WO1999038312A1

WO1999038312A1 - Computer telephony integrated pbx

Info

Publication number: WO1999038312A1
Application number: PCT/US1999/001791
Authority: WO
Inventors: Otto M. Cenzano
Original assignee: Willowbrook Technologies
Priority date: 1998-01-27
Filing date: 1999-01-27
Publication date: 1999-07-29
Also published as: EP1051836A1; EP1051836A4; JP2002504761A; CA2318541A1; AU2477399A

Abstract

A telephony and data network (figure 1) is achieved by integrating a plurality of signal switching circuits in circuit hub devices. The devices (Hubs) each resemble a typical 10 Base-T, 8 port ethernet hub in size and outward appearance and preferably has an 8 port interface. This interface is constructed and arranged to interconnect to phone lines directed from a standard analog signal handling telephone set, and also from a telephone system central office. It therefore acts as an interface device between these two points in the telephone network. Each Hub provides a signal processing circuit having digital/analog signal converting capability in the form of standard telephone coder-decoder circuits. These Codec circuits are supervised by a digital signal processor which is a part of the signal processing circuit of the Hub. The Hub circuit also provides a general-purpose microprocessor capable of handling LAN communications. The Hub is configured to communicate over a LAN with any standard protocol. Software is written to allow interfacing with common personal computer operating systems and applications.

Description

TITLE : COMPUTER TELEPHONY INTEGRATED PBX

BACKGROUND OF THE INVENTION

FIELD OF THE INVENTION:

This invention relates generally to telephony networks, and more particularly to such a network integrated with computer LAN systems.

DESCRIPTION OF RELATED ART:

The following art defines the present state of this field:

Slavin, U. S. 3,889,063 provides a multiplexed digital data communication system wherein analog signals received from a conventional telephone system having a plurality of channels are multiplexed at a high sampling rate and converted to a series of discrete digital signals in a series of time slots. The system includes data transmission means for substituting data signals for said discrete digital signals in periodically spaced time slots.

The communication system would include a plurality of local stations coupled to a common transmission line to which the series of discrete digital signals is applied, each of the local stations being adapted to demultiplex and convert to analog signals the portion of said discrete digital signal intended for it, and to supply said analog signals to the user. Similarly, the local station can multiplex and digitize user initiated analog signals for application to the transmission line, while the central station has demultiplexing and digital to analog capabilities.

Agricola et al., TJ. S. 4,281,410 provides a circuit arrangement for telecommunications, in particular telephone exchange installations that switch through digitally by time division, having a special coupling network for switching audio-signals to terminal units which, besides the connection network provided for the interchange of speech and data information, sets up the connection between terminal units and audio-signal senders and works digitally.

Duncanson et al., U. S. 4,884,269 provides a method and apparatus for allowing ISDN devices to communicate over an analog telephone line is shown. A first interface (12) accepts ISDN formatted data from an ISDN terminal equipment (TE) device (10), removes the D channel data from the ISDN data, and provides the D channel data to a synchronous modem (14). The modem (14) places onto an analog telephone line (15) a modulated carrier corresponding to the D channel data. The modulated carrier is passed through a telephone switch (16) onto another analog telephone line (17). A second synchronous modem (20) accepts the modulated carrier, demodulates the modulated carrier to recover the data, and provides the data to a second interface (22). The second interface (22) accepts the data from the modem (20), inserts the data into the D channel information is ISDN data stream, and provides the ISDN data stream to an ISDN network termination (NT) device of ISDN switch (24). The result is that two ISDN devices can communicate with each other, even in areas where the local telephone company does not provide ISDN capability and the two devices must communicate with each other using a non-ISDN medium, such as an analog telephone line. Furthermore, and ISDN device can be tested and evaluated for compatibility and operation with ISDN switch without the necessity of having to transport the ISDN device to an area wherein the local telephone company provides ISDN switching capabilities.

Yoshida et al., U. S. 4,922,484 provides an ISDN remote switching unit for accommodating analogue telephone subscriber lines and ISDN digital subscriber lines comprises at least one signal converter for each of the conventional analogue subscriber so that a line signal, an address signal and tone signal of each conventional analogue subscriber are converted into a signaling system of the ISDN digital subscribers line, and a traffic concentrator connected to the signal converter and disposed remote from a host exchange station, whereby the signaling system between the remote station and the host station is unified for both the analogue telephone subscriber and the ISDN digital subscriber. Kagami, U. S. 5,113,396, provides a line interface for ISDN channels converts an analog signaled from an analog communication terminal to digital data and sends the converted digital data to a B-channel of ISDN. The digital data from the B-channel of ISDN is converted to an analog signal and the converted analog signal is then sent to the analog communication terminal.

Steinka et al., U. S. 5,134,611, provides a data communications method and system is provided to facilitate the communication between a plurality of units of data terminal equipment (DTE) connected over communication lines. A first DTE unit is located in a digital network and a second DTE unit is located in either a digital network or in an analog network. When attempting to place a call from the first DTE unit in either a digital network or an analog network, a first call is made to determine the characteristics of the second DTE unit called. If the second DTE unit called returns an indication that it also possesses digital capability, then the call is established. If, however, the indication from the second DTE unit called is that it does not have digital capability, then the first DTE unit places a second call through a modem within a terminal adapter within the system to the second DTE unit. The system is also capable of receiving a call made to the first DTE from outside the digital network. The system also has the capability of establishing an error-free connection between the first DTE and second DTE units.

Fornek et al., U. S. 5,305,312, provides an interface to an integrated service, digital network (ISDN) line for up to two analog dual tone, multifrequency telephones and up to four personal computers or data terminals. A stored program controlled processor controls access to the ISDN line for the analog and digital interface circuits. The processor also provides access to switch-controlled ISDN features for the analog telephones (e.g., call waiting, call hold, etc.).

Grimes et al., U. S. 5,463,623, provides a system combining LAN and telecommunication capabilities to provide a high speed wireless LAN capability and to simultaneously provide wireless ISDN capability within an office. The LAN and ISDN information is communicated over a common transmission medium. The system also allows a user to interconnect wireless ISDN digital terminals to any other ISDN equipment anywhere in a PBX switch system or the public network. The system provides for communication of information between wireless LAN units and ISDN equipment. For example, this function allows a local computer using a local LAN interface to communicate with a remote computer via ISDN switching facilities. Further, the expense of hiding unsightly wiring in an office environment can be avoided, and the cost of moves and rearrangements of equipment can be greatly minimized.

Lynch et al., U. S. 5,515,373, provides a low-cost yet high-performance, moderate bandwidth (up to 2 Mbps) global telecommunications interface to new and existing computers allows high-performance, low-cost telecommunications platforms to support global fax, data, voice, and other data streams in an intuitive way. The telecommunications interface provides a very low-cost solution to international connectivity for a broad class of existing computers while providing high-performance side-area data transfer. Convenient and reliable global communications over the phone line may thus be achieved. From a rudimentary viewpoint, the telecommunications interface provides for an elegant, economical implementation of a fax/data modem. The telecommunications interface provides both a time-division multiplexed interface mode for constant bit rate communications and a packetized interface mode for variable bit rate communications. Multiple streams of digital and/or analog-derived data may be handled simultaneously. DMA and non-DMA interface mode are provided in order to achieve compatibility with a broad range of existing and new computers.

Giovannoni et al., U. S. 5,659,684, provides methods and apparatus for providing virtual local connection of one PC to another PC, a PC to a LAN and from one LAN to another LAN, over a synchronous digital wide area network (effectively enabling a LAN to be extended through a synchronous digital wide area network on a virtual basis), using a PC adapter card that includes an on board Data Service Unit (DSU)/Channel Service Unit (CSU), driven by control means that functions at least in part as a LAN interface emulator. The invention includes methods (and corresponding apparatus) for configuring the PC adapter card under program control; and establishing connectivity between at least one PC and at least one LAN, each separately connected to the network, via a gateway access through the digital wide area network; and for utilizing the PC motherboard microprocessor to run user applications software while simultaneously being able to handle the real time constraints of running packet protocols (e.g., Frame Relay, X.25, SMDS, etc.) using a novel control means.

The subject appears to be similar in construction and method of operation to several of the references. The processing of digital and analog signals in parallel and by conversion from one form to the other in a distributive system is well known. The provision of packetizing of information is also well known. The use of hubs for local interfacing in LANs and the use of interconnected interface circuits, or hubs, in wireless interconnection is also well known. However, the combining of hub techniques in an integrated voice signal and data signal; telephony-computer LAN in the manner taught in this application is novel. The device that makes the present novel network possible, the telephony Hub, described below, is also novel in its ability to provide voice signal processing in that it is compact, inexpensive to produce, quite simple to employ (installation and maintenance) and provides other advantages not found in the prior art.

SUMMARY OF THE INVENTION

The present invention teaches certain benefits in construction and use which give rise to the objectives described below.

The invention provides a new business communications system that melds together telephones and computers into a more integrated, powerful and cost effective system than has been previously conceived. This invention brings together the knowhow of PBX, personal computer data processing, local area networks, intranet, voice, data and multimedia technologies. It replaces current centralized, proprietary, PBX and related systems (ACD, IVR, Predictive Dialing, etc.) Conceptually speaking, current PBX equipment has been relatively unchanged with respect to distributed networking, microprocessor interface, and DSP technology for some time. Personal computers are being used under Windows, Unix, and other known operating systems, but, although these are excellent platforms for general purpose data processing and networking, they are not designed with the efficiencies required for optimal real-time processing and transmission of practical analog signals. Current, proprietary, centralized PBX technologies are expensive and, technologically stagnant. Personal Computer (PC) based systems and PC based interfaces with current PBX devices are waiting for advanced software development in order to implement improved computer-telephony integration.

A primary objective of the present invention is to provide a distributed (physically spread-out) telephony interface network having advantages not taught by the prior art.

Another objective is to provide such a system that is able to complement or replace standard PBX technology.

A further objective is to provide such a system that is cost effective in that it may be expanded without limit as necessary to provide necessary bandwidth and operating speed.

A further objective is to provide a hub-type device for enablement of the network of the invention, the hub-type device being the key component necessary to the success of such a network.

Other features and advantages of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWING

The accompanying drawings illustrate the present invention. In such drawings: FIGURE 1 is a block diagram illustrating a preferred application of the present invention showing a typical installation in a multiple floor office with 2 riser closets per floor, wherein all telephone and computer LAN cables terminate in a riser closet so that the computer LAN hubs and telephony interface hubs in these riser closets are connected to hubs on other floors thereby completing a telephony LAN and an office LAN with signals from both LANs moving between closets over common wires;

FIGURE 2 is a logical flow diagram illustrating the logic steps used in connecting a ringing trunk line in the present invention; and

FIGURE 3 is a block diagram teaching the elements and the element interconnections in a hub type device defining the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is a distributed network of ethernet-like local area network (LAN) hub type devices. The hub type device of the present invention shall be referred to as a telephony interface hub, or simply the "Hub." The Hub is constructed to resemble a typical 10 Base-T, 8 port ethernet hub in size and outward appearance and this is well known in the field of this art. The Hub preferably has an 8 port interface. This interface is constructed and arranged to interconnect to phone lines directed from a standard analog signal handling telephone set, and also from a telephone system central office (CO). It therefore acts as an interface device between these two points in the telephone network. Each Hub provides a signal processing circuit having digital/analog signal converting capability in the form of standard telephone coder-decoder (Codec) circuits. These Codec circuits are supervised by a digital signal processor (DSP) which is a part of the signal processing circuit of the Hub. The Hub circuit also provides a general-purpose microprocessor capable of handling ethernet LAN communications. The Hub is configured to communicate over the LAN with any standard protocol such as TCP/IP. Software is written to allow interfacing with common personal computer (PC) operating systems and applications. The group of software programs that enables communication between the Hubs and PC's is a telecommunications operating system.

The Hubs operate under the telecommunications operating system and therefore are able to naturally connect to all standard network systems, such as the Internet. Because the Hubs are interconnected as a part of the LAN they are able to naturally integrate with a Windows™ (MicroSoft, Inc.) based PC environment to create a physically simple configuration, with operational management through the well-known click and drag techniques.

The Hub is a hybrid device joining telephone line networks having packet switched LAN interfacing, with digital signal processing (DSP) capability. As stated, telephone lines of either CO origination (trunks) or telephone station (set) termination are compatible with the Hub via the Codec. In the preferred embodiment, the DSP device is referred to as a telephony signal processor (TSP). Each Hub provides two TSPs, each having access to four Codec devices. The TSP receives digitized audio signals from the Codec or sends a Codec digitized audio signal for the Codec to convert to analog and transmit to the telephony port. In addition to sending or receiving data from the Codec the TSP is able to process received digitized audio data for voice recognition, DTMF, call progress analysis, and other tasks. Each TSP uses about 1 meg of local random access memory (RAM) and shares 12 to 16 megs of RAM for voice data buffering.

Each TSP's memory contains the programs necessary to process telephony data such as voice recognition, facsimile and modem capabilities, voice synthesis, DTMF recognition and generation, call progress analysis, etc. These program types are well known in the art, so that they shall not be further described here. Information for telephony port configuration, status and support is also maintained in TSP memory.

A command and control processor (CCP) memory contains programs and information necessary to process any change of status of any telephony port as directed by a TSP. It contains all connection and address information to all other TI Hubs, their ports and any PCs or network servers assigned to receive or distribute telephony data. Any scripts or other programmed processing of telephony data is maintained here as well. A telephony data buffer-dictionary (TDD) RAM is used to hold larger amounts of telephony data such as voice mail, auto attendant scripts, connection address information for larger configurations, and so on.

Each communication process involves transactions between a TSP, the CCP, and, if required, the Codec and ethernet interfaces to the telephony data LANs and/or to the CO LAN. The process described here is one of hundreds to thousands, or more, of discrete steps that is handled by this distributed network architecture of Hubs with personal computers, or other types of computers, on a common communication medium such as a LAN, an intranet or the internet. This procedure enables a ringing trunk line to be connected to a specific telephone station set allowing a conversation between users on the system and also between a user and a person outside the system.

As shown in figure 2, the process for connecting a ringing trunk line starts with a status change at a Hub's telephony port which is a process handled by the TSP. Once a telephony port status has changed, a telephony port status table is updated to reflect the port's new state. If the new status is not a ringing trunk line then a specific procedure is initiated to handle this other process. If the new status is a ringing trunk line then the CCP is notified and begins the process of connecting this phone line to allow a telephone conversation. The CCP, after being informed by a TSP of a ringing trunk line condition on a particular telephony port, looks up the connection data from its TDD. This data tells the CCP what procedure to follow when this condition occurs at this telephony port. Other procedures may include an auto attendant script, transfer to an ACD group, send caller information to a tracking procedure at another computer, and other processes. If the telephony ports connection data is defined as connecting this port to a specific telephone station set then the procedure continues, otherwise a different procedure is initiated. The Hub involved is queried concerning the status of the specified station set. If the specified station set is on-hook, that is, the telephone set is hung up and not being used, then it is available to be rung to initiate a telephone conversation. Otherwise the station set is busy and the incoming ringing trunk line is handled by a different procedure, requesting voice mail, sending a Busy Tone, or other process.

When the station set is on-hook it is commanded to ring with a command from the originating Hub to the terminating Hub where the specified station set is located. When the station set is answered, it goes off-hook when a connection is made so as to transmit voice packets to the specified station set and voice packets from the specified station set are sent to the originating line, i.e., a connection is made.

In practice, the office LAN is installed and connected in a manner well known in the art. A telephony LAN connects all telephony Hubs and can connect to one or more telephony servers. Hubs can also connect to the office LAN. This provides complete integration between the office computer and telephone systems as compared with the common method of interconnecting an office LAN to the office PBX through an expensive and restrictive interface hardware/software system.

Therefore, from the above description we find that the present invention is advantageously described as a signal processing apparatus (Hub) comprising a signal processing circuit, as shown in figure 3, providing a plurality of signal ports, preferably eight, for receiving and sending telephony signals, a digital/analog signal converting means of any common type, supervised by a TSP and a general-purpose microprocessor (CCP) capable of handling ethernet communication signals, this device too, being of any common type, the signal processing circuit being configured to communicate over a local area network with a standard LAN based protocol, the apparatus being operated by a software instruction set written to allow interfacing between the apparatus and personal computers. Such a software instruction set would be of any common type capable of being written by those of skill in the art.

Preferably, the signal processing circuit provides two telephony signal processors, each of the processors having access to four Codec devices, the processors receiving digitized audio signals from the Codec devices, the apparatus sending analog signals from the

10 Codec devices to any one of the signal ports. Preferably, each of the telephony signal processors are configured and enabled to process digitized audio data for voice recognition, DTMF, and call progress analysis. Preferably, each of the telephony signal processors provides at least 1 megabit of random access memory and provides at least 12 to 16 megabits of random access memory in a form for sharing for voice data buffering.

The present invention includes a method, as shown in figure 2, for processing a ringing trunk line for connection within a phone system network and this method comprises the following steps of providing a network of discrete distributed telephony signal processing circuits; sensing a change of status at a port of one of the processing circuits; updating a port status table to reflect the port's new status; determining if the status change is due to a ringing trunk line; processing for another status change if the trunk line is not ringing; connecting the ringing trunk line if the trunk line is ringing; getting connection data for the appropriate port from a telephony data dictionary; determining if the port is defined as connecting to a specific station set; processing other connection if no specific station is set; determining if the specific station is on hook if a specific station is set; making a connection if the specific station is on hook; and processing other action if the specific station is off hook.

The invention provides for a communications network, as shown in figure 1, comprising a first local area network including a plurality of a means for data signal processing, such as personal computers, but not limited thereto, interconnected through a plurality of data signal switching hubs, such as standard ethernet interfaces, by a first distributed signal carrying means such as copper wires or optical fiber transmission lines, in such manner that each of the data signal processing means has data signal access to all other of the data signal processing means. A second local area network, similar to the first, includes a plurality of a means for voice signal processing, such as common telephone sets, interconnected through a plurality of voice signal switching hubs, the subject of this application, by a second distributed signal carrying means not unlike the first, in such manner that each of the voice signal processing means has voice signal access to all other of the voice signal processing means. The first and second local area networks are

11 integrated such that data signals originating at any of the data signal processing means may be terminated at any of the voice signal processing means, and voice signals originating at any of the voice signal processing means may be terminated at any of the data signal processing means. Such integration is well known in the art so that it is not further described herein.

The communications network preferably further includes a means, preferably a computer controlled data storage and logic device of any well known type, interconnected with the first local area network by the first distributed signal carrying means, for controlling the destination of each data signal originating on the first local area network, and a means, (telephony server) similar to the above, interconnected with the second local area network by the second distributed signal carrying means, for controlling the destination of each voice signal originating on the second local area network.

The communications network preferably is constructed wherein the first local area network is interconnected with at least one remote data processing network, such as the Internet, so that data signals may be exchanged therewith and wherein the second local area network is interconnected with at least one remote telephony network, such as a telephone utility, so that voice signals may be exchanged therewith.

The communications network preferably is constructed wherein at least one of the first and second local area networks is interconnected with at least one remote data processing network and at least one remote telephony network so that data and voice signals may be exchanged therewith.

While the invention has been described with reference to at least one preferred embodiment, it is to be clearly understood by those skilled in the art that the invention is not limited thereto. Rather, the scope of the invention is to be interpreted only in conjunction with the appended claims.

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Claims

What is claimed is:

A signal processing apparatus comprising a signal processing circuit providing a plurality of signal ports for receiving and sending telephone signals, a digital/analog signal converting means supervised by a digital signal processor and a general- purpose microprocessor capable of handling ethernet-like communication signals, the signal processing circuit being configured to communicate over a local area network with a standard local area network protocol, the apparatus being operated by a software instruction set written to allow interfacing between the apparatus and personal computers.

2. The apparatus of claim 1 wherein the signal processing circuit provides two telephony signal processors, each of the processors having access to four Codec devices, the processors receiving digitized audio signals from the Codec devices, the apparatus sending analog signals from the Codec devices to any one of the signal ports.

3. The apparatus of claim 2 wherein each of the telephony signal processors are configured and enabled to process digitized audio data for voice recognition, DTMF, call progress analysis and caller identification.

4. The apparatus of claim 3 wherein each of the telephony signal processors provides approximately 1 megabit of random access memory and provides approximately 12 to 16 megabits of random access memory in a form for sharing for voice data buffering.

5. A method for processing a ringing trunk line for connection within a phone system network comprising the steps:

A) providing a network of discrete distributed telephony signal processing circuits;

13 B) sensing a change of status at a port of one of the processing circuits;

C) updating a port status table to reflect the port's new status;

D) determining if the status change is due to a ringing trunk line;

E) processing for another status change if the trunk line is not ringing; F) connecting the ringing trunk line if the trunk line is ringing;

G) getting connection data for the appropriate port from a telephony data dictionary; H) determining if the port is defined as connecting to a specific station set; I) processing other connection if no specific station is set; J) determining if the specific station is on hook if a specific station is set; K) making a connection if the specific station is on hook; and

L) processing other action if the specific station is off hook.

6. A communications network comprising: a first local area network including a plurality of a means for data signal processing interconnected through a plurality of data signal switching hubs by a first distributed signal carrying means, in such manner that each of the data signal processing means has data signal access to all other of the data signal processing means; a second local area network including a plurality of a means for voice signal processing interconnected through a plurality of voice signal switching hubs by a second distributed signal carrying means, in such manner that each of the voice signal processing means has voice signal access to all other of the voice signal processing means; the first and second local area networks being integrated through the plurality of voice signal switching hubs such that data signals originating at any of the data signal processing means may be terminated at any of the voice signal processing means, and voice signals originating at any of the voice signal processing means may be terminated at any of the data signal processing means.

7. The communications network of claim 6 further including a means, interconnected with the first local area network by the first distributed signal carrying means, for controlling the destination of each data signal originating on the first local area

14 network, and a means, interconnected with the second local area network by the second distributed signal carrying means, for controlling the destination of each voice signal originating on the second local area network.

8. The communications network of claim 7 wherein the first local area network is interconnected with at least one remote data processing network so that data signals may be exchanged therewith.

9. The communications network of claim 7 wherein the second local area network is interconnected with at least one remote telephony network so that voice signals may be exchanged therewith.

10. The communications network of claim 7 wherein at least one of the first and second local area networks is interconnected with at least one remote data processing network and at least one remote telephony network so that data and voice signals may be exchanged therewith.

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