WO1998047277A1 - Monitoring system and method - Google Patents

Monitoring system and method Download PDF

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Publication number
WO1998047277A1
WO1998047277A1 PCT/FI1998/000340 FI9800340W WO9847277A1 WO 1998047277 A1 WO1998047277 A1 WO 1998047277A1 FI 9800340 W FI9800340 W FI 9800340W WO 9847277 A1 WO9847277 A1 WO 9847277A1
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WO
WIPO (PCT)
Prior art keywords
connection
service node
communication channel
method according
service
Prior art date
Application number
PCT/FI1998/000340
Other languages
French (fr)
Inventor
Mika Hyvönen
Björn MELEN
Original Assignee
Telefonaktiebolaget Lm Ericsson (Publ)
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to FI971601 priority Critical
Priority to FI971601A priority patent/FI971601A0/en
Application filed by Telefonaktiebolaget Lm Ericsson (Publ) filed Critical Telefonaktiebolaget Lm Ericsson (Publ)
Publication of WO1998047277A1 publication Critical patent/WO1998047277A1/en

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Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q11/00Selecting arrangements for multiplex systems
    • H04Q11/04Selecting arrangements for multiplex systems for time-division multiplexing
    • H04Q11/0428Integrated services digital network, i.e. systems for transmission of different types of digitised signals, e.g. speech, data, telecentral, television signals
    • H04Q11/0435Details
    • H04Q11/045Selection or connection testing arrangements
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M11/00Telephonic communication systems adapted for combination with other electrical systems
    • H04M11/04Telephonic communication systems adapted for combination with other electrical systems with fire, police, burglar, or other alarm systems
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q2213/00Indexing scheme relating to selecting arrangements in general and for multiplex systems
    • H04Q2213/13092Scanning of subscriber lines, monitoring
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q2213/00Indexing scheme relating to selecting arrangements in general and for multiplex systems
    • H04Q2213/13103Memory
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q2213/00Indexing scheme relating to selecting arrangements in general and for multiplex systems
    • H04Q2213/13162Fault indication and localisation
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q2213/00Indexing scheme relating to selecting arrangements in general and for multiplex systems
    • H04Q2213/13163Fault alarm
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q2213/00Indexing scheme relating to selecting arrangements in general and for multiplex systems
    • H04Q2213/13176Common channel signaling, CCS7
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q2213/00Indexing scheme relating to selecting arrangements in general and for multiplex systems
    • H04Q2213/13204Protocols
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q2213/00Indexing scheme relating to selecting arrangements in general and for multiplex systems
    • H04Q2213/13209ISDN
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q2213/00Indexing scheme relating to selecting arrangements in general and for multiplex systems
    • H04Q2213/13296Packet switching, X.25, frame relay
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q2213/00Indexing scheme relating to selecting arrangements in general and for multiplex systems
    • H04Q2213/13345Intelligent networks, SCP

Abstract

A system for transmitting a detected alarm signal from a remote monitoring system (11) having at least one sensor (14), to a central monitoring facility (15). The system comprises a detector (12) for detecting a signal generated by said sensor (14), a service node (3, 19) provided in a public telephone network (1) and having a service database (21) containing message identifiers and associated call destination addresses, and first connection set-up means (3, 12, 13) for setting-up a first connection-oriented communication channel between said detector (12) and the service node (3, 19). Access means (20) are provided for accessing the service database (21) to determine a call destination address corresponding to a message identifier received at the service node (3, 19) in connection with said communication channel. Second connection set-up means (3, 16, 17) are provided for setting-up a second-connection oriented communication channel between the service node (3, 19) and said destination address, and communicating means (12, 13, 3, 16, 17) are provided for communicating the detected signal, or an indication thereof, to a central monitoring facility (15) provided at said destination address, via said two connection oriented communication channels. The two connection-oriented communication channels use a D signalling channel of the ISDN user-network interface of the telephone network (1).

Description

MONITORING SYSTEM AND METHOD

Field of the invention

The present invention relates to a monitoring system and method and more particularly, though not necessarily, to such a system and method which make use of a public switched telephone network.

Description of the prior art

It is known to monitor multiple alarm systems, for example located at individual homes or business locations, from a central monitoring facility. Examples of alarm systems which may be monitored in this way are burglar alarm systems and liquid container level alarm systems. In a similar way, a central monitoring facility may be used to monitor other remotely sensed parameters such as electricity and water consumption. Examples of sensors which may be used in alarm/detection systems include glass break sensors, magnetic contacts, movement alarms, cameras, noise detectors, smoke/fire/fiame detectors, water level sensors etc.

A common means of reliably and rapidly transferring alarm signals from a remote site to a central monitoring facility is to make use of a telephone line of a telephone network such as a Public Switched Telephone Network (PSTN) using the Integrated Services Digital Network (ISDN) user-network interface. If an alarm signal is detected at a remote site, an automatic dialling unit of the alarm system at the site dials a pre-stored telephone number (B-number) which is a number allocated to the central monitoring facility. This initial communication is carried by an ISDN signalling channel. The telephone number allocated to the remote site (A-number) is carried over the signalling channel to the central monitoring facility. If an ISDN communication channel is available, a connection between the remote alarm system and the monitoring facility is made and the monitoring system transmits an appropriate message, via the PSTN, to the central monitoring facility. Typically, the central monitoring facility has a receiver which automatically generates, for example, a visual indication that an alarm signal has been received and an identification of the remote site (made on the basis of the transmitted A-number). A problem with monitoring systems of the type described above, arises for example when the subscriber telephone number (B-number) of the central monitoring facility is changed. In such a circumstance, it becomes necessary to visit all of the sites where alarm/monitoring systems are installed to re-programme the automatic dialling units with the new B-number. A further problem is that the number of alarm calls which the monitoring facility can receive at any one time is severely limited. For example, if the monitoring facility has a single telephone line to the exchange of the PSTN which utilises ISDN, then the number of calls which can be carried by that line is restricted to two. If the operator of the monitoring facility requires further lines to provide more capacity, then this adds to his costs.

Summary of the invention

It is an object of the present invention to overcome or at least mitigate the above noted disadvantages of prior art monitoring systems and methods. In particular, it is an object of the present invention to provide monitoring systems and methods which allow for simple and dynamic re-programming and re-routing of signalling data and which allow for increased signalling capacity.

According to a first aspect of the present invention there is provided a method of transmitting a detected signal from a remote monitoring system, having at least one sensor, to a central monitoring facility, the method comprising the steps of: detecting a signal generated by said sensor; setting-up a connection-oriented communication channel between the remote monitoring system and a service node of a telecommunication network, said communication channel using a signalling channel of the telecommunication network; accessing a service database, provided at the service node, containing message identifiers and associated destination addresses, to determine a destination address corresponding to a message identifier received at the service node in connection with said communication channel; and communicating the detected signal, or an indication thereof, to a central monitoring facility provided at said destination address via said connection oriented communication channel and said service node. By utilising a service database located in the telecommunication network to route signals from remote monitoring systems to a central monitoring facility, the present invention makes it possible to easily and quickly reprogram destination addresses as this can be done within the telecommunication network, i.e. at the service database. Furthermore, the use of such a database also makes it possible to redirect signals in the event that a primary destination address is unobtainable.

A further significant advantage of embodiments of the present invention is that, as the detected signal is conveyed over a communication channel provided on a signalling channel of the telecommunication network, the signal can be carried even when the remote monitoring system, or the central monitoring facility, is "busy", i.e. is engaged in a conventional telephone call. Moreover, it is possible to create a plurality of such communication channels simultaneously over the same signalling channel, such that the central monitoring facility may receive monitoring signals from different remote monitoring systems, effectively simultaneously.

Preferably, the service node comprises an intelligent network having storage means for storing the service database. More preferably, the service node comprises an exchange, coupled to the intelligent network, and arranged to route messages to said determined destination address.

Preferably, the service database is accessed using a subscriber address allocated to the remote monitoring system and which is transmitted to the service node. The subscriber address may be for example the subscriber's "A-number". More preferably, the message identifier used to access the service database comprises a conveyed subscriber address and an alarm identifier (i.e. alarm type) generated by the remote monitoring system.

Preferably, the telecommunication network of the present invention is a public switched telephone network. More preferably, said signalling channel is a D signalling channel of the ISDN protocol. This allows the alarm message to be conveyed without necessarily opening a user traffic channel. Preferably, the method comprises setting up a second connection oriented communication channel between the service node and the central monitoring facility. More preferably, both said first and said second connection oriented communication channels use a signalling channel of the telecommunication network. The first and second connection oriented communication channels may be in accordance with the X-25 communications protocol. More preferably, the remote monitoring facility, the service node, and the central monitoring facility, all have X-25 protocol handling layers.

Preferably, at least one of the first and second connection-oriented communication channel is set-up via a land line of the telecommunication network.

The destination addresses contained in the service database may be, for example, phone numbers, facsimile numbers, e-mail addresses etc.

The method of the present invention may be used to communicate alarm signals from the remote monitoring system to the central monitoring facility. Alternatively, the transmitted monitoring signal may comprise other detected information such as a reading from an electricity or water meter.

The method of the present invention may comprise initiating a communication between the central monitoring facility and the remote monitoring system from the central monitoring facility.

According to a second aspect of the present invention there is provided apparatus for transmitting a detected signal from a remote monitoring system, having at least one sensor, to a central monitoring facility, the apparatus comprising: a detector for detecting a signal generated by said sensor; a service node provided in a public telecommunication network and having a service database containing message identifiers and associated destination addresses; connection set-up means for setting-up a first connection-oriented communication channel between said detector and the service node, the communication channel using a signalling channel of the telecommunication network; access means for accessing the service database to determine a destination address corresponding to a message identifier received at the service node in connection with said communication channel; and communicating means for communicating the detected signal, or an indication thereof, to a central monitoring facility provided at said destination address, via said connection oriented communication channel and the service node.

Brief Description of the Drawings

Figure 1 shows a block diagram of a public telecommunication network providing a remote alarm monitoring service; and

Figure 2 shows a flow-diagram illustrating the operation of the service provided by the network of Figure 1.

Detailed Description of Embodiments

With reference to Figure 1 , a public switched telephone network 1 has a local telephone exchange 2 connected to a transit exchange 3 via a trunk line 4. Both of these exchanges 2,3 may additionally be connected to other exchanges but these connections are not show in the Figure in the interest of simplicity. Both exchanges are connected to a multiplicity of respective "concentrators" 5,6, only two of which are shown in the Figure. The concentrators 5,6 act as multiplexers/demultiplexers between individual telephone subscriber lines 7,8 and one or more high capacity lines 9,10 connecting the concentrators 5,6 to the respective exchanges 2,3.

A first of the subscriber lines 7 connects to a home or business premises 11 , where a burglar alarm monitoring system 12 is connected to the subscriber line 7 via a modem 13. The monitoring system has a number of sensors 14 (again only one sensor is shown in the Figure) which may be for example pressure sensors, infra-red sensors, or door entry sensors.

The second subscriber line 8 connects to a central monitoring facility 15 which is typically a premises of a security company. A modem 16 connects a computer 17 provided at the facility to the subscriber line 8. The computer 17 is also connected to a video display unit (VDU) 18.

The public switched telephone network 1 , and the modem connections 13,16, are arranged to communicate using the known Integrated Services Digital Network (ISDN) user-network interface. ISDN provides three different communication channels between the subscribers (i.e. modems 13,16) and the network 15, namely two 64 kbit/s B-channels which can be used independently to provide respective circuit switched user data traffic channels, and a single 16 kbit/s D-channel which is conventionally used to convey signalling data such as an incoming call alert (in combination these channels are referred to as having a 2B+D structure). Signalling data is typically formatted for transmission according to the International Telecommunications Union (ITU) X-31 standard and occupies 6.4 kbits/s of the D- channel. This leaves 9.6 kbits/s unused on the D-channel.

Figure 1 illustrates a so-called Intelligent Network (IN) 19 which is connected to the transit exchange 3 and which may be provided by one or more printed circuit boards, with appropriate operating software, in the transit exchange 3. Hereafter, the transit exchange 3 and the IN 19 are referred to in combination as a Service Node. It will be understood that other INs may be connected to the same transit exchange and which provide services additional to that which is the subject of the present discussion.

The IN 19 performs the function of a Switching Control Point (SCP) 20 and a Sevice Data Point (SDP) 21 as will be described below. The transit exchange 3 itself contains a Switching Service Point (SSP) which provides switching control for the exchange. The SSP, SCP, and SDP interfaces are defined in by respective ITU specifications. In the event that the SSP receives notification of a subscriber call or message which has a destination address containing some predefined prefix, the SSP enters into a communication with the IN 19 using a Signalling Control Connection Part (SCCP) based signal such as an Advanced Intelligent Network (AIN) based signal.

Consider now that a sensor 14 of the alarm monitoring system 12 is triggered. This is detected by the system 12 which responds by automatically initiating a call to the PSTN 1 via the modem 13. More particularly, the system 12 and modem 13 set-up a connection on the ISDN D-channel using the ITU defined X-25 communication protocol which utilises packet switched data transmission. This connection extends from the modem 13 to the Service Node 3,19. The endpoint of the communication channel, i.e. an entry point from the SSP to the IN 19 at the Service Node, is defined by a telephone number prestored in the memory of the system 12 or modem 13. An alarm message is transmitted from the alarm monitoring system 12 to the Service Node 3,19 and which contains, inter alia, an alarm identifier which identifies the particular sensor which triggered the alarm.

The prestored number and a subscriber A-number are "bound" with the communication and are transmitted to the Service Node 3,19. The A-number is an identifier attached to the entry point of the subscriber line 7 into the concentrator 5, typically the telephone number of the subscriber line.

The SDP 21 (introduced above) contains a centralised call-routing database which is accessed by the SCP 20 when the SSP of the Service Node 3,19 receives a communication which it recognises as having been made to the prestored number. In response to receipt of the A-number and the alarm identifier from the SCP 20, the SDP 21 returns a routeable formatted directory number (i.e. a destination number or B-number) to the SSP via the SCP 20. In the example of Figure 1 , the B-number is the telephone number of the central monitoring facility 15. The alarm message, together with the A-number, is then forwarded to the monitoring facility 15 over the ISDN D-channel using the X-25 protocol. It is noted here that the SSP acts either as a call or a message (i.e. data packet) router depending upon the format of the information received from the alarm system or the format required for transmitting to the central monitoring facility.

The computer 17 at the monitoring facility 15 is arranged upon receipt of the message and the A-number to display on the VDU 18 an indication that an alarm has been received, the location where the alarm was initiated (determined from the received A-number), and if appropriate the alarm type conveyed in the message. The centralised message-routing database of the SDP 21 typically contains a set of different B-numbers which are returned in dependence upon the received A-number number and the alarm identifier. For example, the database may have the following structure:

Figure imgf000010_0001

It will be appreciated that various modifications may be made to the above described embodiment without departing from the scope of the present invention. For example, rather than initiating a communication from the remote system, a communication may be initiated from the central monitoring facility. This may be used, for example, to allow an electricity supply company to obtain electricity meter readings from individual households/premises. Whilst the above embodiment concerns a monitoring system connected directly to a subscriber line via a modem, an alternative arrangement involves coupling the system to the line (or the modem) via a data network such as a Local Area Network (LAN) or a Locally Operated Network (LON).

Whilst the connection between the Service Node and the central monitoring facility has been described above as involving X-25 over ISDN, the connection may be made using only an X-25 connection where this is available. Some other appropriate data transmission protocol may also be used.

Claims

Claims
1. A method of transmitting a detected signal from a remote monitoring system, having at least one sensor, to a central monitoring facility, the method comprising the steps of: detecting a signal generated by said sensor; setting-up a connection-oriented communication channel between the remote monitoring system and a service node of a telecommunication network, said communication channel using a signalling channel of the telecommunication network; accessing a service database, provided at the service node, containing message identifiers and associated destination addresses, to determine a destination address corresponding to a message identifier received at the service node in connection with said communication channel; and communicating the detected signal, or an indication thereof, to a central monitoring facility provided at said destination address via said connection oriented communication channel and said service node.
2. A method according to claim 1 , wherein the service node comprises an intelligent network having storage means for storing the service database.
3. A method according to claim 2, wherein the service node comprises an exchange, coupled to the intelligent network, and arranged to route messages to said determined destination address.
4. A method according to any one of the preceding claims, wherein the service database is accessed using a subscriber address allocated to the remote monitoring system and which is transmitted to the service node.
5. A method according to claim 4, wherein the subscriber address is the subscriber's "A-number".
6. A method according to claim 4 or 5, wherein the message identifier used to access the service database comprises a conveyed subscriber address and an alarm identifier generated by the remote monitoring system.
7. A method according to any one of the preceding claims and comprising setting up a second connection oriented communication channel between the service node and the central monitoring facility
8. A method according to claim 7, wherein both said first and said second connection oriented communication channels use a signalling channel of the telecommunication network.
9. A method according to any one of the preceding claims, wherein the telecommunication network is a public switched telephone network and said signalling channel is a D signalling channel of the ISDN protocol.
10. A method according to claim 7, wherein the first and second connection oriented communication channels use the X-25 communications protocol.
1 1 . A method according to claim 7 or 10, wherein at least one of the first and second connection-oriented communication channels is set-up via a land line of the telecommunication network.
12. Apparatus for transmitting a detected signal from a remote monitoring system (1 1), having at least one sensor (14), to a central monitoring facility (15), the apparatus comprising: a detector (12) for detecting a signal generated by said sensor (14); a service node (3,19) provided in a public telecommunication network (1 ) and having a service database (21 ) containing message identifiers and associated destination addresses; connection set-up means (3, 12, 13) for setting-up a first connection-oriented communication channel between said detector (12) and the service node (3,19), the communication channel using a signalling channel of the telecommunication network
(1 ); access means (20) for accessing the service database (21 ) to determine a destination address corresponding to a message identifier received at the service node (3, 19) in connection with said communication channel; and communicating means (12,13,3,16,17) for communicating the detected signal, or an indication thereof, to a central monitoring facility (15) provided at said destination address, via said connection oriented communication channel and the service node (3,19).
PCT/FI1998/000340 1997-04-16 1998-04-16 Monitoring system and method WO1998047277A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
FI971601 1997-04-16
FI971601A FI971601A0 (en) 1997-04-16 1997-04-16 Science the Alarm oevervakningssystem Science foerfarande

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AU70448/98A AU7044898A (en) 1997-04-16 1998-04-16 Monitoring system and method

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002023882A1 (en) * 2000-09-14 2002-03-21 Sonera Oyj Alarming system
EP1357762A1 (en) * 2002-04-26 2003-10-29 Siemens Aktiengesellschaft Communication system with automatic messaging to a subscriber of a subscriber line functionality failure
FR2859589A1 (en) * 2003-09-05 2005-03-11 France Telecom Surveillance zone remote surveillance method having zone/centre digital word interface links with bridge assembly links virtual circuit/platform connected detecting digital word transmission loss

Citations (4)

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Publication number Priority date Publication date Assignee Title
WO1994022262A1 (en) * 1993-03-23 1994-09-29 Jan Ruus Alarm system
US5444760A (en) * 1993-12-28 1995-08-22 At&T Corp. Routing of special emergency calls
WO1996015633A1 (en) * 1994-11-11 1996-05-23 TELEKONAKTIEBOLAGET L M ERICSSON (publ) System for subscriber administration in telecommunication network
US5646987A (en) * 1994-12-22 1997-07-08 Lucent Technologies Inc. Dynamic reallocation of calls to agent groups

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1994022262A1 (en) * 1993-03-23 1994-09-29 Jan Ruus Alarm system
US5444760A (en) * 1993-12-28 1995-08-22 At&T Corp. Routing of special emergency calls
WO1996015633A1 (en) * 1994-11-11 1996-05-23 TELEKONAKTIEBOLAGET L M ERICSSON (publ) System for subscriber administration in telecommunication network
US5646987A (en) * 1994-12-22 1997-07-08 Lucent Technologies Inc. Dynamic reallocation of calls to agent groups

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN, Vol. 97, No. 5; & JP,A,09 023 287 (NIPPON TELEGR & AMP, et al.) 21 January 1997. *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002023882A1 (en) * 2000-09-14 2002-03-21 Sonera Oyj Alarming system
EP1357762A1 (en) * 2002-04-26 2003-10-29 Siemens Aktiengesellschaft Communication system with automatic messaging to a subscriber of a subscriber line functionality failure
FR2859589A1 (en) * 2003-09-05 2005-03-11 France Telecom Surveillance zone remote surveillance method having zone/centre digital word interface links with bridge assembly links virtual circuit/platform connected detecting digital word transmission loss

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FI971601A0 (en) 1997-04-16
AU7044898A (en) 1998-11-11
FI971601D0 (en)

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