WO1991013510A1

WO1991013510A1 - Communications network and communications device

Info

Publication number: WO1991013510A1
Application number: PCT/GB1991/000250
Authority: WO
Inventors: Stephen Randall; David Edward John Crisp; Neil George Flint
Original assignee: Eden I.P. Limited
Priority date: 1990-02-20
Filing date: 1991-02-19
Publication date: 1991-09-05
Also published as: GB9003745D0

Abstract

A communications network comprising an electronic mail terminal and a conventional telephone sharing a single telephone line is disclosed. The ambiguity as to which device should answer an incoming call is conventionally addressed by a front end switch which can discriminate between data and voice calls. In the present invention, the ambiguity is addressed by arranging for all calls to the electronic mail device to go to a server, which is intermittently polled by the electronic mail device. Consequently, any call on the line will be a voice call for the telephone.

Description

COMMUNICATIONS NETWORK AND COMMUNICATIONS DEVICE

Field of the Invention

This invention relates to a communications network and a communications device and in particular to such a network and device for handling electronic mail.

Description of the Prior Art

Electronic mail systems are well known. Generally, they comprise a computer or terminal connected either to a dedicated data line or, in some cases, to the conventional telephone system. In the latter case, there are drawbacks if the recipient terminal shares a line with a conventional telephone since the caller's equipment, at least in an analog system, cannot inform the recipient's equipment whether the electronic mail device or the telephone should answer.

The conventional solution is to provide a front end switch which responds to preliminary data signals from the caller's data equipment to route the incoming call to the terminal. In the absence of any data identifying signal, the front end switch assumes the signal is a voice signal and routes the call to the telephone. The front end protocol is, however, time consuming and inconvenient to the user who often perceives the extra layer of machine interference as hampering an otherwise reasonably transparent communications medium. For example, it necessitates the answering of a voice call by the front end switch even if the desired recipient is absent This is inconvenient to the caller, who has to pay for the call but cannot be returned to, for example, the PBX (Private Branch Exchange) serving the user telephoned.

Object of the Invention

The aim of the present invention is to provide a communications network and a communications device using a message handling approach which overcomes these drawbacks.

SUBSTITUTE SHEET Statement of the Invention

According to a first aspect of the present invention, a communications network comprises a first communications device and a second communications device, each device sharing a single voice/data communications line, wherein the first communications device is arranged to be unable to take the line off-hook in response to an incoming call but to receive voice/data by the procedure of polling a server, the voice/data for final receipt by the first communications device being routed to the said server.

This construction achieves the advantage that there is never any ambiguity as to whether an incoming call is for the first or the second communications device. It is always for the second device. Consequently, the user regards that second device as uncompromised by having to share its line with the first communications device. It therefore removes the need for separate dedicated lines, eliminating the need for extra cabling at the end user. Further, callers no longer have to pay for calls that go unanswered, as they would do if their call were answered by a front end switch in the absence of the person sought.

In a further embodiment, a communications network as described above is such that the second communications device is operable to take the line off-hook in response to a line signal, after which a subsequent line signal is operable to activate the first communications device into a mode whereby the first communications device can receive voice/data. The advantage of this approach is that it allows direct real time communication between a pair of first communication devices.

Preferably, the second communications device is a telephone and the voice/data communications line a conventional telephone line. Consequently, the present invention can be implemented in virtually all existing offices without the need for extra cabling.

According to a further aspect of this invention, a communications device is proposed which satisfies the requirements of the first communications device as specified above. Preferably, it automatically polls the server at regular intervals, so providing the user with a reasonably up to date account of any messages for him or her. Such a communications device may be arranged to cease communicating with the server if the user starts to use the second communications device. The advantage of this is that it preserves for the user the priority of the second communications device, rendering it transparent, in so far as nothing appears to get in the way of it.

In a particular embodiment, the communications device comprises a visual display screen, a stylus, a digitising means overlaying, underlying or integral to the screen to provide a signal indicative of the position of the stylus relative to the digitising means to control the driver of the screen, whereby what is displayed on the screen when the stylus is moved across the surface of the screen corresponds to what would appear if the stylus were a pen and the screen were paper. The advantage of this approach is that it is a particularly user friendly form of hardware.

Brief Description of the Drawings

The invention will now be described with reference to the accompanying drawings in which Figure 1 schematically depicts a communications network in accordance with the present invention,

Figure 2 schematically depicts a communications device in accordance with the present invention.

Detailed Description

Turning to Figure 1, a telephone handset 2 is connected via a line 6 to a data terminal communications device 1 (illustrated in Figure 2 and discussed in detail later on). The data terminal 1 is powered from a mains supply (not shown) and is connected to subscriber line 5 which itself connects to PSTN 4 (Public Switched

Telephone Network) . To the PSTN 4 is also connected a bundle of subscriber lines 7 terminating in PBX 8 (Private Branch Exchange). To the PBX are connected a server 9 and a further data terminal communications device 3, to which a telephone handset 4 is connected via line 10. Server 9 and device 3 may be on separate lines within the bundle of lines 7.

When the user of telephone 2 wants to telephone the user of telephone 4, he simply picks up the handset and dials telephone 4 in the conventional way. Conversely, when a message is to be sent from data terminal 1 to data terminal 3, the user of data terminal 1 inputs the information to be transferred to terminal 1 and authorises the message to be sent to the required addressee, in this case the server 9. In practice, the user of data terminal 1 may input to that terminal 1 a multi-digit dialing number unique to terminal 3.

It will be appreciated that the implementation of this using conventional techniques, for example a conventional personal computer, a data modem and communications software, is commonplace in this art and within the design compass of an engineer skilled in this art. Specific details of this aspect of the implementation of the invention are therefore omitted in the interests of brevity.

On authorisation, a modem (not shown) integral to the data terminal 1 takes the line 5 off-hook, i.e. to an active state. It sends the data to the recipient server 9, via a central exchange (not shown) and then via PBX 8 using conventional telephone switching procedures. The switching and data communications techniques that may be used will be well known to those in the art and will not be further described herein. It may be noted, however, that the present approach is fully compatible with data transmission using store and forward packet switching techniques, as well as international message handling standards such as CCITT Signalling System No.7.

The server 9 is an Intel 80286 microprocessor based server comprising hard disk storage sufficient to accommodate the expected memory demands that will be made on it . Data terminal 3 polls the server 9 on the manual request of it's user or at fifteen minute intervals for any messages specifically for it. It will be appreciated that there are a variety of techniques for flagging incoining mail to server 9 with tags that identify the ultimate recipient.

The server provides the data to terminal 3 on polling, the data then residing in the internal memory of the terminal 3. Conventionally, the server transmits only a copy of the data it has received. Consequently, if the user of terminal 3 should take the telephone 4 off-hook or receive a voice call, the data transmission will be aborted, but can be retried after a short interval. The user may then display the data and manipulate it in any way prescribed by the software resident in the internal memory of data terminal 3. He may, for instance, choose to annotate it or amend it, or combine it with other data documents on his system, and then send it back to data terminal 1.

In addition to the procedure outlined above, the data terminals 1 and 3 can communicate directly with one another. The procedure for this would be for the user of telephone 2 to call telephone 4; once the loop has been established by the recipient taking the call, the data terminal 1 can be operated to transfer data to terminal 3, with terminal 3 rendered receptive to data receipt by a short preliminary audio tone before transfer. During data transfer, no voice signals would be transferred. It will be appreciated by those skilled in the art that the precise details of the signalling adopted will depend on the prevailing protocols and the nature of the signalling system used.

Referring now to Figure 2, a display means 30, preferably comprising a LCD type display, is shown forming part of a data terminal communications device 1. The input means for the device 1 comprises an electromagnetic induction digitising mat or tablet 20 underlying the display 30, together with an electromagnetic stylus 40. The digitising mat 20 comprises an electrically conducting grid with conductors running parallel to an X-axis, overlaying a similar grid with conductors running parallel to a Y-axis. The stylus 40 comprises an energisable coil which can be excited with alternating current . The amplitude of the voltages induced in the conductive grids provide an indication of the position of the stylus relative to the Cartesian co-ordinate system defined by the X and Y axes.The detailed operation of this form of digitiser is well known in this field. Further reference may be made, for example, to US 4570033. Using this digitising system, the user can easily and naturally input graphical information for storage and subsequent, although nearly immediate, display by the apparatus.

It will be appreciated that a variety of components, e.g. a power supply, is necessary for the functioning of the apparatus and will have to be present in the apparatus but these are not expressly detailed here in the interests of brevity and clarity.

The stylus 40 is shown touching the LCD 30 and electrical signals indicative of the position (X Y Co-ordinates) at which it contacts the LCD 30 are supplied to an A to D converter 11 feeding a data path or system bus 15. A CPU 12 is connected for bi-directional data flow to the bus 15, as is a RAM 17. A ROM 18 is also connected to bus 15, being programmed with the operating system for the apparatus, including the telecommunications procedures. CPU 12 provides all control signals via bus 15. RAM 17 stores the user input (e.g all messages sent, together with any annotations the terminal user might wish to make to data received and displayed) RAM 17 may be an EEPROM or magnetic bubble memory. CPU 12 may be a microprocessor such as the 80286 manufactured by Intel Corporation. In addition there is provided a data modem 19 connected to bus 15 for sending and receiving serial data information. A display driver 14 is connected to bus 15 and drives the display 20.

In use, the user may, for example, have supplied to his or her terminal 3 a brief memo from the user of terminal 1. This would be sent via the modem 19 associated with terminal 1 to server 9 and then to terminal 3 when polled by terminal 3. The memo would be stored in RAM 17 and cause an appropriate control signal to issue from the driver 14 to result in an appropriate image to be displayed on the display 20 on the user's request The user may then input some annotations to the memo using the stylus. The manuscript annotations appear displayed by the display 20 immediately underneath the points on the LCD 30 they would have appeared on were the LCD 30 a piece of paper and the stylus 40 a pen. The composite document comprising original memo plus annotations is stored in RAM 17 and a copy may be sent via modem 19 in terminal 3 back to terminal 1.

Claims

1. A communications network comprising a first communications device and a second communications device, each device sharing a single voice/data communications line, wherein the first communications device is arranged to be unable to take the line off-hook in response to an incoming call but to receive voice/data by the procedure of polling a server, the voice/data for final receipt by the first communications device being routed to the said server.

2. A communications network as claimed in Claim 1 wherein the second communications device is operable to take the line off-hook in response to a line signal, after which a subsequent line signal is operable to activate the first communications device into a mode whereby the first communications device can receive voice/data.

3. A communications network as claimed in either Claim 1 or Claim 2 wherein the second communications device is a telephone.

4. A communications network as claimed in any preceding claim wherein the voice/data communications line is a conventional telephone line.

5. A communications device arranged to operate as the first communications device as claimed in any preceding claim.

6. A communications device as claimed in Claim 5 arranged to poll the server automatically at predetermined intervals.

7. A communications device as claimed in Claim 6 arranged to cease using the line should the second communications device be used.

8. A communications device as claimed in Claim 5, 6 or 7 comprising a visual display screen, a stylus, a digitising means overlaying, underlying or integral to the screen to provide a signal indicative of the position of the stylus with respect to the digitising means to control the driver of the screen, whereby what is displayed on the screen when the stylus is moved across the surface of the screen corresponds to what would appear if the stylus were a pen and the screen were paper.