to record incoming messages from a calling party.

9. A method of operating a telecommunications network, substantially as hereinbefore described with reference to the accompanying -drawings.

10-

10. A telecommunications network substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.

HL5815410001CIV

9. Node apparatus for a telecommunications network, the apparatus comprising; means for receiving a call request from a HL581541000/CIV calling party, the call request relating to a proposed call between the calling party and a called party; detection means for analysing the call request to detect whether calling line identity information relating to the calling party is available to the called party; connection means for connecting the call to the called party if the calling line identity information is available to the called party, answering means for routing the call to an answering service if the call request indicates that the calling line identity information is to be withheld from the called party, and processing means for offering the call to the is called party if the call request indicates that the calling line identity information is unavailable to the called party.

10. Node apparatus as claimed in claim 9, comprising answering service means operable to record an incoming message from a calling party.

11. A method of operating a telecommunications network, substantially as hereinbefore described with reference to the accompanying drawings.

12. A telecommunications network substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.

HL581541000/C1V Amendments to the claims have been filed as follows i 2_ CLAIMS:

1. A method of operating a telecommunications network, comprising:

receiving from a calling party a call request which relates to a proposed call between the calling party and a called party; analysing the call request to detect whether calling line identity information corresponding to the calling party is available to-the called party; and if the calling line identity information is available, connecting the call to the called party; or if the call request indicates that the calling line identity information is to be withheld from the called party, routing the call to an answering is service; or if the calling line identity information is unavailable, forwarding a call offer signal to the proposed called party.

2. A method as claimed in claim 1, wherein, on receipt of such a call offer signal, the called party can accept or reje ct the proposed call.

3. A telecommunications network comprising; means for receiving a call request from a calling party, the call request relating to a proposed call between the calling party and a called party; detection means for analysing the call request to detect whether calling line identity information relating to the calling party is available to the called party; connection means for connecting the call to the called party if the calling line identity information is available to the ca lled party, answering means for routing the call.to an answering service if the call r equest indicates that the calling line identity information is to be withheld BW81541000/CM f rom the called party, and processing means for offering the call to the called party if the call request indicated that the calling line identity information is unavailable to the called party.

4. A network as claimed in claim 3, wherein the processing means include means for receiving an accept signal from the called party, and for connecting the call to the called party in response to receipt of an accept signal.

5. A network as claimed in claim 3 or 4, wherein the processing means include means for receiving a reject signal from the called party, and for rejecting the call request in response to receipt of an reject signal.

- 6. A network as claimed in claim 3, 4 or 5, comprising an answering service means operable to record incoming messages from a calling party.

7. Node apparatus for a telecommunications network, the apparatus comprising; means for receiving a call request from a calling party, the call request relating to a proposed call between the calling party and a called party; detection means for analysing the call request to detect whether calling line identity information relating to the calling party is available to the called party; connection means for connecting the call to the called party if the calling line identity information is available to the called party, answering means for routing the call to an answering servic.e if the call request indicates that the calling line identity information is to be withheld from the called party, and -3 5 processi. ng means for offering the call to the 111.581541000/CIV - Itt. - called party if the call request indicates that the calling line identity information is unavailable to the called party..

8. Node apparatus as claimed in claim 7, comprising answering service means operable to record an incoming message from a calling party.