GB2329297A

GB2329297A - An ISDN Communication System

Info

Publication number: GB2329297A
Application number: GB9719301A
Authority: GB
Inventors: Lawrence Atkinson
Original assignee: OPTIMA TELECOMMUNICATIONS Ltd
Current assignee: OPTIMA TELECOMMUNICATIONS Ltd
Priority date: 1997-09-11
Filing date: 1997-09-11
Publication date: 1999-03-17
Also published as: GB9719301D0

Abstract

An ISDN communication system (1) comprising an ISDN line (2,3), connection means including at least one analogue port (5,6) and a data port (7), at least one non-ISDN piece of equipment connected to the data port (7) for connecting the non-ISDN piece(s) of equipment to the ISDN line via the connection means, a non-ISDN analogue control unit (8) connected to the analogue port(s) (5,6) for receiving analogue information transmitted over the ISDN line (2,3), and a plurality of analogue extension devices connected to the analogue control unit (8). The analogue control unit (8) is also connected to the data port (7) for controlling the supply of analogue information, received at the control unit from the ISDN line, to the analogue extension devices. The invention also relates to an analogue control unit.

Description

An ISDN Communication System This invention relates to an ISDN (Integrated Services Digital Network) communication system which enables the connection of an analogue control unit1 such as a PBX, to an ISDN line for supporting ISDN services.

In a conventional ISDN system, an ISDN line is connected to a non-ISDN piece of equipment, such as a PC, via a terminal adaptor (TA). Alternatively the ISDN line may be connected to a LAN (local area network) via a bridge router. In either case, connection means, in the form of a TA or bridge router, connects an ISDN line to at least one non-ISDN pieces of equipment to enable the latter to communicate with a network via the ISDN line. Known TAs are provided with at least one analogue port to enable the connection thereto of at least one conventional PSTN device, such as an analogue telephone or fax machine. However the conventional PSTN device or devices is or are not able to take advantage of the specialised digital services available over ISDN lines. Thus, for example, if a PBX is connected directly to an analogue port of a TA, it is not possible for the PBX automatically to divert incoming calls to a desired analogue extension telephone by making use of information fed to the TA from the ISDN.

With a conventional digital communication system, a digital exchange unit is connected to a number of digital extension telephones (or to analogue extension telephones if the digital exchange unit is provided with a digital-toanalogue converter). If the digital exchange unit is connected to an ISDN line, it is able to divert calls automatically to any desired extension telephone in dependence on the digital signals passed along the ISDN line. However a disadvantage of such a digital communication system is that the digital exchange unit and digital extension telephones (or digital-to-analogue converter) are relatively expensive compared with their analogue equivalents.

An aim of the present invention is to connect a relatively inexpensive analogue control unit to an ISDN line and to control the forwarding of incoming calls on the ISDN line to analogue telephone extensions connected to the control unit.

According to one aspect of the present invention there is provided an ISDN communication system comprising an ISDN line, connection means including at least one analogue port and a data port, at least one non-ISDN piece of equipment connected to said data port for connecting the non-ISDN piece(s) of equipment to the ISDN line via the connection means, a non-ISDN analogue control unit connected to the said analogue port(s) for receiving analogue information transmitted over the ISDN line, and a plurality of analogue extension devices connected to the analogue control unit, characterised in that the analogue control unit is also connected to the data port for controlling the supply of analogue information, received at the control unit from the ISDN line, to the analogue extension devices.

Conveniently the analogue control unit comprises a PBX. If two ISDN lines are connected to the connection means and the latter has two analogue ports, the analogue control unit may comprise a PBX supporting two sets of eight extension devices. The extension devices may, for example, comprise analogue telephones and/or fax machines.

The connection means may comprise a terminal adaptor.

Alternatively, if there are a number of said non-ISDN pieces of equipment connected in a network, e.g. a local area network (LAN), the connection means may comprise a bridge router.

According to another aspect of the present invention there is provided an analogue control unit, e.g. a PBX, having outlet means to enable a plurality of analogue extension devices to be connected directly or indirectly to the control unit for control thereby, and first inlet means for connection to an analogue part of connection means connected to an ISDN line, characterised in that the control unit further comprises second inlet means for connection to a data port of the connection means to control the supply of analogue information, inputted to the control unit via the first inlet means, to the analogue extension devices.

The present invention is intended to enable an analogue control unit to be connected to an ISDN network and to be able to take advantage of the special services provided by such a network. In particular, it is possible to make use of the multiple subscriber number (MSN) service which allows incoming calls on the ISDN line to be diverted to a desired analogue extension device, e.g. an analogue telephone, via the analogue control unit without operator intervention. This is achieved by supplying the required information, from the data port of the connection means, to the control unit. Other digital services, such as caller line identity (CLI) can also be made use of. In this way an analogue communication sub-system comprising the analogue control unit and analogue extension devices can enjoy the benefits of a digital communication system but at a considerably cheaper cost. The cost benefit is achieved because analogue extension devices, e.g. analogue telephones, are considerably cheaper to purchase than equivalent digital extension devices or digital exchange units provided with digital-to-analogue converters.

According to a still further aspect of the present invention there is provided an ISDN communication system comprising an ISDN line, connection means having first and second outlet ports, at least one non-ISDN piece of equipment connected to said first outlet port for connecting the non-ISDN piece(s) of equipment to the ISDN line via the connection means, and a plurality of analogue extension devices connected to the second outlet port, characterised in that the connection means includes first link means for supplying analogue information from the ISDN line to the analogue extension devices and second link means for controlling which analogue extension device the analogue information is supplied to in dependence on digital information supplied to the connection means via the ISDN line.

An embodiment of the invention will now be described, by way of example only, with particular reference to the accompanying drawing the sole figure of which schematically represents an ISDN communication system according to the present invention.

The drawing shows an ISDN network 1 having two ISDN lines 2 and 3 connected to a terminal adaptor 4 having two analogue ports 5 and 6 and a data port 7, e.g. an RS232 output, for supplying data along a digital channel to a non ISDN piece of equipment (not shown), such as a PC.

An analogue control unit, in the form of a 2 x 8 extension PBX 8, has two inlet ports 9 and 10 connected to the analogue ports 5 and 6, respectively, by cables 11 and 12. The PBX 8 has a further inlet port 13 connected to the data port 7 of the terminal adaptor 4 by means of a cable 14. Analogue extension telephones (not shown) are connected in series to an outlet 15 of the PBX 8.

In use of the communication system, an incoming voice call on one of the ISDN lines 2, 3 is diverted through the terminal adaptor 4 to the PBX 8 via one of the cables 11,12.

The call is then forwarded with no operator intervention to the desired extension telephone. The forwarding of the call to the desired extension telephone is controlled by the signal received from the data port 7 of the terminal adaptor 4. The necessary switching of the incoming call to the desired extension telephone is software driven. The modifications required to the PBX 8 to enable this control is not described herein but is state of the art to a skilled person in this field. The digital information available at the data port 7 and supplied via the cable 14 to the inlet port 13 can be used to provide other ISDN services such as, for example, caller line identity (CLI), to the various extension telephones. This is all made possible by the computer-telephony integration (CTI) provided by the link cable 14.

Other non-ISDN extension devices, e.g. fax machines, smoke detectors, door entry phones etc., may be connected to the available PBX extensions in addition to, or as an alternative to, extension telephones. Furthermore a conventional telephone line (i.e. a non-ISDN line) may be connected to another input (not shown) of the PBX 8.

In other systems, the terminal adaptor may be replaced by a bridge router for connection into a local area network (LAN) or the like.

Instead of having a separate terminal adaptor (or bridge router) and PBX (or other analogue control unit), these devices may be combined in a single unit with the various connections made internally.

Claims

1. An ISDN communication system comprising an ISDN line, connection means including at least one analogue port and a data port, at least one non-ISDN piece of equipment connected to said data port for connecting the non-ISDN piece(s) of equipment to the ISDN line via the connection means, a non-ISDN analogue control unit connected to the said analogue port(s) for receiving analogue information transmitted over the ISDN line, and a plurality of analogue extension devices connected to the analogue control unit, characterised in that the analogue control unit is also connected to the data port for controlling the supply of analogue information, received at the control unit from the ISDN line, to the analogue extension devices.

2. An ISDN communication system according to claim 1, characterised in that the analogue control unit comprises a PBX.

3. An ISDN communication system according to claim 1 or 2, characterised in that two ISDN lines are connected to the connection means which has two analogue ports, and in that the analogue control unit comprise a PBX supporting two sets of eight extension devices.

4. An ISDN communication system according to any one of the preceding claims, characterised in that the connection means comprises a terminal adaptor.

5. An ISDN communication system according to claim 1, characterised in that there are a number of said non-ISDN pieces of equipment connected in a network and in that the connection means comprises a bridge router.

6. An analogue control unit having outlet means to enable a plurality of analogue extension devices to be connected directly or indirectly to the control unit for control thereby, and first inlet means for connection to an analogue part of connection means connected to an ISDN line, characterised in that the control unit further comprises second inlet means for connection to a data port of the connection means to control the supply of analogue information, inputted to the control unit via the first inlet means, to the analogue extension devices.

7. An ISDN communication system comprising an ISDN line, connection means having first and second outlet ports, at least one non-ISDN piece of equipment connected to said first outlet port for connecting the non-ISDN piece(s) of equipment to the ISDN line via the connection means, and a plurality of analogue extension devices connected to the second outlet port, characterised in that the connection means includes first link means for supplying analogue information from the ISDN line to the analogue extension devices and second link means for controlling which analogue extension device the analogue information is supplied to in dependence on digital information supplied to the connection means via the ISDN line.

8. An ISDN communication system constructed and arranged substantially as herein described with reference to, and as illustrated in, the accompanying drawing.