GB2324675A

GB2324675A - Telephone call screening

Info

Publication number: GB2324675A
Application number: GB9708013A
Authority: GB
Inventors: Roger John Pittock
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-04-21
Filing date: 1997-04-21
Publication date: 1998-10-28
Also published as: GB9708013D0

Abstract

This invention describes a method and apparatus for automatically screening and segregating incoming telephone calls according to the identification of the telephone line originating the call and, optionally, the time of day or day of week, either for privacy, security or both. A straightforward means of updating authorised and banned caller identification is included. Galvanic isolation is maintained between the telephone line of the service provider and the screened telephonic equipment unless the call is identified as an allowed call, although the galvanic isolation may optionally be automatically bypassed if screened equipment or an attender thereof attempts to initiate a call. This approach renders unauthorised callers unaware of any automatic answering equipment that may be connected on the screened side of the apparatus and alleviates occupants of properties deploying this invention from telephonic equipment ringing when call answering is not to occur, without untoward side effects.

Description

Telephone Call Screening This invention relates to an apparatus that connects between the telephone line of a telephone service provider and telephonic equipment ordinarily connected directly to the telephone line of the service provider, to segregate wanted from unwanted incoming calls according to the caller identification signal. It is referred elsewhere in this paper as Selective Caller Access (SCA). The call segregation can be for purposes of security, privacy or both. Additionally, certain telephonic equipment and facilities may be incorporated within the apparatus, minimising the number of pieces of equipment for a given installation. Both the security and privacy purposes afford similar methods. However detail differences and emphasis of facilities differ as described and apparatus may be constructed taking some facilities from each approach.

Some telephone service providers offer a service whereby, unless preemptively suppressed, the telephone number of the originators of incoming calls is where possible made available to the recipient. Subscribers to the caller identification facility may identify the originating number of an incoming call or be advised the fact that none is available or that the number has been withheld by the caller. Notification is typically by observation of a display, although certain computer-based systems such as that used by Sk8roadcasting Systems log the information and compare with/update a preexisting database to perform and schedule alternative functions. Based on the displayed information and the time of day/day of week, the recipient may elect to answer the call or allow the call to go unanswered. For example, if the telephone number of the caller was recognised as that of a friend, neighbour or family member, it is likely that one would wish to answer the call whatever the time of day or night. Conversely, if the telephone number of the caller was recognised as that of a persistent salesman or withheld deliberately, one may elect not to answer the call whatever the time of day. It is probable that unrecognised callers' numbers will be typically attended depending on the time of day and day of the week. Telephone line users who do not subscribe to the caller identification system or who do not have a display available have restricted information available on which to base their decision whether to answer the telephone.

If telephone users receive occasional wrong numbers at inconventient times (eg when house occupants are sleeping), telephone equipment may be preemptively unpiugged from the service provider's line for the period when rest is required. Alternatively, telephonic equipment offering the facility may have the call alert/bell system preemptively suppressed for the period of rest. However, both approaches have the disadvantage that a close friend, neighbour or family member who may wish to alert of an urgent situation would be unable to do so immediately by telephone. Also, the isolation method of call suppression requires equipment to be reconnected to allow a call to be initiated. Further, either of the methods of call suppression described above requires discipline to remember to suppress on retiring and to enable calls on arising.

Telephone access to certain items of automated equipment allows data exchange and remote control of domestic/industrial equipment by telephone contact. Examples include answerphones with remote message access, alarm systems with remote enable/disable and computer systems linked to the telephone system via a modem. In many cases all of the locally offered facilities can be activated using the telephone. Nefarious access ("hacking") is possible once the intruder is aware of the existence of remotely controllable equipment or remotely accessible computer systems. Although such systems can be, and are often, password/PIN protected, professional hackers invariably crack such systems

Telephone Call Screening using highly sophisticated software and hardware. For this reason, network access of data from site to site of MOD-approved companies has hitherto not been permitted using standard telephone lines as such access breaches network firewall security.

According to the present invention, a method and apparatus provides isolation between the service provider's telephone line and telephonic equipment connected to the screened output of the apparatus for incoming calls, but not for outgoing calls, where isolation is dependent on comparison of the caller identification signal of the incoming call and previously stored telephone numbers in lists on the apparatus, optionally with a further comparison to the time of day or day of week.

Two specific embodiments of the invention are described in detail by way of example with reference to the accompanying drawings. The first embodiment is predominantly for domestic privacy from unwanted calls and the second embodiment is predominantly for data security.

Figure 1 shows the basic apparatus for domestic privacy in block diagram form connected between telephonic equipment and the service provider's telephone line.

Figure 2 shows a variation for domestic/industrial security in block diagram form connected between telephonic equipment and the service provider's telephone line.

Figure 3 shows additional elements of the system required to accommodate other embodiments referred in text.

Both embodiments of the invention described in full detail make use of the BTcaller identification system and refer to telephone plugs and sockets. However, the system is applicable mutatis mutandis for any telephone service provider where caller identification is available to recipients prior to answering of incoming calls, with any appropriate connector system or where some or all connections are hard wired. For callers from certain exchanges and certain mobile phones, unless preemptively suppressed, the telephone number of the call originators is typically available to recipients subscribing to the caller identity transmissions. The number of the current caller is made available preemptively by electronic transmission down the telephone line immediately prior to transmission of the bell signal. For purposes of example, Number Withheld" and "Number Unavailable" and similar messages are treated as if unique numbers. Prior art allows the caller's telephone number and other detail to be displayed on an electronic alphanumeric display or provided to computer systems for interactive database use. The display can be either on the telephone instrument or on a piece of auxiliary equipment connected to the line.

In the first elucidated embodiment of this invention: Please refer to Figure 1 with the explanations below of the basic domestic (privacy biassed) SCA unit. The SCA and co ponents are in block (1). The BT-style plug (2) is typically connected to the Brine socket (3). The signal (4) is fed to the multipole relay (5), whose normally closed output signal (6) is fed to the screened telephone socket (STS) (7). Telephonic equipment to be screened (8), such as a remotely accessible burglar alarm or the domestic telephone may be plugged into

Telephone Call Screening the STS. The signal (4) also feeds Caller Identification Extraction Circuitry (CIEC) (9). A digital signal feeds caller identification information of any incoming call that may be arriving to the Central Processing Unit (CPU) (10). The signal (4) also feeds linein-use detect (LIUD) circuitry (11). This feeds a signal (12) to the CPU advising of the line status (free, call coming in, line clearing etc.). A manual input device (MID) (13) interfaces with the CPU. This allows entry/modification of stored caller/time/day information. Off-hook detect (OHD) circuit (14) containing a galvanic isolation barrier (15) samples the impedance of equipment connected to the STS.

Optionally, an additional normally connected telephone socket (NCTS) (16) may be connected to the normally open contacts of the multipole relay. Telephonic equipment not requiring such screening, such as an answerphone system without remote access to stored messages (17) may be plugged into this socket. A further option is the inclusion of an electronic mesesage/tone generator (EMTG) (18) with isolation barrier (15) to provide tonalivocal feedback to screened equipment or users thereof if, when the receiver is lifted, the service provider's line is not to be immediately connected. By default on power up, the relay is energised and remains so except in certain conditions as described below.

When an incoming call is detected, before the ringing tone, the CIEC establishes the callers number and sends that detail along with the date and time of the call to the CPU. If the caller identification so transmitted matches that on the list of preferred callers stored in the CPU, the CPU unenergises the multipole relay, allowing any telephonic equipment plugged into the STS access to the service provider's line.

When the line is cleared by the caller hanging up, the LIUD circuit informs the CPU which in turn energises the multipole relay. If an NCTS is also provided, it is de facto disabled during the call.

If the calling number of the detected incoming call is on the banned list as stored in the SCA unit, the relay remains energised; equipment plugged into the STS remains galvanically isolated from the service provider's line. If an NCTS is also provided, any equipment (17) connected to that socket will ring and may answer the incoming call.

If the calling number of the detected incoming call is on neither stored list, the time of day/day of week of the incoming call is compared to the allowable range for nonstored callers. If the time/day is amenable and the call is to be allowed, the call is treated as if the caller identification was on the preferred list. If the call falls in an unacceptable time band, the call is treated as if the caller identification were on the banned list.

Local means is provided to allow creation/modification of the preferred list, the banned list and the permitted time bands for unlisted callers. In the described embodiment, this is achieved with keys and an alphanumeric display, although an option may be to utilise a standard telephone keypad plugged into the unit and voice feedback from electronic message store. A novel means to add a number to either the preferred list or the banned list would be to include a button for each list, perhaps labelled 'preferred last caller' and "banned last caller" respectively. In that way, if an incoming call was received (either via the SCA or direct, but with the SCA Telephone Call Screening equipment connected to the telephone line), the caller could be identified by voice and the number added to the list of choice, without any possibility of keying in a wrong number. A further simple means to allow review of lists with the option to delete selective entries on either list would be the preferred option for domestic SCA units. An alternative would be to include a facility to allow a standard telephone dial/keypad mechanism plugged into the unit (either via sockets previously advised or via a separate socket) in conjunction with either a display on the unit or electronically generated vocal feedback/instruction.

A further facility of this invention allows the screened telephonic equipment to preemptively take control of the service provider's line to initiate an outgoing telephone call. This may happen for example when an occupant picks up the handset on screened telephonic equipment to make a telephone call. It may similarly happen in a security system that alerts the local constabulary by telephone in the event of a detected break-in. When screened equipment connected to STS (7) attempts to initiate a call (or someone picks up a handset within such equipment), the OHD circuit detects this event and informs the CCU. Provided the LIUD confirms the service provider's line is free, the CPU unenergises the multipole relay, connecting the screened telephonic equipment to the service provider's line, allowing the call to be placed. When the line is cleared by the caller hanging up, the LIUD circuit informs the CPU which energises the multipole relay, reinstating the call privacy. If an NCTS is also provided, it is de facto disabled during this call. If, when said screened equipment attempts to initiate the call, the service provider's line were not free, for example an incoming call that was banned is ringing in or a call is in progress initiated or received outside of the SCA, the LIUD will have already advised of this situation to the CPU and the relay will not immediately be unenergised. If the unattended incoming call is terminated by the caller hanging up before the screened telephonic equipment gives up, the CPU unenergises the relay allowing the screened equipment to initiate a call as above. An optional electronic vocal, tonal or data message advising of the busy line can be transmitted to the screened equipment in this unlikely event. If provided for, such a message would initiate from the EMTG under CPU control until the call attempt were abandoned or the service provider's line became free, whichever were the sooner.

With the normally closed relay scenario described, a power failure to the SCA allows all calls through on the STS, ensuring that calls can be received or made in an emergency or abnormal situation.

In the second elucidated embodiment of this invention: Please refer to Figure 2 with the explanations below of the basic industrial (security biassed) SCA unit. The SCA and components are in block (1). The BT-style plug (2) is typically connected to the BTline socket (3). The signal (4) is fed to the multipole relay (5), whose normally open output signal (6) is fed to the screened telephone socket (STS) (7). Telephonic equipment to be screened (8), such as a computer-based modem, may be plugged into the STS. The signal (4) also feeds Caller Identification Extraction Circuitry (CIEC) (9). A digital signal feeds caller identification information of any incoming call that may be arriving to the Central

Telephone Call Screening Processing Unit (CPU) (10). The signal (4) also feeds line-in-use detect (LIUD) circuitry (11). This feeds a signal (12) to the CPU advising of the line status (free, call coming in, line clearing etc.). A connection for an interface (13) is connected via appropriate interface circuitry within the CPU. Connection of compatible equipment here allows entry/modification of stored caller information and other parameters, such as whether outgoing calls are permitted, whether a specific number of calls from a given user only are permitted etc. Off-hook detect (OHD) circuit (14) containing a galvanic isolation barrier (15) samples the impedance of equipment connected to the STS. A further option is the inclusion of an electronic mesesage/tone generator (EMTG) (18) with isolation barrier to provide tonal/vocal feedback to screened equipment or users thereof if, when the receiver is lifted, the service provider's line is not to be connected. By default on power up, the relay is unenergised and remains so except in certain conditions as described below.

When an incoming call is detected, the CIEC detects the caller's number and sends that detail along with the date and time of the call to the CPU. If the caller identification and allowed date/time combination so transmitted matches that on the preferred list of caller details stored in the CPU, the CPU energises the multipole relay, connecting any plugged-in telephonic equipment to the STS. When the line is cleared by the caller hanging up, the LIUD circuit informs the CPU, which in turn unenergises the multipole relay. For all other situations of incoming call, said telephonic equipment remains isolated from the service provider's line.

A means is provided to allow creation/modification of the access list. Optionally this can be done offline on a computer terminal and downloaded over, eg, a serial link.

Optionally also access to the list for modification/addition may be protected by a keyswitch or electronic means (such as a PIN).

A further facility of this invention optionally allows the screened telephonic equipment to preemptively take control of the service provider's line to initiate an outgoing telephone call or to remain isolated under such an attempt at call initiation.

In the case of automatic connection: This may happen for example for scheduled transfer of data by fax or modem. It could similarly happen if any equipment so connected has a handset to allow outgoing calls and for scheduled transfer of data by fax or modem. When the screened equipment connected to the STS (7) attempts to initiate a call (or someone picks up a handset within such equipment), the OHD circuit detects this event and informs the CCU. Provided the LIUD confirms the service provider's line is free, the CPU energises the multipole relay, connecting said screened equipment to the service provider's line allowing the call to be placed. When the line is cleared by the screened equipment or caller hanging up, the LIUD circuit informs the CPU which unenergises the multipole relay maintaining the remote access security. If, when said screened equipment attempts to initiate the call, the service provider's line is not free, for example an incoming call is ringing in whose identity and time stamp does not match one on the authorised list, the LIUD will have already advised of this situation to the CPU and the relay will not be energised. If the unattended incoming call is Telephone Call Screening terminated by the caller hanging up before the screened telephonic equipment gives up, the CPU subsequently closes the relay allowing the screened equipment to initiate a call as above. An optional electronic vocal, tonal or data message advising of the busy line can be transmitted to the screened equipment if such a clash arises. If provided for, such a message would initiate from the EMTG (18) under control of the CPU.

In the case of retained isolation: This facility is mutually exclusive at any given time to the facility of automatic connection described above. If screened equipment attempts to initiate a call, galvanic isolation may be maintained in the event of telephonic equipment or users thereof attempting to initiate outgoing communication. An optional electronic vocal, tonal or data message advising of the non-availability can be transmitted to the screened equipment. If provided for, such a message would initiate from the EMTG (18) under control of the CPU.

The availability of one or other of the facilities of automatic connection or retained isolation for outgoing call attempts may be hard encoded in the SCA equipment or programmable as part of the user-defined parameter list.

Because the relay is normally open, isolation and security are maintained in the event of system power failure or battery exhaustion.

Main uses and additional embodiments of the invention: Nocturnal call screening: This invention provides for a means to prevent the bell of a domestic telephone ringing at prescribed times unless the caller is a close friend or a family member. For this use, an NCTS need not be included. The time parameters may optionally be different on weekdays from Saturday, which may optionally be different also from the Sunday access period. A real time clock is not required if the caller identification codes contain current date and time information.

However, such a clock could be included as an additional facility, where the caller identification information automatically affirms/resets the clock to the date/time sent via the subscriber as part of the call identification signal.

Integral telephone handset: Although the elucidated embodiments above refer to screened equipment plugged in to the STS (7), alternative embodiments may include an integral telephone (21) connected to the screened output within the apparatus, either instead of or in addition to the STS. Given this facility, a keypad decoder and galvanic isolation system (22) may be included to allow modification of the lists, in conjunction with either electronic voice prompts or an alphanumenric display on the unit or handset.

Answerphonelfax compatibilitylenhancement: Equipment connected to the STS is adjusted to answer calls after a certain number of rings. Any preexisting or separate answerphone or fax connected direct to the telephone line (3) (without going through the SCA) is adjusted to answer after a greater number of rings than the equipment connected via the SCA. In this way, callers not recognised by the Telephone Call Screening SCA are still attended without breach of the security system described.

Alternatively, preexisting answerphone or fax equipment may be connected to the NCTS instead of direct to a service provider's line socket, making the number of rings before answering non critical. Should a caller from an authorised telephone wish to connect to the preexisting answerphone or fax, this is achieved by preemptively withholding the caller's identity (eg, by preceding the called number with 141 for BT-supplied services). A useful benefit is that attempted use of telephonic equipment connected to the NCTS will not inadvertently corrupt data transmission on the STS and vice versa as connection to the service provider's line is mutually exclusive and prioritised by the call in progress.

Inbuilt answerphone/fax: Alternatively to the above, an answerphone, fax or combination of both may optionally be included as an integral part of the equipment described in this paper on Uup-market" models. Such equipment would be connected as if to an NCTS internally and the same useful benefit would apply.

Inbuilt intelligent answerphone: A further development of the above could consist of an inbuilt answerphone system in the apparatus offering a plurality of outgoing messages, to be automatically selected depending on caller identity. Default electronic options could be included for each selection, with the option to manually override with one's own outgoing message. For example, Number Withheld" callers could receive one message, blacklisted callers another, unlisted callers yet another and, in the event of a preferred call arriving but not being attended (eg due to occupant absence or lack of auto-answer equipment response), a further outgoing message could be used. The option of allowing a retum message to be left for each outgoing message group can be selectable in much the same way as one can globally select that option on a standard existing answerphone system. Similarly, access to messages left from a remote system (via a PIN) is similarly available, but this may optionally be restricted preemptively to either the preferred list or by a further dedicated caller identity list containing, eg, the house occupant's own mobile and works office number only.

Call segregation: If the NCTS is routed to the main telephone and an alternative phone to the STS, an automatic call splitter is created. Incoming calls not on the list are routed to the NCTS, with the STS remaining isolated. Incoming calls on the list are routed to the STS, with the NCTS temporarily isolated. An additional benefit of this system is that telephonic equipment connected to either socket can initiate or receive a call, with no possibility that equipment connected to the other socket can inadvertently interrupt or disturb that call. This facility may be useful for guest houses or granny annexe scenarios where the expense of a second line maybe saved. With the inclusion of two more simple circuits in the SCA, call transfer from the normally connected socket to the protected socket is possible by pressing a single button on the SCA. The transfer push-button, included as part of the interface unit (13) would interface with the CPU. The additional blocks, shown in Figure 3, would be a line-hold circuit (19) energised for the duration of the transfer by the CPU and a galvanically isolated bell signal generator (20), also CPU-driven. During the transfer operation, the line-hold circuit would retain the call while the bell circuit would cause equipment connected to the protected socket to ring. As soon as the Telephone Call Screening LIUD detects that the receiver has been lifted on the equipment connected to the protected socket, the bell signal generator is disabled, the relay is closed and the line-hold circuit disabled in that order. Optionally the line-hold circuit may generate an artificial Uburr-burr" for the caller pending transfer. If the transfer call is not answered after a predetermined period of time, the line-hold circuit drops out and the bell is disabled. For completion, if the call fails, the line hold circuitry may be instructed to provide a number unobtainable tone for a few seconds before dropping out completely.

Multiple separate secure outlets: By replication of the relay, STS and OHD, optionally replicating or switch routing the optional electronic vocal message/tone generator, with a minor increase in complexity of the CPU to hold more preferred lists and to control the replicated circuits, incoming calls can be automatically unanswered, internally answered by answerphonelfax or routed to one or many of several STSs for extemal receiving equipment, depending on the caller identification signal of the call originator. This situation may be useful for families with teenage children! Numbers may appear on more than one list. If this happens, relays for all channels recognising the number of an incoming caller will close for the duration of the call. Any protected outlet initiating a call automatically gains privacy from other protected outlets during a call.

Claims

Telephone Call Screening

Claims A A method that provides isolation between the service provider's telephone line and telephonic equipment for incoming calls, but not for outgoing calls, where isolation is dependent on comparison of the caller identification signal of the incoming call and previously stored telephone numbers in lists on the apparatus, optionally with a further comparison to the time of day or day of week.
2 The method of claim 1 where the isolation allows wildcard entries in one or both of the preferred list and the banned list (eg to allow or disallow access from certain area codes only).
3 The method of claim 1 or claim 2 where individually identified calling sources optionally have date/time bands associated with them further restricting access.
4 The method of claim 1 or claim 2 where the isolation is time-of-day dependent to allow only specific (preferred) telephone calls through during certain hoursidays but to allow all calls not on the banned list through outside those selected time/day bands.
5 The method of any previous claim where the system has an alphanumeric display and simple switches/pushbuttons to allow list entries to be reviewed and/or removed.
6 The method of any previous claim where the system also contains an answerphone, fax receiver, both or a combined answerphone/fax system. Identified callers on the preferred list are routed to the otherwise isolated socket on the equipment, while other callers are routed to the inbuilt answerphone and/or fax system. Should an identified caller require access to the additional facility instead of the isolated socket, the caller can, for that purpose, preemptively withhold the originating number.
7 The method of any previous claim where the system contains an answerphgone offering a plurality of outgoing messages, selected depending on whether the incoming caller identification is on the local preferred list, the local banned list or neither list.
8 The method of claim 7 where a further unique outgoing message may be selected for "Number withheld" calls.
9 The method of claim 7 or claim 8 where remote access of messages left on the answerphone or alternative answerphone facilities may be restricted to callers from either the local approved list or alternatively an additional list of caller identifications dedicated to that purpose, said list being manipulated substantially as other lists.
10 The method of any previous claim where a simple operation (such as a single keystroke on the unit) allows the last incoming caller identification signal to be added to either the local preferred list or the local banned list.
11 The method of any previous claim where the local list(s) may be uploaded to, created or modified on and downloaded from a local computer-based system.

Telephone Call Screening 12 The method of any previous claim where the local lists may be reviewed or modified by use of a standard telephone instrument in conjunction with either a display on the SCA, electronically generated vocal/tone messages or both.

13 The method of any previous claim where the system contains an inbuilt handset and dial/keypad mechanism as if connected to the screened output, to allow making of calls and screening of received calls without additional telephonic equipment. This telephone handset/keypad may be in place of or in addition to the secure socket.

14 The method of claim 13 where the built-in handset may be used to portray electronicly generated audio representations of the numbers in the lists.

15 The method of claim 13 where the built-in dial pad may be used to add a number to one or other of the stored lists.

16 The method of any previous claim where modification of the lists is itself security protected by electronic means, keyswitch, removal of the entry device from the apparatus or any combination thereof.

17 The method of any previous claim where a connection is automatically made in the event of any telephonic equipment plugged into the unit attempting to connect provided that the main line is free.

18 The method of any previous claim except claim 17 where galvanic isolation is maintained if screened telephonic equipment attempts to initiate an outgoing call.

19 The method of claim 18 where an electronically generated vocal method, data or tone advises that the facility is not available.

20 The method of claim 17, claim 18 and claim 19 where selection between facilities is a user programmable option in accordance with the methods described in any of claim 11 to claim 16 inclusive.

21 The method of any previous claim except claim 18 where a connection is not made in the event of any telephonic equipment plugged into the unit attempting to connect when the main line is not free.

22 The method of claim 21 where an electronically generated vocal method, data or tone advises that the line is not free.

23 The method of any previous claim where an outlet is also provided out of phase with the secure outlet (ie a socket that is connected to the service provider's line except when secure access is permitted). Incoming calls are routed to one or other outlet dependent on caller identification. Outgoing calls can be initiated from either socket.

24 The method of claim 23 where facility is included to transfer a call to the secure outlet.

Telephone Call Screening 25 The method of claim 23 where data transfer or speech on the one socket is protected from inadvertent interruption, corruption or eavesdropping by accidental or nefarious attempted use of equipment connected on another socket.

26 The method of any previous claim where a plurality of secure sockets exist, each with individual lists and selective incoming call capability and each of which may initiate an outgoing call, excluding all others for the call duration.

27 The method of any previous claim where a power failure or battery exhaustion of the system provides telephone continuity for domestic convenience or automatic alert of potential intrusion by burglar alarm systems and the like.

28 The method of any previous claim except claim 27 where a power failure or battery exhaustion of the system maintains isolation for continued data security.

29 The method of any previous claim where a real time clock facility is included that is automatically set on the first received call after power-up and is adjusted periodically on receipt of telephone calls in accordance with the time/date stamp provided as part of the caller identity information.

30 An apparatus that provides isolation between the service provider's telephone line and telephonic equipment for incoming calls, but not for outgoing calls, where isolation is dependent on comparison of the caller identification signal of the incoming call and previously stored telephone numbers in lists on the apparatus, optionally with a further comparison to the time of day or day of week.

31 The apparatus of claim 30 where the isolation allows wildcard entries in one or both of the preferred list and the banned list (eg to allow or disallow access from certain area codes only).

32 The apparatus of claim 30 or 31 where individually identified calling sources optionally have date/time bands associated with them further restricting access.

33 The apparatus of claim 30 or 31 where the isolation is time-of-day dependent to allow only specific (preferred) telephone calls through during certain hours/days but to allow all calls not on the banned list through outside those selected time/day bands.

34 The apparatus of any previous claim where the equipment has an alphanumeric display to allow list entries to be reviewed and/or removed.

35 The apparatus of any previous claim where the system also contains an answerphone, fax receiver, both or a combined answerphone/fax system. Identified callers on the preferred list are routed to the otherwise isolated socket on the equipment while other callers are routed to the inbuilt answerphone and/or fax system. Should an identified caller require access to the additional facility instead of the isolated socket, the caller can, for that purpose, preemptively withhold the originating number.

Telephone Call Screening 36 The apparatus of any previous claim where the equipment contains an answerphone offering a plurality of outgoing messages, selected depending on whether the incoming caller identification is on the local preferred list, the local banned list or neither list.

37 The apparatus of claim 36 where a further unique outgoing message may be selected for Number withheld" calls.

38 The apparatus of claim 36 or claim 37 where remote access of messages left on the answerphone or alternative answerphone facilities may be restricted to callers from either the local approved list or alternatively an additional list of caller identifications dedicated to that purpose, said list being manipulated substantially as other lists.

39 The apparatus of any previous claim where a simple operation (such as a single keystroke on the unit) allows the last incoming caller to be added to either the local preferred list or the local banned list.

40 The apparatus of any previous claim where the local list may be uploaded to, created or modified on and downloaded from a local computer-based system.

41 The apparatus of any previous claim where the local lists may be reviewed or modified by use of a standard telephone keypad or dial on telephonic equipment plugged into one or other described socket or a dedicated socket on the SCA, in conjunction with either a display on the SCA, electronically generated vocal/ tone messages or both.

42 The apparatus of any previous claim where the equipment contains an inbuilt handset and diailkeypad mechanism as if connected to the screened output, to allow making of calls and screening of received calls without additional telephonic equipment. This telephone handset/keypad may be in place of or in addition to the secure socket.

43 The apparatus of claim 42 where the built-in handset may be used to portray electronically generated audio representations of the numbers in the lists.

44 The apparatus of claim 42 where the built-in dial pad may be used to add a number to one or other of the stored lists.

45 The apparatus of any previous claim where modification of the list is itself security protected by electronic means, keyswitch, removal of the entry device from the apparatus or any combination thereof.

46 The apparatus of any previous claim where a connection is automatically made in the event of any telephonic equipment plugged into the unit attempting to connect provided that the main line is free.

47 The apparatus of any previous claim except claim 46 where galvanic isolation is maintained if screened telephonic equipment attempts to initiate an outgoing call.

Telephone Call Screening 48 The apparatus of claim 47 where an electronically generated vocal signal or data signal advises that the facility is not available.

49 The apparatus of claim 46, claim 47 and claim 48 where selection between facilities is a user programmable option in accordance with facilities provided by the apparatus described in any combination of claims 40 to claim 45 inclusive.

50 The apparatus of any previous claim where a connection is not made in the event of any telephonic equipment plugged into the unit attempting to connect when the main line is not free.

51 The apparatus of claim 50 where an electronically generated vocal method or data advises that the line is not free.

52 The apparatus of any previous claim where an outlet is also provided out of phase with the secure outlet (ie a socket that is connected to the service provider's line except when secure access is permitted). Incoming calls are routed to one or other outlet dependent on caller identification. Outgoing calls can be initiated from either socket.

53 The apparatus of claim 52 where facility is included to transfer a call to the protected side.

54 The apparatus of claim 52 where data transfer or speech on the one socket is protected from inadvertent interruption, corruption or eavesdropping by accidental or nefarious attempted use of equipment connected on another socket.

55 The apparatus of any previous claim where a plurality of secure sockets exist, each with individual lists and selective incoming call capability and each of which may initiate an outgoing call, excluding all others for the call duration.

56 The apparatus of any previous claim which draws its primary power source from any combination of disposable batteries, transformed mains, rechargeable battery or the system provider's telephone line.

57 The apparatus of any previous claim where the primary power source is backed up during power failures by either rechargeable or disposable batteries.

58 The apparatus of claim 57 using rechargeable batteries that provides a means to recharge/maintain their charge.

59 The apparatus of any previous claim where a power failure or battery exhaustion of the system provides telephone continuity for domestic convenience or automatic alert of potential intrusion by burglar alarm systems and the like.

60 The apparatus of any previous claim except claim 59 where a power failure or battery exhaustion of the system maintains isolation for continued data security.

61 The apparatus of any previous claim where a real time clock is included and the time Telephone Call Screening and/or date is displayed on the unit. The time/date is automatically set on the first received call after power-up and is adjusted periodically on receipt of telephone calls in accordance with the time/date stamp provided as part of the caller identity information.

62 The apparatus or method of any previous claim where certain connections may be hard-wired instead of connected via plugs/sockets for additional security.

Amendments to the claims have been filed as follows 1 ,, A method that provides isolation between the service provider's telephone line and telephonic equipment for incoming calls, but not for outgoing calls, where isolation is dependent on comparison of the caller identification signal of the incoming call and previously stored telephone numbers in lists on the apparatus, optionally with a further comparison to the time of day or day of week.

2 The method of claim 1 where the isolation allows wildcard entries in one or both of the preferred list and the banned list (eg to allow or disallow access from certain area codes only).

3 The method of claim 1 or claim 2 where individually identified calling sources optionally have date/time bands associated with them further restricting access.

4 The method of claim 1 or claim 2 where the isolation is time-of-day dependent to allow only specific (preferred) telephone calls through during certain hours/days but to allow all calls not on the banned list through outside those selected time/day bands.

5 The method of any previous claim where the system has an alphanumeric display and simple switcheslpushbuttons to allow list entries to be reviewed and/or removed.

6 The method of any previous claim where the system also contains an answerphone, fax receiver, both or a combined answerphonelfax system. Identified callers on the preferred list are routed to the otherwise isolated socket on the equipment, while other callers are routed to the inbuilt answerphone and/or fax system. Should an identified caller require access to the additional facility instead of the isolated socket, the caller can, for that purpose, preemptively withhold the originating number.

7 The method of any previous claim where the system contains an answerphgone offering a plurality of outgoing messages, selected depending on whether the incoming caller identification is on the local preferred list, the local banned list or neither list.

8 The method of claim 7 where a further unique outgoing message may be selected for "Number withheld" calls.

9 The method of claim 7 or claim 8 where remote access of messages left on the answerphone or alternative answerphone facilities may be restricted to callers from either the local approved list or alternatively an additional list of caller identifications dedicated to that purpose, said list being manipulated substantially as other lists.

10 The method of claim 7, claim 8 or claim 9 where a key sequence pressed by the caller under instruction of the answerphone's message precipitates an alert tone to encourage the occupant to attend the call personally.

il The method of any previous claim where a simple operation (such as a single keystroke on the unit) allows the last incoming caller identification signal to be added to either the local preferred list or the local banned list.
12 The method of any previous claim where the local list(s) may be uploaded to, created or modified on and downloaded from a local computer-based system.
13 The method of any previous claim where the local lists may be reviewed or modified by use of a standard telephone instrument in conjunction with either a display on the SCA, electronically generated vocal/tone messages or both.
14 The method of any previous claim where the system contains an inbuilt handset and dial/keypad mechanism as if connected to the screened output, to allow making of calls and screening of received calls without additional telephonic equipment. This telephone handset/keypad may be in place of or in addition to the secure socket.
15 The method of claim 14 where the built-in handset may be used to portray electronicly generated audio representations of the numbers in the lists.
16 The method of claim 14 where the built-in dial pad may be used to add a number to one or other of the stored lists.
17 The method of any previous claim where modification of the lists is itself security protected by electronic means, keyswitch, removal of the entry device from the apparatus or any combination thereof.
18 The method of any previous claim where a connection is automatically made in the event of any telephonic equipment plugged into the unit attempting to connect provided that the main line is free.
19 The method of any previous claim except claim 18 where galvanic isolation is maintained if screened telephonic equipment attempts to initiate an outgoing call.
20 The method of claim 19 where an electronically generated vocal method, data or tone advises that the facility is not available.
21 The method of claim 18 claim 19 and claim 20 where selection between facilities is a user programmable option in ccordance with the methods described in any of claim 12 to claim 17 inclusive.
22 The method of any previous claim except claim 19 where a connection is not made in the event of any telephonic equipment plugged into the unit attempting to connect when the main line is not free.
23 The method of claim 22 where an electronically generated vocal method, data or tone advises that the line is not free.
24 The method of any previous claim where an outlet is also provided out of phase with the secure outlet (ie a socket that is connected to the service provider's line except when secure access is permitted). Incoming calls are routed to one or other outlet dependent on caller identification. Outgoing calls can be initiated from either socket.
25 The method of claim 24 where facility is included to transfer a call to the secure outlet.
26 The method of claim 24 where data transfer or speech on the one socket is protected from inadvertent interruption, corruption or eavesdropping by accidental or nefarious attempted use of equipment connected on another socket.
27 The method of any previous claim where a plurality of secure sockets exist, each with individual lists and selective incoming call capability and each of which may initiate an outgoing call, excluding all others for the call duration.
28 The method of any previous claim where a power failure or battery exhaustion of the system provides telephone continuity for domestic convenience or automatic alert of potential intrusion by burglar alarm systems and the like.
29 The method of any previous claim except claim 28 where a power failure or battery exhaustion of the system maintains isolation for continued data security.
30 The method of any previous claim where a real time clock facility is included that is automatically set on the first received call after power-up and is adjusted periodically on receipt of telephone calls in accordance with the time/date stamp provided as part of the caller identity information.
31 An apparatus that provides isolation between the service provider's telephone line and telephonic equipment for incoming calls, but not for outgoing calls, where isolation is dependent on comparison of the caller identification signal of the incoming call and previously stored telephone numbers in lists on the apparatus, optionally with a further comparison to the time of day or day of week.
32 The apparatus of claim 31 where the isolation allows wildcard entries in one or both of the preferred list and the banned list (eg to allow or disallow access from certain area codes only).
33 The apparatus of claim 31 or 32 where individually identified calling sources optionally have date/time bands associated with them further restricting access.
34 The apparatus of claim 31 or 32 where the isolation is time-of-day dependent to allow only specific (preferred) telephone calls through during certain hours/days but to allow all calls not on the banned list through outside those selected time/day bands.
35 The apparatus of any previous claim where the equipment has an alphanumeric display to allow list entries to be reviewed and/or removed.
36 The apparatus of any previous claim where the system also contains an answerphone, fax receiver, both or a combined answerphone/fax system. Identified callers on the preferred list are routed to the otherwise isolated socket on the equipment while other callers are routed to the inbuilt answerphone and/or fax system. Should an identified caller require access to the additional facility instead of the isolated socket, the caller can, for that purpose, preemptively withhold the originating number.
37 The apparatus of any previous claim where the equipment contains an answerphone offering a plurality of outgoing messages, selected depending on whether the incoming caller identification is on the local preferred list, the local banned list or neither list.
38 The apparatus of claim 37 where a further unique outgoing message may be selected for "Number withheld" calls.
39 The apparatus of claim 37 or claim 38 where remote access of messages left on the answerphone or alternative answerphone facilities may be restricted to callers from either the local approved list or alternatively an additional list of caller identifications dedicated to that purpose, said list being manipulated substantially as other lists.
40 The apparatus of claim 37 , claim 38 or claim 39 where a key sequence pressed by the caller under instruction of the answerphone's message may precipitate an alert tone to encourage the occupant to attend the call personally. Said alert tone may be produced in a dedicated sounder in the SCA equipment or the bell of a connected telephone may be deployed.
41 The apparatus of any previous claim where a simple operation (such as a single keystroke on the unit) allows the last incoming caller to be added to either the local preferred list or the local banned list.
42 The apparatus of any previous claim where the local list may be uploaded to, created or modified on and downloaded from a local computer-based system.
43 The apparatus of any previous claim where the local lists may be reviewed or modified by use of a standard telephone keypad or dial on telephonic equipment plugged into one or other described socket or a dedicated socket on the SCA, in conjunction with either a display on the SCA, electronically generated vocal/ tone messages or both.
44 The apparatus of any previous claim where the equipment contains an inbuilt handset and dial/keypad mechanism as if connected to the screened output, to allow making of calls and screening of received calls without additional telephonic equipment. This telephone handset/keypad may be in place of or in addition to the secure socket.
45 The apparatus of claim 44 where the built-in handset may be used to portray electronically generated audio representations of the numbers in the lists.
46 The apparatus of claim 44 where the built-in dial pad may be used to add a number to one or other of the stored lists.
47 The apparatus of any previous claim where modification of the list is itself security protected by electronic means, keyswitch, removal of the entry device from the apparatus or any combination thereof.
48 The apparatus of any previous claim where a connection is automatically made in the event of any telephonic equipment plugged into the unit attempting to connect provided that the main line is free.
49 The apparatus of any previous claim except claim 48 where galvanic isolation is maintained if screened telephonic equipment attempts to initiate an outgoing call.
50 The apparatus of claim 49 where an electronically generated vocal signal or data signal advises that the facility is not available.
51 The apparatus of claim 48, claim 49 and claim 0 where selection between facilities is a user programmable option in accordance with facilities provided by the apparatus described in any combination of claims 42 to claim 47 inclusive.
52 The apparatus of any previous claim where a connection is not made in the event of any telephonic equipment plugged into the unit attempting to connect when the main line is not free.
53 The apparatus of claim 52 where an electronically generated vocal method or data advises that the line is not free.
54 The apparatus of any previous claim where an outlet is also provided out of phase with the secure outlet (ie a socket that is connected to the service provider's line except when secure access is permitted). Incoming calls are routed to one or other outlet dependent on caller identification. Outgoing calls can be initiated from either socket.
55 The apparatus of claim 54 where facility is included to transfer a call to the protected side.
56 The apparatus of claim 54 where data transfer or speech on the one socket is protected from inadvertent interruption, corruption or eavesdropping by accidental or nefarious attempted use of equipment connected on another socket.
57 The apparatus of any previous claim where a plurality of secure sockets exist, each with individual lists and selective incoming call capability and each of which may initiate an outgoing call, excluding all others for the call duration.
58 The apparatus of any previous claim which draws its primary power source from any combination of disposable batteries, transformed mains, rechargeable battery or the system provider's telephone line.
59 The apparatus of any previous claim where the primary power source is backed up during power failures by either rechargeable or disposable batteries.
60 The apparatus of claim 59 using rechargeable batteries that provides a means to recharge/maintain their charge.
61 The apparatus of any previous claim where a power failure or battery exhaustion of the system provides telephone continuity for domestic convenience or automatic alert of potential intrusion by burglar alarm systems and the like.
62 The apparatus of any previous claim except claim 61 where a power failure or battery exhaustion of the system maintains isolation for continued data security.
63 The apparatus of any previous claim where a real time clock is included and the time and/or date is displayed on the unit. The time/date is automatically set on the first received call after power-up and is adjusted periodically on receipt of telephone calls in accordance with the time/date stamp provided as part of the caller identity information.
64 The apparatus or method of any previous claim where certain connections may be hard-wired instead of connected via plugs/sockets for additional security.