GB2409947A

GB2409947A - Telephone security service

Info

Publication number: GB2409947A
Application number: GB0400455A
Authority: GB
Inventors: Alan Neil Hixon
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-01-09
Filing date: 2004-01-09
Publication date: 2005-07-13
Also published as: GB0400455D0; GB0402915D0

Abstract

A telephone security service that allows a user or subscriber (the user) to control whether or not to accept a call from a caller (the caller). The service identifies the caller to the user by reciting a voice, word, data or image tag for the caller prior to putting the call through to the user. The user can then decide whether to take the call. The tag for the caller is identified for the caller from a PIN entered by the caller when the caller called the service.

Description

1 2409947 Telephone security service The present invention relates to a

telephone security service that allows a user or subscriber (the user) to control whether or not to accept a call from a caller (the caller). The service identifies the caller to the user prior to putting the call through to the user.

Normal incoming telephone calls can be recognised using "caller ID", a service provided by most telephone networks. However, a caller can withhold his caller ID. It would therefore be desirable to provide a service that can enable a user to identify a caller before taking a call from the caller, or to filter unwanted calls, irrespective of whether the caller withholds his caller ID.

Various services have been set up to filter calls. For example, US Patent No. 6,553,115 discloses a telephone call filtering service using a service number and a Personal Identification Number (PIN) for enabling a caller to access the service only if he has a valid PIN. However, if the caller ID is withheld, the service customer will not be able to tell who the caller is. Additionally the administration of the multiple PlNs that need to be set up with this system is difficult unless the customer keeps records of to whom he gave PINs. It also limits the subscriber's ability to screen in-coming calls effectively because the caller could enter the PIN but still withhold their telephone number.

US Patent No. 4,446,334 also discloses a means for call filtering. It comprising a device that is positioned between a telephone jack and a telephone. It is limited in its use, however, since it will store only one PIN at a time. If that PIN is included with the number dialled by the caller, the filter will allow the call to go through and the telephone to ring.

US Patent No. 4,313,035 also discloses a call filtering system. Its primary use is with dating services where the dialling of a central number, together with a PIN, allows a call to be made to a given or userselected target telephone without the caller knowing the telephone number of the target.

US Patent Application No. 2002/0041664 also discloses a call filtering system. It looks for a caller ID signal, and if one is not present, an audible caller identification is requested from the caller before the call is connected to the target telephone. The system, however, can be bypassed by the caller if he has a PIN for that purpose. The call, if accompanied with a PIN, is connected directly to the target number. If the caller ID is withheld, however, the identity of the caller could still remain unknown to the subscriber.

Despite these known services and devices, it would still be desirable to provide a service that enables both filtering of calls and identification of callers irrespective of whether the caller withholds their caller ID. A system for the management of PINs would also be desirable.

The present invention provides a telephone security service comprising: a service number for a user or subscriber, retained by a service provider, the service number being the number that the user or subscriber can give to prospective callers for contacting the user or subscriber via the service, a target number nor the user or subscriber for the service provider to call upon receiving a call on the service number from the prospective caller; a PIN for that caller, the PIN being required to be given to the service provider by the caller calling the service number before the caller's call can be connected or re-directed to the target number; and a tag for the caller to identify the caller, the tag being associated with the PIN by the service so that upon receipt of the PIN Prom the caller, the service can identify the caller, the tag not being the caller's caller ID; wherein, before re-directing a call from a caller to the target number, the service provides information concerning the tag for the PIN to the user or subscriber, or the target telephone of the user or subscriber, to give the user or subscriber, or the target telephone, the option to decide whether to take the call.

The service can be used with existing telephones, which telephones can still be called normally by dialling the target number directly, or with service specific telephones, i.e. telephones not having a different target number to the service number.

Preferably the service number is different to the target number. However, if the service number is the same as the target number, calls to the service number not accompanied by a PIN or having an invalid PIN may be directed straightaway to a voicemail system. The voicemail system may be one provided by the service. The service may alternatively be set up such that when the service number is the same as the target number, calls to the service number not accompanied by a PIN or having an invalid PIN are not connected to the target number at all.

Preferably the user or subscriber provides the tag for identifying the caller. The tag may be the caller's name or a nickname. The tag is preferably a voice tag. However, it may be a word or data tag for transmitting to the target telephone, mimicking a caller ID service. Yet further, the tag may be an image tag, such as a video clip or a still image.

Preferably the user or subscriber provides the PIN.

Preferably the service number is unique to the user or subscriber. Preferably the user or subscriber has just one service number.

Preferably the target number can be selected by the user or subscriber from any one of his own personal or business telephone or pager numbers.

The service may pass on caller ID information to the target telephone if the caller has not withheld his caller ID signal.

The service provider may be a call centre administered by a communications network or software implemented on a communications network. The service provider might alternatively be a program retained in a telephone handset or in a company's telephone network.

The present invention can be used with cell phones, i.e. mobile phones, or conventional landlines.

Preferably the user or subscriber can interact with the service provider to set up new PlNs for new callers so that the service provider can identify the new callers from the new PlNs.

Preferably the user or subscriber may perform the setting up of the service by keying in details on his handset. Alternatively, the interaction is by vocal means, for example by talking to an operator at a call centre, or using voice recognition software on the handset or at the call centre. s

Voice tags may be set up by recording them for any new PIN or caller by speaking into the handset of a telephone.

Image tags may be set up, for example, by transmitting a link to an image or video file, or by picture or video messaging.

Preferably multiple callers can be set up on the system, each with their own unique PIN and tag.

Groups of callers may be set up, the callers in each group sharing the same PIN.

Preferably PlNs can be cancelled or suspended to prevent the callers associated with those PINs from calling the user or subscriber either permanently or temporarily.

Preferably the service provider will be able to upload PIN, caller and tag information (the service records) onto a database accessible via the internet or via an interactive handset, such as a WAP phone or handheld PC, for maintenance or administration of the service records by the user or subscriber on the internet or via the handset.

Preferably the service is adapted to recognise the PIN from a dialled number, where the PIN is attached to that dialled number at the end of the service number. The PIN may be separated from the service number by an appropriate command character, such as the "#" or pound sign. With this system, the caller will be able to store the service number and PIN in their telephone's phonebook for automated dialling of the service number and then the PIN by the telephone. The caller then will not need to remember the numbers.

Preferably the service can be set up to filter calls selectively. For example it may filter calls at certain times. Alternatively it may filter calls by filtering certain callers from the service via the PINs used by callers. In this manner, the user or subscriber can avoid calls from certain people and/or at certain times.

Preferably the service can be set up to use a different target number at different times of the day, week or year. This enables a user or subscriber, for example, to have his work number dialled during the day, his home number dialled in the evening and his mobile phone dialled during his annual leave.

The service may also be set up to transfer all or selected callers direct to voicemail at certain times of day, week or year.

Preferably the service checks incoming calls for caller IDs. The caller ID may be useful for checking the identity of callers or for deciding whether to accept the call. For example, the service could filter out all calls that exclude a caller ID, or just filter out those calls for certain PINs.

A preferred embodiment of the present invention, and various further optional features, will now be described, by way of example only.

Figure 1 schematically shows the three elements of the telephone security service of the present invention; and Figure 2 shows a flow chart for a preferred embodiment of the present invention.

The present invention is a telephone security service that can be used by a user or a subscriber 14. From now, the user or subscriber will be referred to as the user 14.

The user 14 gives out a telephone number (the service number, which is generally not the target number or actual number for the telephone) for contacting him, or one of his telephones, to a prospective caller 10. He additionally gives the caller a Personal Identification Number (the PIN). The service number is one that will only operate, i.e. call the user 14 or his telephone, if the caller 10, upon ringing the service number, additionally enters the PIN that he was given for the service number.

Before the PIN will work, the user 14 additionally needs to set up that PIN for the caller 10. In order to set up the PIN for that particular caller 10, the user 14 contacts or interacts with the service provider and sets up the service for that PIN so that the service provider can identify the caller 10 from the PIN and service number combination. Once this has been done, whenever the caller 10 rings the service number and additionally provides the PIN, while the PIN is valid the service will accept calls from that caller 10 and offer the call to the user 14.

If more than one caller 10 is to be set up for using the service for that service number, each caller 10 can be allocated a different PIN. The user 14 then sets up the allocated PIN for that new caller 10 with his service provider. The various callers can then be distinguished from each other by their respective PINs.

The user 14 can set up new or additional PlNs for callers by calling the service provider and entering commands via a touch-tone telephone. The user 14 can have the option to choose the PIN or have the system generate a random PIN. If the subscriber chooses the PIN, it must not be one already in use for their service or one that has been previously used and cancelled or deleted, unless the service is adapted to allow the re-use of cancelled or deleted PINs.

When setting up a PIN for a caller 10, the user 14 will be prompted to record a tag for that caller 10. The tag is normally a voice tag. However it might be a word, data or image tag.

Word or data tags can potentially be set up by the user 14 by tenting the PIN and word or data tag to the service provider or by typing it directly into the phone at the prompt.

The tag will represent the name or identity of the caller 10 (or group of callers if the same PIN is given to more than one person, such as a business or company). The PIN is uniquely associated by the service with the tag so that once the service has identified the caller 10 upon receiving the PIN from the caller 10, the service will know the tag for that caller 10.

The user 14 will occasionally find a need to administer the PlNs and tags set up for his service. In a suitably adapted system, this can be done on the telephone or via the internet.

During administration of their PTNs list, the user 14 can listen to, look at or otherwise review the recorded tags for their PINs and retain required callers or cancel, i.e. delete, unwanted callers from their list.

If, after extensive use of the service, a user 14 finds that they have insufficient PINs available for adding new callers to their service, they can request a batch of cancelled or deleted PINs to be re-activated.

Any telephone having an existing number (a target number) can be converted to use the service of the present invention. This can be with the existing number for that telephone being set up as the service number for giving to the caller 10. The target number will then be the same as the service number and the telephone will only be able to be called via the service. Alternatively, and more usually, the service number given to the caller 10 will be a number specifically allocated or chosen by either the service provider or the user 14 for using the service, and not the target or actual telephone number for that telephone.

In the preferred embodiment, however, the service number is a different number to the target number, i.e. the number used for normally calling that telephone, i.e. without using the service. With the preferred embodiment, the user 14 can choose whether to give a caller 10 a conventional caller access number for calling him directly or a number for calling him only via the service. The decision might be made dependent upon the relationship between the user 14 and the caller 10.

The user 14 will have set up his service such that the service will associate the service number with the target number so that it can ring the target number upon receiving a call via the service number from a caller 10.

The user 14 can operate multiple telephones with the service. For example, the user 14 can set up multiple target numbers with the service provider. Then, he can have a default number, or a specified nurnbcr, which can be changed at will by the user 14 depending upon where he is, which the service calls upon receiving a call on the service number. For example, the default number might be set up to be one number - his work number - at certain times of the day, such as working hours, and another number - his home number at other times of the day, such as the late afternoon and early morning. A third default number might also be provided, perhaps at night-time, which number might be connected directly to an answer phone.

Generally, however, the target number will be set by the user 14 to be the telephone to which he will be closest to.

The service can be programmed or set up by the user 14 for ringing any telephone or number already in use by him that has been registered with the service provider by the user 14. In fact, the user 14 can set it up for any target number of choice. For example, the target number might be someone else's number, such as a work colleague's number. This could be useful if the user 14 is temporarily unavailable, but requiring personal service, rather than an answer phone service. Also, different target numbers may be set up for different callers so that the service will phone the user 14 for one particular caller 10 or set of callers, but a different number for other callers.

When the service has received a call comprising both the service number and a valid PIN, the service will recognise the caller 10 from the PIN. Additionally, this identity can be cross-checked if the caller 10 has not withheld his caller ID and has previously called from that telephone, or if the user 14 has provided that caller ID information to the service provider. The service provider will also be able to determine which user 14 the caller 10 is trying to call by reference to the dialled service number. Once the service has identified both the caller 10 and the intended user 14, the service will call the appropriate target number and inform the user 14 or target telephone of the caller's identity to give the user 14 or the telephone the chance to decide whether to accept the call. If the call is accepted, the caller's call is redirected to the target number.

The service can identify the caller's identity to the user 14 by reciting the tag to the user 14 as a voice message or a visual message. For example, if the voice tag is simply the caller's name, the service may audibly announce the call by announcing to the user 14 "'John Smith' is calling". Alternatively, with word, data or image tags, and/or if there is a caller ID signal from the caller 10, the service can display the word, data or image tag, and/or the caller ID, on the target telephone.

The voice tag and/or the word, data or image tag may be announced or displayed in addition to the caller ID being displayed. This will assist the user 14 to confirm the identity of the caller 10. The user 14 can then decide on the basis of the given identity of the caller 10 whether to accept the call or take some other action, like refuse the call or pass the call to voicemail. As an example, pressing I might accept the call, pressing 2 might reject the call and pressing 3 might direct the call to voicemail.

Due to the use of the PIN and the tag, the service of the invention enables the user 14 to have the identity of a caller 10 revealed to him before he takes the call, irrespective of whether the caller 10 has withheld his caller ID.

With the service, the caller 10 need not be informed of the user's decision. For example, while the caller's identity is being announced to the user 14, the caller 10 could be kept unaware that the call is being announced for example by continuing to play a ringing tone in the caller's telephone handset until the call is accepted, rejected or diverted to voice mail.

Sometimes the call will simply not be answered. The service can be set up such that such a no-answer can default to an answer phone after a number of rings. Alternatively the service can simply keep ringing until the network terminates the call.

If the call is rejected by the user 14, the service may default to divert the call to the service's own voicemail. To keep the caller 10 unaware of the user's decision to reject the call, for example so as to avoid insulting the caller 10, the service could allow the caller 10 to hear the same number of "rings' before it is diverted to that voicemail whether the call was rejected or not answered.

If the target number is a landline having an answer phone connected to it, the answer phone may cut in before the user 14 answers the call. If the service calls that telephone in response to a call from a caller 10, the service will not receive a selection from the user 14 if the answer phone cuts in. The service could then default to its own answer phone or voicemail, rather than the target telephone's answer phone or voicemail.

The caller 10 will need to track or record the PINs that they have been given so that they will be able to use the service. In order to keep a record of the PIN, callers can enter the PIN into their telephone's phonebook by storing the service number, followed by, for example, the "#" sign and then the PIN. The service can be set up to recognise the PIN from such a dialled number. This will therefore allow the caller 10 to call the service number and automatically have their phone dial the PIN for them as well. The caller 10 thereby won't have to remember the PIN.

The user 14 can set up their system to divert calls automatically to voicemail during certain times or for certain callers, as recognised from the PINs, such as during business hours, Monday to Friday. This would be useful if the user 14 does not want to be disturbed by the caller 10 or callers at those times. The user 14 could perhaps do this by interacting with the service provider and relaying commands to the service provider through touch-tones, i.e the handset of the telephone, or via the internet. Such commands could include time or day restrictions by entering the hours during which calls should or should not be received (e. g. 09001700, for 9AM to 5PM) and the days on which they should or should not be received (e.g. 15, for Monday to Friday).

When the user 14 no longer wishes to receive calls from a person or group associated with a particular PIN, they can cancel or delete the PIN. When the PIN is cancelled or deleted, the caller 10, upon trying to use the service, hears a message informing them that their PIN has been cancelled. They will thereafter not be able to contact the user 14 using the service number until they obtain a new, valid, PIN.

If the user 14 thinks that a PIN used for a particular person or a group of callers (e.g. a company or a group consisting of friends or family members) has been discovered by an unwanted caller, they can suspend the PIN. When the PIN is suspended, all calls using that PIN are directed to voice mail. The user 14 is then able to create a new PIN for that person or group and inform the caller 10 or callers in the group. The user 14 could then leave the PIN as suspended and continue to pick up messages from callers that have not been given the new PIN. It could be that voice messages from a suspended PIN are preceded by an announcement such as "Suspended PIN" to remind the user 14 to forward the new PIN to the caller 10 that left the message.

The service may also be set up to block all calls from certain callers, as recognised from the PINs, that have their caller ID withheld.

If an existing telephone number is converted for use with the service of the present invention, to avoid the need to provide PINs for all callers, the user 14 can have the option to have all calls omitting a valid PIN diverted to voicemail. The subscriber can then choose to disable this option at some time in the future, for example if they feel that all likely callers required for that number have been allocated a PIN.

If there are repeated attempts by a caller 10 to guess an active PIN, the service could be set up to inform the user 14. The service could then offer the user 14 a new service number.

Service providers for the service of the present invention are most likely to be large voice communication carriers. Such companies include Verizon, Cingular, MCI and AT&T.

They are likely to be quick to implement the service of the present invention because they have existing infrastructure for operating the service. They can direct calls using the service to a telephone number that they have already provided to the user 14. This will have the benefit of avoiding call-forwarding charges that might otherwise be incurred as a result of the re-directing of calls provided by the service. If the user 14 chooses to forward the call to a target number that is reserved for or used by a different voice communication carrier to the one operating the service, then there might be a charge for the call forwarding. Likewise, if an independent party (i.e. not an existing voice communications carrier) provides the service, all received calls will be for the service and will need to be forwarded to the user 14 on a voice communication carrier's network.

Although these are potential costs, those costs can be passed on to the user 14. As a result of this, the present invention provides serviceproviding companies with a means for obtaining revenue.

Instead of the communications carrier operating the service, as previously indicated the service provider may be a program incorporated into a handset. Modern telephone handsets, or office phone networks, can transfer and redirect calls themselves. If this is implemented, then the cost of adding the service to a handset might then be recovered from revenue arising from sales of the handsets, or in the fee for using those handsets, as opposed to handsets that cannot operate the service, on a phone network.

The present invention also has many uses: Dating: one problematic issue when meeting new people or when using a dating agency is the risk associated with giving out a private telephone number. A PIN could be created for any or each prospective date and then cancelled when or if the user 14 no longer wants to be contacted by the date. A PIN could, for example, be created by the user 14 by calling the service provider or by texting the PIN to the service provider with the name of the date after first meeting the date.

Ex partners: where children are involved, it's not uncommon to have to give ex partners a contact telephone number so that they can maintain contact with their children. However, the use of the number can be abused, for example if the ex partner gets upset with the other parent or the guardian of the children. For example there may be offensive phone calls.

The service of the present invention, however, allows the user 14 to cancel or suspend the PIN of the ex partner in such circumstances and only to issue a new one or restore the old one to service when the ex partner returns to an acceptable state of mind to resume contact with the children.

Business numbers: if a private telephone such as a cell phone or mobile phone is also used for business calls, the user 14 could set up a generic "business PIN" so that business calls are automatically diverted to voicemail outside of certain times.

Sales call: if a salesperson requests a contact number, a service number and PIN can be provided to that salesperson. The PIN can then be cancelled later if the user 14 no longer wishes to be contacted by the salesperson.

Items for sale: when advertising goods for sale, a PIN can be created for that transaction and then cancelled when the goods are sold.

Unsolicited calls and text messages: telemarketing calls and junk text messages can be minimised by preventing the sharing of telephone lists. Numbers using the service cannot be shared without also providing a valid PIN. The user 14 will know which PIN has been passed on and used because the call will be so announced. Therefore, the source from which the telemarketing company obtained the number can be traced.

Post-sales support: in some situations, retailers provide telephone support following the sale of an item. An example of this is the sale of computer equipment. At the point of sale, the retailer could provide the purchaser with their service number and a PIN, for telephone support. The PIN could be generated by their point of sale system and could have an IS automatic expiry date (for example, seven days from the date of sale or delivery or one year from that date). The customer could then call the service number (within the seven days or the year), give their name, and receive support for the item that they purchased.

The PIN could alternatively be given a certain useable time. Therefore, after the customer has used the customer service number to make more than perhaps an hour of telephone calls, the PIN could deactivate.

The present invention has been described above purely by way of example. It should be noted that modifications in detail may be made within the scope of the invention as defined in the claims.

Claims

1. A telephone security service comprising: a service number for a user or subscriber, retained by a service provider, the service number being the number that the user or subscriber can give to prospective callers for contacting the user or subscriber via the service, a target number for the user or subscriber for the service provider to call upon receiving a call on the service number from the prospective caller; a PIN for that caller, the PIN being required to be given to the service provider by the caller calling the service number before the caller's call can be connected or re-directed to the target number; and a tag for the caller to identify the caller, the tag being associated with the PIN by the service so that upon receipt of the PIN from the caller, the service can identify the caller, the tag not being the caller's caller ID; wherein, before re-directing a call from a caller to the target number, the service provides information concerning the tag for the PIN to the user or subscriber, or the target telephone of the user or subscriber, to give the user or subscriber, or the target telephone, the option to decide whether to take the call.

2. The service of claim 1, wherein the service number is different to the target number.

3. The service of claim 1, wherein the service number is the same as the target number and calls to the service number not accompanied by a PIN or having an invalid PIN are directed straightaway to a voicemail system.

4. The service of claim I, wherein the service number is the same as the target number and calls to the service number not accompanied by a PIN or having an invalid PIN are not connected to the target number.

5. The service of any one of the preceding claims, wherein the user or subscriber provides the tag for identifying the caller.

6. The service of any one of the preceding claims, wherein the tag is a voice tag.

7. The service of any one of the preceding claims, wherein the tag includes a word, data or image tag. s

8. The service of any one of the preceding claims, wherein the user or subscriber provides the PIN.

9. The service of any one of the preceding claims, wherein the service number is unique to the user or subscriber.

10. The service of any one of the preceding claims, wherein the user or subscriber has just one service number.

11. The service of any one of the preceding claims, wherein the target number can be selected or changed by the user or subscriber from or between any one of his own personal or business telephone or pager numbers.

12. The service of any one of the preceding claims, wherein service passes on caller ID information to the target telephone if the caller has not withheld his caller ID signal.

13. The service of any one of the preceding claims, wherein the service provider is a call centre administered by a communications network.

14. The service of any one claims I to 12, wherein the service provider is software implemented on a communications network

15. The service of any one claims 1 to 12, wherein the service provider is a program retained in a telephone handset or in a company's telephone network.

16. The service of any one of the preceding claims, wherein the user or subscriber can interact with the service provider to set up new PlNs for new callers so that the service provider can identify the new callers from the new PlNs.

17. The service of claim 16, wherein the interaction is by vocal means.

18. The service of any one of the preceding claims, wherein the user or subscriber may perform the setting up of the service by keying in details on his telephone handset.

19. The service of any one of the preceding claims, wherein the user or subscriber may perform the setting up of the service via the internet.

20. The service of any one of the preceding claims, wherein multiple callers can be set up on the system, each with their own unique PIN and tag.

21. The service of any one of the preceding claims, wherein groups of callers can be set up, the callers in each group sharing the same PIN.

22. The service of any one of the preceding claims, wherein PINs can be cancelled or suspended to prevent the callers associated with those PINs from calling the user or subscriber either permanently or temporarily.

23. The service of any one of the preceding claims, wherein the service provider can upload PIN, caller and tag information (the service records) onto a database accessible via the internet or via an interactive handset, such as a WAP phone or handheld PC, for maintenance or administration of the service records by the user or subscriber on the internet or via the handset.

24. The service of any one of the preceding claims, wherein the service is adapted to recognise the PIN from a dialled number, where the PIN is attached to that dialled number at the end of the service number.

25. The service of claim 24, wherein the service number and PIN is stored in a caller's telephone phonebook and the PIN is separated from the service number by an appropriate command character, such as the "#" or pound sign.

26. The service of any one of the preceding claims, wherein the service is set up to filter calls selectively.

27. The service of claim 26, wherein the service filters calls at certain times. s

28. The service of claim 26 or 27, wherein the service filters calls by filtering certain callers from the service via the PINs used by callers.

29. The service of any one of the preceding claims, wherein the service can be set up to use a different target number at different or scheduled times of the day, week or year.

30. The service of any one of the preceding claims, wherein the service can be set up to transfer all or selected callers direct to voicemail at certain times of day, week or year.

31. The service of any one of the preceding claims, wherein the service checks incoming calls for caller IDs and filters out all calls that exclude a caller ID.

32. The service of any one of the preceding claims, wherein the service checks incoming calls for caller IDs and filters out all calls for certain PINs that exclude a caller ID.

33. The telephone security service substantially as hereinbefore described.

34. A telephone handset substantially as hereinbefore described.

35. A telephone communications network substantially as hereinbefore described.

36. A method of setting up a telephone security service according to any one of claims 1 to 33, comprising the steps of: providing for the service a service provider, a user or subscriber and an identification means for at least one caller; providing for the service a service number for accessing the service, providing for the service a target number for the user or subscriber, providing for the service a PIN for the at least one caller for enabling calls by the at least one caller to be re-directed to the user or subscriber by the service; and providing for the service a tag, associated with the PIN by the service, for providing to the user or subscriber before re-directing the call to the user or subscriber; wherein the service provider maintains the PIN and associated tag in a database accessible to the user or subscriber for administration purposes.

37. A method of operating a telephone security service as defined in any one of claims I to 33, comprising the steps of: receiving a call from a caller who has dialled a service number and who has additionally provided a PIN; determining whether the PIN is a valid PIN for the service number dialled, and, if it is, determining the tag for the PIN and providing information concerning the tag to the user or subscriber assigned the service number or to the target telephone of the user or subscriber assigned the service number to give the user or subscriber, or the target telephone, the option to decide whether to take the call.

38. A method of setting up and/or administering a telephone security service substantially as hereinbefore described.