MXPA00012099A

MXPA00012099A - System and method for communicating voice and data over a local packet network

Info

Publication number: MXPA00012099A
Application number: MXPA/A/2000/012099A
Authority: MX
Inventors: David P Frankel; Joe Boucher; Kenneth M Kolderup
Original assignee: Jetstream Communications Inc
Priority date: 1998-06-08
Filing date: 2000-12-06
Publication date: 2002-07-25

Abstract

A system and method of communicating voice and data via a local packet network (LPN) to and from a customer site. A remote digital terminal (RDT) is provided at a customer site to interface a plurality of telephone devices and/or data devices (computers or a local area network of computers) with the LPN via a local loop link, such as a Digital Subscriber Line or a wireless local loop. A host digital terminal (HDT) is provided at a control site within or connected to the LPN that coordinates the communication of voice calls between the RDT and a public switched telephone network (PSTN) switch via the LPN and that coordinates the communication of data between the RDT and a data network within or without the LPN. Multiple telephone calls with the customer site can be supported by the remote digital terminal over a single local loop link connected to the LPN. In addition, the HDT can support communication with multiple RDTs. In order to provide POTS service to customer sites, a wire center remote digital terminal is provided.

Description

SYSTEM AND METHOD FOR VOICE AND DATA COMMUNICATION IN A LOCAL PACKET NETWORK FIELD OF THE INVENTION The present invention is directed to a system and method for providing voice and data services over an access network that supports a transport protocol based on a digital packet, such as Digital Subscriber line technology (DSL). ). In addition, the present invention is directed to a system and method for providing a conventional analog telephony service to supplement the service provided through a transport network based on digital packet.

BACKGROUND OF THE INVENTION The Telecommunications Act of 1996 officially opened the telecommunications market in the United States for competition. Prior to 1996, the Bell Operating Regional Companies (RBOCs) maintained monopolies over the service of local telephony within their regions. As a result of the document, the RBOCs were designated as Incumbent Local Exchange Carriers (ILECs) and companies that competed with the ILECs were referred to as Competitive Local Exhange Carriers (CLECs). To date, states have registered hundreds of new companies established as CLECs and some are Now offering a competitive local service. CLECs offer local services that can be selected from two basic network strategies to provide the service. A CLEC can buy its own switching and transmission equipment and build a local telecommunications network together with an ILEC network. The CLECs that follow this strategy are referred to as CLECs based on facilities. Alternatively, the Telecommunications Act of 1996 makes provisions for the CLECs to re-label and resell the ILEC services purchased at a discount. The CLECs that follow this strategy are referred to as resale CLECs. In some cases, a CLEC will buy both strategies. Although many CLECs initially acquired a resale network model, most are now focused exclusively on providing a local service based on facilities. The resale model had initial appeal because it allowed a CLEC to rapidly offer a wide range of services for commercial customers and consumers in many geographic markets with little initial capital investment. However, the profit margins from resale were inadequate as a viable long-term business strategy. There are two main components for a local telecommunications network, the switching network (or core) and the access network. As a further simplification, the switching network provides the service as long as the access network transports the service to the client. For an ILEC, the multi-million dollar digital switches located in each community in a geographic market constitute the switching network, while the thousands of pairs of copper wires that move from each central office (CO) to the facilities of the client constitute the access network. However, CLECs demand local networks that are very different from those used by ILECs. CLECs do not need, nor could they manage to immediately build decentralized switching networks to service each potential subscriber in a market. Therefore, the CLEiCs select to centralize their switching systems, using one or two switches to service an entire market. However, while a centralized switching strategy is more efficient and less expensive, it presents a challenge to design an access network capable of serving a geographically dispersed and small customer base. An access network must accommodate the increased distance between the switching equipment and each consumer site. As a challenge is added, most CLECs intend to offer data service and local telephony services, such as fast high-speed Internet access. Consequently, CLECs need to access networks that are capable of providing voice and data services to avoid the complexity and cost of building separate access networks for voice and data. To meet these challenges, most CLECs are switching to broadband access networks: access networks that allow a high bandwidth connection to be established between the centralized installation of CLECs and remote client sites. The transmission equipment is now available, which can allow a CLEC to provide voice and data services on several of the new broadband access networks. Broadband access networks generally consist of two components. The first is called the structure network that connects the centralized switching equipment of a CLEC to a centralized location within each community, such as the ILEC central office. The structure portion of a CLEC broadband access network is usually an optical fiber network, such as one that adheres to the Synchronous Optical Network (SONET) standard. The second component is called the "last mile" network and is the connection from the location of the community to each client site. There is a variety of broadband technologies available for the last mile portion, and one selected for the use of CLEC that can greatly affect the capital investment required to serve a community. The latest mile broadband access technologies currently available for use in access networks by CLECs are Fiber to Building (FTTB), Hybrid / Coaxial Fiber (HFC), Wireless Local Cycle (WLL) and Digital Subscriber Line (DSL). ). Traditionally, telephone subscribers have been connected to the Public Switched Telephone Network (PSTN) through a last mile network that physically consists of a pair of copper wires that travel through a subscriber (private or office) and the "wiring center" of the telephone company. The cabling center typically serves thousands or even tens of thousands of subscribers in a neighborhood or community and hosts a "central office switch" that ends with each pair of subscriber cabling. The switch controls the telephone at each subscriber installation, providing power, sound and audio signals in analog form on the cable pair. The switch also detects when a subscriber line goes "off-hook", dials numbers, etc., and in response routes and connects the calls to other subscribers or to the other switches in the PSTN. In this summary it is known that the "Old Normal Telephone Service" (POTS) and is an analog technology (as opposed to digital technology). Subscribers who require more than one individual telephone "line" can be served by installing the corresponding number of POTS circuits using multiple copper wires. Alternatively, a "torque gain" system can be deployed, which multiplexes the signals for the telephone lines on a single pair of wires. This is achieved with special equipment at each end of the copper pair. The torque gain equipment converts an analog POST signal into a digital format, usually at 64 kilobits per second. A digital connection is established on the copper pair, with enough bandwidth to carry all the required bit streams. Time division multiplexing is used to combine the bitstreams. A typical part gain arrangement is a "T-1" line that operates at 1,536 megabits per second (Mbps) allowing the transport of 24 individual channels or streams to 64 kilobit / second. At a subscriber location, the special equipment converts each of the 24 currents to and from a conventional POTS signal format. In the wiring center, similar equipment is required. The T-1 technology is not always the most economical using the existing infrastructure of the POTS system since the T-1 service requires the deployment of a significant amount of special equipment and infrastructure. In addition, if a subscriber requires less than 24 service lines, the T-1 solution is even less attractive because the cost of equipment is distributed over fewer lines. In the central office switch, a T-1 line is terminated by the special port that is dedicated to that subscriber, even if only a fraction of the 24 channels are used by the subscriber.

DSL is a high-bandwidth technology that allows data to be transferred to and from individual subscriber locations at various speeds, which currently vary up to 2 Mbps. Data is transferred over a DSL access portion of a packet network Local (LPN) as "packets", and packets move over the LPN only when the information is moving to or from the subscriber and the line is in an otherwise unoccupied condition. An LPN is a network that provides data connections between subscribers in a local service area with various connection types and data rates. Typically, an LPN consists of a plurality of DSL multiplexers and data switches. The DSL equipment is designed to service a large number of subscribers, resulting in relatively low costs per subscriber. DSL technology is established as the most attractive for a CLEC in terms of capital investment. The broadband access technologies FTTB, HFC and WLL each require the installation of significant infrastructure (fiber optic cables, coaxial cables, base stations and repeaters, etc.), which is not economical for a CLEC that is going to service a decentralized small base or medium-sized business customers. DSL operates on the existing last mile copper networks (local cycles) of the ILECs and therefore does not require significant capital expenditures for deployment. Instead, the CLEC pays a monthly fee to the ILEC for each of the local cycles it uses. In addition, DSL has the right capacity to service residential markets up to medium-sized businesses. In general, the DDSSLL access portion of a local packet does not carry the voice and is not connected to the central office switch. However, some DSL implementations can be combined, over a pair of digital signal transports, as a single POTS signal that carries analog voice. This allows a DSL subscriber to use the line for a telephone call while simultaneously transferring packet data. However, this approach is limited to a single POTS signal and requires POTS compatible equipment to terminate the line in the wiring center, in addition to packet-oriented DSL equipment. It is desirable to provide a system that allows the total service-based CLECs to transport the local telephony service, including multiple voice call services and ddaattooss services aa cclliieenntteess ccoommeerrcciiaeess of small and medium size over an access network that supports a pprrooffooccoolloo of ttrraannssppoorrttee eenn bbaassee aa ppaaqqui ete digital, preferably on lines of pairs of existing copper cable. It is also desirable that the system uses the least number of local cycles and that a minimum amount of CLEC equipment is required at the ILEC cabling center.

PREVIOUS ART In summary, the present invention is directed to a system and method for using a local packet network (LPN) that supports a transport architecture based on a digital packet such as a Digital Subscriber Line (DSL) to provide Internet services. voice and optionally data about an individual local cycle, such as a DSL, towards a client installation. Multiple voice telephone calls as well as data services for a client installation are supported on a se DSL connected to that client installation. In a customer facility, a plurality of telephone devices (such as telephones, facsimile machines, modular and / or office telephone system ports) and data devices (such as those connected through a local area network) are interconnected with a local cycle link connected to the LPN. Analog telephone signals (representvoice, facsimile signals or modulator signals) received from a plurality of telephone devices are converted to digital voice band packets. Control signals representoff-hook signals, dial tone, call set-up information and other call control signals are converted to digital call control packets. The voice band packets, the call control packets and the data packets (from the data devices in the client installation) are modulated for transmission by means of the local cycle link on the LPN. In the reverse direction, the modulated speech band packets, data packets and call control packets received from the LPN intended for client installation by means of the LPN on the local cycle link are demodulated. The demodulated voiceband packets are converted to analog telephone signals for connection to the appropriate telephone devices at the customer's facility. The demodulated data packets are coupled to the data devices (in the local area network) in the client installation. The demodulated call control packets are processed to control call set-up and maintenance functions at the customer site. At the control site within or connected to the LPN (such as the central switchfacility), the voiceband packets, call control packets and data packets from the client installation are received by means of the LPN. The voice band packets received from the client installation by means of the LPN are converted to time division multiplexed signals and are coupled to a public switched telephone network (PSTN) switch in allocated time segments. The data packets received from the client installation are coupled to a data switch for transfer to a data network (such as the Internet). The call control packets are processed to control call set-up and maintenance functions in the control installation. In the reverse direction, the data packets destined to the client installation are received from the data switch and coupled to the LPN for transmission to the client installation. The timeslot division multiplexed voice signals received from the PSTN switch intended for client installation are converted to voiceband packets and are coupled to the LPN for transmission to the customer facility. Accordto the present invention, a specialized device that is called a remote digital terminal (RDT) is provided in the customer's installation and in another specialized device, called a digital guest terminal (HDT) is installed in the central switch facility. Alternatively, the specialized functions of the HDT are integrated in a data switch in the LPN or in a PSTN switch. Similarly, RDT functions can be integrated into a key branch / private branch exchange device system or other equipment in the customer's installation. The RDT and HDT transport digitized voice band packets and data packets to each other through the LPN. The RDT converts the appropriate voiceband packets for communication over the LPN to and from analog telephone signals suitable for use by the connected telephone devices. In a similar way, the HDT converts the voice band packets to and from a time division division multiplexed format suitable for communication by means of the PSTN switch. According to another aspect of the invention, an apparatus called remote digital terminal of wiring central (WC-RDT) is provided in a cabling center to interconnect with a plurality of local cycle links with a subscriber line access multiplexer. digital (DSLAM) in order to provide the POTS service over local loop links to client facilities. The WC-RDT is used to provide the POTS service to client facilities that have a RDT as well as client facilities that do not have a RDT. The foregoing and other objects and advantages of the present invention will become readily apparent when reference is made to the following description, taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is a block diagram of a telecommunications system employing the remote digital terminal and the host digital terminal of the system and the method according to the present invention. A-Central switching facility; B- PSTN switch; C-Data switch; D-Data Network (INTERNET). FIGURE 2 is a block diagram according to a remote digital terminal according to the present invention. A-DSL modulator; B-Controller; C-Ethernet. FIGURE 3 is a block diagram of a host digital terminal according to the present invention. A-Storage disk; B-Screen; C-Memory; D-Microprocessor / Controller; E-Package Conversion Processor; F-IF Data Switch; G-Towards Data Switcher; H-Toward LPN; l-Toward PSTN switch. FIGURE 4 is a flow chart illustrating a call setup procedure in the remote digital terminal. A- Detect off-hook of a telephone device; B-Send message to guest digital terminal by means of LPN indicating off-hook status; C-Receive call reference value to be associated with the call from the guest digital terminal; D-Receive the voice-band dial tone data from the guest digital terminal. FIGURE 5 is a flow chart illustrating a call set-up procedure in the guest digital terminal. A-Receive notification from the remote digital terminal that a telephone has been off-hook; B- Identify the source of the request and validate it; C-Notify the PSTN switch of the request; D-Receive the assigned time segment from the PSTN switch and the dial tone over that time segment; E-Assign the call reference value for the call and notify the remote digital terminal accordingly; F-send voice-band dial-tone data to the remote digital terminal. FIGURE 6 is a flow diagram illustrating a procedure of the voiceband data in the remote digital terminal. A-Telephone device; B-Analogue < Digtal; C- Bit streams < ?Packages; D-Transmission / Reception through LPN. FIGURE 7 is a flow diagram illustrating a procedure of the voice band data in the guest digital terminal. A-Transmission / Reception through LPN; B-Packages < • TDM signals; C-To / from PSTN switch. FIGURE 8 is a block diagram showing an improvement to the system where a remote digital wiring center terminal is provided in a wiring center to provide standard analog service to customer premises without a remote digital terminal, or for clients equipped with a remote digital terminal, even if your remote digital terminal is not in operation. A-Central switching facility; B-PSTN Switch; C-Data switch; D-Data Network (Internet); E-Separator / Combiner; F-Wiring Center; G-Modulator FIGURE 9 is a block diagram of the remote digital terminal of the wiring center. A-Protection Circuit; B- Towards the local cycle link; C-Controller; D-Modulator; E- Towards DSLAM.

DETAILED DESCRIPTION OF THE INVENTION 5 FIGURE 1 is a general diagram of a system 5 that allows a full-service CLEC based on facilities for transporting local telephone services and data services to small and medium-sized businesses. The present invention is described to be useful in the use of a particular type of local cycle link, called DSL network. However, it should be understood that the teachings described herein are applicable to any access network that supports a transport protocol based on digital packet. DSL is just one example of such access network technology protocol. The main components of the system according to the present invention are a remote digital terminal (RDT) 100 and a digital guest terminal (HDT) 200. The RDT 100 resides in a customer facility (subscriber) shown in the number of reference 7 and interconnects with a plurality of telephone devices (TDs) 10 and, optionally, a local area network (LAN) 12 to a local cycle link, such as a line that supports the Subscriber Line transport protocol Digital (DSL). For simplicity, the local cycle link is referred to as DSL 24.

Other local cycle links that may be suitable for use together with the present invention are wireless local cycles, such as digital cellular local cycles and the like. The DSL 24 is an access network of a local packet network (LPN) 60. The LPN 60 comprises one or more data switches 62, such as the Asynchronous Transfer Mode (ATM) switches and one or more access multiplexers. DSL (DSLAMs) 64. The data switches 62 consist of one or more processors controlled by the software. The data controllers 62 are connected to each other and to DSLAM 64 preferably via optical links, such as synchronous optical network facilities (SONET) 66. In each ILEC (CO) central office, there is a DSLAM 64 which controls the distribution ( and collection) of signals to and from a plurality of DSLs 24. The combination of DSLAM 64 and data switches 62 make up LPN 60. LPN 60 provides data connections between subscribers in a local service area with various types connection and data speeds. For example, the LPN should include DSL connections at speeds ranging from 256 Kbps to 6 Mbps used by households and small businesses, T3 connections at 45 Mbps used by large businesses and small Internet Service Providers (ISPs) and OC-3 connections for use by large companies and ISPs. Returning to the description of a client installation 7, the TDs 10 can be connected directly to the RDT 100 or to a key branch system / private branch exchange (KTS / PBX) 14 device that is connected to the RDT 100. The connections between the RDT 100 and the associated TDs are through standard analog telephone lines 25, or alternatively through other standard telephony interfaces such as T-1, ISDN, etc. The connections between RDT 100 and KTS / PBX 14 are by means of a plurality of branches 27. The function of the RDT 100 is to allow the voice traffic associated with one or more TDs 10 and the data traffic from LAN 12, if there would be, to be converted to and from a format that can transit in the LPN 60. It should be understood that the voice band traffic associated with the TDs 10 can be voice, digital data modulated from a modulator, facsimile machine and possibly certain call control signals (such as ring tone, busy signal, etc.). The data traffic is that traffic associated with LAN 12 or other devices based on data packets in the client installation 7. As is well known in the art, DSL is a communication technology that allows data to be transferred from individual subscriber locations at various speeds, currently as high as 2 Mbps using the existing braided cable line infrastructure already in place in most of the industrialized parts of the United States and the world. That is, DSL 24 is a standard twisted pair cable line that is used to transmit information that is formatted according to the DSL transport protocol. The HDT 200 resides in a control site within or without the LPN 60. For example, FIGURE 1 shows the HDT residing in a CLEC switch facility 30 and interconnecting with a PSTN switch 32 and a data switch 34 for the fiber structure of the LPN 60. The PSTN switch 32 can route voice calls to the local PSTN 42 or to a long distance network. The data switch 34 can route the data packets to and from a data network 50, such as the Internet. The HDT links 200 by means of an optical fiber 26 or another installation connected to the LPN 60. The CLEC switching device 30 will also be referred to hereinafter as a central switching facility. The data switch 34 in the central switching facility 30 and the data network 50 can route the data directly to the LPN 60, bypassing the HDT 200. Similarly, a data switch 62 on the LPN 60 can directly route the data to the data network 50. Alternatively, the functions of the HDT 200 can be incorporated in a control facility at another location in the system. For example, the functions of the HDT can be incorporated in a data switch 62 of the LPN 60 instead of being executed by a separate unit. The software carrying the functions of the HDT 200 (described below) can be provided in the data switch 62 to be executed by the processor or processors in the data switch 62. The software in the data switch 62 can be improved to execute the functions of the HDT 200 and interconnect directly to the PSTN switch 32, the data switch 34 or the data network 50. Similarly, the software may be provided in a PSTN data switch 32 to be executed by the processors associated with the PSTN switch 32. Returning to FIGURE 2, with continuous reference to FIGURE 1, the components of RDT 100 will be described. In a preferred embodiment, the RDT 100 is presented as a circuit board housed in a suitable enclosure with a source of energy. Specifically, according to a preferred embodiment, the RDT 100 comprises a controller 110, a DSL modulator 120, a static random access memory (SRAM) 130 for temporarily storing the working data, a read-only memory (ROM) 140 which stores a software program for the controller 110, a plurality of subscriber line interface circuits (SLICs) 150, a plurality of encoders / decoders (CODECs) 160 and an Ethernet 170 interface. The DSL 120 modulator directly connects to the DSL 24. The DLS modulator performs the modulation and demodulation necessary to carry the information by means of the DSL 24 within the LPN 60. There are several modulation / demodulation formats that are known in the art for use over a DSL 24. The modulator DSL 120 also formats the modulated information into a suitable packet format, such as the asynchronous transfer mode (ATM) protocol for example, which is used by the equipment in the LPN 60 for the transport of information. Alternatively, if the local loop were a wireless local loop link, the modulator 120 would be a wireless modulator capable of performing the modulation and demodulation necessary to carry the information via a wireless link. In addition, a transceiver (not shown) would be connected to the modulator 120 to transmit wirelessly and receive the modulated information. The controller 110 is connected to the modular DSL 120, the SRAM 130, ROM 140, the Ethernet interface 170 and a timeshare division multiplexer (TMD) busbar 180. In addition, the controller is connected to each of the SLICs 150 by a control bus 155 to allow the controller 110 to detect when a TD 10 is off-hook and to instruct a SLIC 150 to sound a TD 10. Each SLIC 150 is connected to a TD 10 or a PBX / KTS 14 through a standard analog telephone line. The SLIC 150 provides the precise voltages and currents required to connect with telephone devices, such as standard telephone sets, facsimile machines, etc. The CODEC 160 is an encoder / decoder that converts the analog telephone signals (voice and other telephone signals in band) to digital bit streams, and converts the digital bit streams to analog telephone signals. The controller 110 is connected to each of the CODEC 160 by the busbar TDM 180. The number of TDs 10 served by RDT 100 will determine the number of SLICs 150 and CODECs 160 required. However, as will be explained later, the number of telephone devices that may be in use at any time depends on the bandwidth of the local cycle link. The Ethernet interface 170 is a standard network interface circuit that interconnects with the digital data between PCs or LANs 12 connected. The controller 110 is preferably a microprocessor that operates in accordance with the software stored in ROM 140. The operation of the controller 110 can be updated or modified using a non-volatile reprogrammable ROM memory., such as an "instant" memory, which is well known in the art. The controller 110 under the control of the software program stored in the ROM 140 executes two main functions: control of the call setup and data and voice / band conversion. As an alternative to the implementation shown in FIGURE 2, the RDT 100 can be implemented using a PC with connection cards that provide the necessary interfaces (DSL, telephone and Ethernet). Even another alternative is to provide a server computer that provides call control functionality for a plurality of multimedia client PCs each having connectable telephone and sound cards so that each PC can support a telephone call. Even another alternative is to implement the functions of the controller 110 by means of a digital signal processor (DSP) or an application-specific integrated circuit (ASIC). In addition, instead of providing a plurality of individual SLICs 150, a single subscriber line interconnection capable of coupling a plurality of signals to and from a plurality of telephone devices can be used. Similarly, an individual voice conversion device having the processing capability to execute multiple conversions may be used in place of the plurality of separate CODECs 160. The function of RDT 100 is to allow traffic associated with one or more telephone calls that are to be converted to and from a form that LPN 60 can transit. More specifically, RDT 100 functions include interconnecting with a local cycle link such as DSL (by means of an integrated or external DSL modulator); that converts voice / band packets to and from conventional analog telephone signals; convert data packets to and from a format suitable for transport through the LPN; process the call control functions (ringing, on-hooking and off-hook) to generate and detect the call performance packets sent and received by the LPN; provide an electrical interface for conventional telephone equipment; manage the distribution / allocation of the bandwidth over the local cycle link with other functions (not telephone); and provide remote administration and maintenance functions. Returning to FIGURE 3, together with FIGURE 1, the HDT 200 will be described. The HDT 200 performs complementary functions to those executed by RDT 100. A single HDT 200 can support communication with a plurality of RDTs 100 that are connected to the LPN 60. In the preferred embodiment, the HDT 200 is implemented in a computer system conventional, with specialized software that controls a set of electronic interface components. Specifically, the HDT 200 shown in FIGURE 3 comprises a microprocessor-based controller 210, a busbar, the Peripheral Connection Interface (PCI) 220 busbar, a storage disk 230, a display 240, and a memory 250, such as SRAM. The HDT 200 interconnects with the PSTN switch 32 via a PSTN (IF) interface, such as T-1 IFs 260, which preferably communicates via the Bellcore GR-303 signaling interface. That is, the T-1 IFs 260 connected to the T-1 lines, which are in turn connected to the PSTN switch 32. The HDT 200 interconnects with an optical link connected to the LPN 60 by means of an LPN IF 270 device, such as an OC-3 optical link that uses the Asynchronous Transfer Mode (ATM). Similarly, a data switching IF device 290 is provided to interconnect with the data switch 34. The PC cards implementing the functions of the LPN IF 270 device and the IF 290 data switch are connected within the PCI bus 220. The LPN IF 270 device connects to the LPN 60 by means of an optical fiber (FIGURE 1) and provides a data transfer rate of 155 Mbps in each direction. The ATM cells are sent and received over the link, where each cell contains address information, which includes source and destination information, as well as the data to be transferred. Alternatively, the LPN IF 270 device operates at other speeds, such as OC-12 at 622 Mbps, Fast Ethernet (100 Mbps) or Gigabit Ethernet (1000 Mbps). However, the preferred modality is the ATM-155 standard. The T-1 IFs 260 are coupled to a packet conversion processor 280 via a TDM busbar 285. Similarly, the data switch IF 290 and LPN IF 270 are coupled to the packet conversion processor 280 via a busbar TDM 287. The function of the packet conversion processor 280 is to convert the information between different data formats used by the devices connected thereto. For example, the packet conversion processor 280 converts the packets received from the LPN via LPN IF 270 to a time-division multiplexed format for coupling to T-1 IFs 260. Similarly, the conversion processor of packet 280 converts received packets from LPN IF 270 to a suitable format for coupling to data switch IF 290. The packet conversion processor 280 executes those conversions in reverse manner as is appropriate. The packet conversion processor 280 is preferably implemented by an application-specific processor and its operation is monitored by the microprocessor / controller 210 for call control, call setup, system errors and other issues. In some configurations, the function of the packet conversion processor 280 may be included within the functionality of the microprocessor 210. The T-1 facilities connected to the PSTN switch 32 are logically divided into "time slices" using timeshare division multiplexing. . Each T-1 line carries 24 time segments or channels, with each channel carrying a single digitized voice conversion. One or more of the 24 channels are designated to a control and transport channel in the signaling information between HDT 200 and the connected PSTN 32 switch. The use of the control channel is described in more detail below.

Preferably, the HDT 200 is designed to have a modular architecture that is easily scalable. The HDT 200 can support as cost-effective as many as 100 end-user lines and 24 branches for voice switch 32, and as many as 6,000 lines and 2,000 branches. Additional HDTs can be added to handle as many as 100,000 lines or more. The HDT 200 is preferably designed to provide "conveyor class" availability, including redundant and "immediate exchange" components. A level 3 NEBS compatible platform-mounted system designed to reside in a central office environment is preferable and can be designed to have an N + 1 redundancy. A software program stored in the memory 250 allows the microprocessor 210 to execute the control functions analogous to call establishment and functions executed by RDT 100 and support communication with multiple RDTs 100 simultaneously. As mentioned before, the software for carrying out the HDT 200 functions can be incorporated directly into the PSTN switch 32 or the data switch 62 so that a separate "box" performs the functions of the HDT 200 that would not be necessary. The operations of RDT 100 and HDT 200 are described with reference to FIGS. 4-7, together with FIGURES 1-3. In order to transport the voice and data services through the DSL access portion through the LPN 60, the RDT 100 and HDT 200 employ a compatible digital signaling and information transfer protocol. There are many protocols well known in the telecommunications art, and it is likely that many new protocols will be created to be useful in connection with the system and method of the present invention. The ATM protocol is the example of an adequate protocol. The ATM protocol is a format that divides a bandwidth into a plurality of cells each of which may contain voice / band packets, data packets, call control packets, etc. The local loop link supports in each direction the transport of voice / band packets representing analog voice-band telephone signals, data packets associated with data services (computers on a LAN) and call control packets. A voice-band packet includes an identifier (source and destination) and voice-band packet information. A call control packet includes a control signal (which is identified as a control message), a control message (off-hook, busy, etc.) and an identifier associated with the call to which the control message is applied . If your use the ATM protocol, each packet occupies an ATM cell. Upon receipt of a packet, the first RDT 100 and HDT 200 detects the type of packet received (by a control signal or other identification information) in order to determine whether the packet represents the functions of call control, voice information -band or data information. The RDT 100 converts the analog telephone signals to and from an appropriate digital packet format in order to communicate with the attached analog TDs. In addition, if communication with the data devices in the client installation is supported and required, the RDT 100 converts the data packets of the data devices to and from a suitable packet format for communication by means of the LPN. Similarly, the HDT 200 converts the information packets-band and the data packets between different types of digital formats in order to conduct the communications by means of the PSTN switch 32 and the data switch 34. Returning to FIGURE 4, with reference to FIGURE 2, a call set-up procedure 300 in the RDT 100 is described. The procedure occurs when a call is initiated by one of the TDs 10 connected to RDT 100. In step 310, a SLIC 150 detects that a connected TD 10 is off-hook and a corresponding signal is coupled to the controller 110. The controller 110, in step 315, generates a control message (formatted within a call control packet) indicating the off-hook state and requesting a dial tone, which is transmitted to HDT 200 by means of LPN 60. Controller 110, in doing so, first determines if there is available bandwidth on DSL 24 based on the number of other voice calls that are currently maintained by RDT 100. If there is bandwidth available, then the message is sent to HDT 200; otherwise, a "busy" or other signal indicating unavailability is sent to that telephone device. Next, in step 320, the RDT 100 receives a call control packet from HDT 200 that includes a call reference value to be associated with that call. In step 325, a call control package or voice-band packet (depending on the implementation of the system) representing a voice-band-marking tone is received from HDT 200 which is converted to a current of digital bit by means of RDT 100 converted to an analog dial tone signal by CODEC 160 connected to TD 10 by SLIC 150. FIGURE 5 illustrates the procedure of setting complementary call 400 on the HDT 200, again, in the case when a call it is initiated by a telephone device connected to the RDT 100. The use of the ATM protocol is referred to in the following description as an example of a suitable network technology used by the LPN. Reference is also made to FIGURE 3 in relation to this description. In step 410, the HDT 200 receives a call control packet containing a control message from RDT 100 indicating that a telephone device has been off-hooked. In step 415, the HDT 200 identifies the source of the call control message by searching at the address provided in the ATM cell containing the call control packet request. This is verified if the answer is valid or not, that is, it comes from a client installation 7 whose account is active. In step 420, the HDT 200 notifies the PSTN switch 32 via the designated channel on one of the T1-IFs 260 of the request. In response, the PSTN switch 32 allocates an available time slot for the call in one of the T-1 facilities, and this time segment information is received by the HDT 200 in the time step 425, together with a dial tone in that segment of time. Next, in step 430, the HDT 200 allocates a call reference value for the call and communicates that value in a control message that is transmitted to RDT 100. Finally, in step 435, the HDT 200 generates packets of voice-band representing a dial tone for the call and transmitting it to RDT 100. Calls that are initiated by devices on the HDT side to the system are received by HDT 200 when the PSTN 32 switch detects a coupling between a telephone number received and a table of telephone numbers assigned to a client installation within the supervising control of HDT 200. In response, the HDT 200 transmits to the RDT 100 a call control packet containing a command for a ring signal that is interpreted by RDT 100 to generate an analog ring signal for connection to appropriate TD 10.

A call reference value is assigned, and the voice-band packets are exchanged between HDT 200 and RDT 100 in a manner analogous to that described for a call initiated in RDT 100. When the telephony device addressed in RDT 100 is off-hook , the RDT 100 generates a control packet indicating the same, and the HDT 200, upon reception of the packet, notifies the PSTN 32 switch that the call has been answered. Subsequently, the operation of RDT 100 and HDT 200 continues as explained below. The communication of a data packet to a data device in a client installation is initiated in an analogous manner when the data switch 34 receives a data packet destined for a data device in the client installation. It should be understood that the "telephone numbers" associated with TDs 10 connected to RDT 100 are handled by the PSTN switch 32 located in the central switching facility 30. When a person anywhere in the PSTN 42 dials a number, such as 404- 555-1234, traditional PSTN technology routes that call to the PSTN switch 32, which in turn displays the call information, as described herein, to the HDT 200 for transmission to RDT 100 and finally to the connected TD 10. Therefore, the TDs 10 connected to RDT 100 operate identically to the telephone devices directly connected to the central switching facility 30 and can make and receive PSTN telephone calls in the traditional manner. Once a call between RDT 100 and HDT 200 is established, the remaining communication will mainly consist of voice-band packets, or data packets depending on the end devices that communicate with each other until the call is terminated. In general, only when new calls are initiated, calls are terminated, or system errors are presented which will call the control packets that are presented over the local cycle link. The operation of RDT 100 once a call is established is described with reference to FIGURE 6, together with FIGURES 1 and 2. There are two main conversion processes that are presented in RDT 100: the conversion from analog to digital and the from digital to analog shown in step 510, and the digital bit stream to packet and packet to bit stream in step 520. The analog to digital conversion (and vice versa) is executed by CODECs 160 for analog telephone signals . Some call control related to the telephone signals is generated by the controller 110 by means of SLICs 150. The bit stream to packets (and vice versa) is executed by the controller 110. To explain it further, the signal flow from TD 10 to LPN 60 is described first. The analog telephone signals from an attached TD 10 are received and digitized by the aggregate CODEC 160, creating a digital bit stream representing the real-time analog telephone signals generated by TD 10. The digital bitstream is placed on the busbar TDM 180. In step 520, the digital bitstream is converted into digital packets called voice-band packets. Each voice-band packet contains a plurality of voice-band information bytes, each representing a sample of the voice (or analog telephone signals) at a predetermined interval, such as 125 microseconds. An individual voice-band packet contains a predetermined number of speech information samples, such as 40, representing 5 msec of speech, for example. More specifically, the controller 110 accepts 1 byte of digital data from the TDM 180 busbar every 125 microseconds, and temporarily stores the information in SRAM 130. When a complete voice packet is accumulated in SRAM 130, the controller 110 formats the packet with its call reference value and transfers them to the DSL 120 modulator, causing it to be modulated and transmitted by the LPN 60 to HDT 200. The controller 110 under the control of the software stored in ROM 140 performs this process for all calls that are active in RDT 100. Similarly, when the controller 110 receives the data packets via the Ethernet 170 interface from LAN 12, stores it temporarily in SRAM 130 for modulation of the DSL 120 modulator and transmission by means of LPN 60. Depending on the availability of the DSL bandwidth 24, the controller 110 may temporarily store the digital data of LAN 12 until there is sufficient bandwidth available, giving priority to the voice-band information. The controller 110 carries out this process for each of the TDs 10 that are active at any given time, sequencing through each CODEC 160, accumulating a voice-band information for each call, and passing it to the DSL 120 modulator for transmission when it is saturated The construction of the packets is linked by the controller 110 so that all the packets are not ready for simultaneous transmission, instead, a packet for a first call is completed and then the packet for the next call is completed at a fraction second after, allowing the packet for the first call to be transmitted by the DSL modulator 120 so that it is ready to accept the packet for the next call when it is ready. Alternatively, the voice-band data for several calls can be multiplexed together into a single voice-band packet containing identifiers for each call and data of each call. This alternative technique reduces any potential delay that may occur as a result of the packet formation process. In the reverse direction, the DSL 120 modulator receives modulated voice-band packets and data transmitted over DSL ^ Ü ^ ¡^ ^ 24 from the central switching facility 30. The DSL modulator 120 demodulates the modulated voice-band packets and the modulated data packets and couples them to the controller 110. The controller 110 receives the voice-band packets demodulated and the data packets and identifies the voice-band packets by the call reference value contained therein. The controller 110 stages the voice-band packets in SRAM 130, forming queues of subsequent voice-band packets as received. Simultaneously, the controller 110 takes the individual bytes of the data from SRAM 130 and places them on the TDM 180 bus at the rate of 1 byte every 125 microseconds for connection to one of the appropriate CODECs 160, associated with the TD 10. addressed. The CODEC 160 converts the data from the digital bit stream to analog telephone signals that are coupled by the SLIC 150 for the TD 10. With respect to the received data packets, when the controller 110 detects the reception from the DSL modulator 120 of A data packet not associated with telephony functions directs it to the Ethernet interface 170 where it is coupled (according to an associated address) to the appropriate data device on LAN 12. The RDT 100 establishes the priority for the use of the bandwidth of the local cycle link between voice traffic and data traffic. For example, the controller 110 may be programmed to assign the use priority to the local cycle link for voice traffic over data traffic. In this case, the bandwidth over the DSL connection will be used for voice calls when they are active, although they will be available for data traffic when any of the TDs 10 is idle. Typically, the bandwidth of a DSL is as high as 2 Mbps. The controller 110 may designate a portion of that bandwidth for voice traffic, during all or only the adjustable periods during a day. Once the maximum data traffic is reached, no additional data traffic would be allowed. These traffic parameters are programmable in a RDT 100, and if necessary, can be adjusted in real time to accommodate sudden bandwidth allocation needs. With reference to FIGURE 7, together with FIGURES 1 and 3, the operation of the HDT 200 in the processing in call process is described. The voice-band packets and data packets sent by RDT 100 through LPN 60 are received by LPN IF 270. The packet conversion processor 280 converts the voice-band packets into multiplexed signals by timeshare division (TDM) in a process similar to that in RDT 100, and couples the TDM signals by means of a T-1 IF 260 to the PSTN switch 32 in an assigned time slot. The data packets received from RDT 100 are (reformatted if required by the packet conversion processor 280 and) coupled to the data switch 34 by the data switch IF 290 under the control of the microprocessor 210. In the reverse direction, the HDT 200 receives the TDM signals of a given call from a T-1 IF 260 at a rate of one byte every 125 microseconds. In a process similar to that in RDT 100, the packet conversion processor 280 temporarily stores the data bytes of the TDM signals in the memory 250 to form voice-band packets that are dispatched to RDT 100 by means of the LPN IF device. 270. The data packets received from the data switch 34 are coupled to the LPN IF 270 device for transmission to the client site. The HDT 200 can be involved in bandwidth usage control. For example, the microprocessor 210 may be programmed to continuously monitor the amount of bandwidth of the local loop link located in a given RDT 100 in a client facility for voice traffic to determine the availability of the remaining bandwidth in the link of the local cycle for data traffic. The microprocessor 210 can be programmed to limit the data traffic to the client installation from the LPN so that a predetermined portion of the total bandwidth available for client installation on the local cycle link used by RDT 100 remains available for voice traffic. further, the microprocessor 210 can be programmed to generate a message that is sent to a data switch 62 in the LPN 60 indicating that the amount of bandwidth available for the data so that the data switches 62 in the LPN 60 can be required by this rule in the transmission (or non-transmission) of data traffic to HDT 200 intended for a particular RDT 100 in a particular client installation. In order to be competitive in the local market, CLECs must provide service that is of the same quality that the customer is currently receiving from ILEC. To achieve this, the system of the present invention digitizes voice conversations using standard "μ-law" coding (64 Kbps) and does not need to use voice compression (although compression can be used if desired to reduce the use bandwidth through the LPN). In addition, to avoid the delays (waiting time) inherent in some packet networks, the system according to the preferred mode uses ATM signaling and is optimized throughout the system to limit the temporary memory sizes and queues, ensuring that the voice-band data moves quickly between the RDT and HDT. Returning to FIGURES 8 and 9, an improvement of the system 5 will be described. The conventional telephone service (POTS) is provided on an "analogous cycle" that transports audio and signaling communications between a customer's telephone device and the customer's wiring center. the telephone company (WC). A fundamental attraction of this technology is the connection capacity that is provided by the WC, and therefore, with adequate backup power systems in that location, the telephony service remains available even when the power is interrupted on the site. of client. Additionally, only a simple and generally very reliable telephone set is required at the customer's location, resulting in a service that is subject to minimal disruption. Increasingly, telephone companies have used more sophisticated digital technology to provide telephone service; This approach requires more complex equipment at the subscriber's location and the equipment is inherently subject to additional failure modes and requires local power. Typically, this equipment is installed in locations of larger businesses where it may be practical to also install backup power equipment and redundant electronic components, so that at least some telephone service can be maintained even when equipment or conventional power fails. 20 The telecommunications industry is eager to bring the advantages of digital technology to residential subscribers, preferably providing the reliability associated with conventional analog telephone service. That is, generally, the lack of cost effectiveness for the equipment of the ^^ ggjj? ^ g g ^ residential subscriber with backup power equipment and redundant electronic components. DSL technology is a very effective mechanism against the cost to provide high bandwidth digital data for a residential subscriber. As noted above, some DSL variants, in particular the Digital Subscriber Line Asymmetric (ADSL), allows the superposition of the higher bandwidth digital data stream over the top of the traditional analog telephone service. This is achieved through the use of an easily available separator / combiner device installed in both WC and subscriber facilities. The voice communications can be provided by analog signal and by additional digital channels derived from the digital current (as explained above). However, as noted, the provision of analog voice service requires compatible POTS equipment in WC. Typically, this equipment is large and expensive and requires special connections, using timeshare division multiplexing for the rest of the telephone network. A telephone company that deploys the previous technology can offer the advantages of the ADSL analog POTS capability, but can not justify the cost of the traditional switching technology required in the Wiring Center. You need a mechanism that supports your investment in ^^^ technology based on package but still provide the benefits of traditional POTS, including continuous operation even when power fails at the customer's facility. For this purpose, the RDT 100 described above is modified and located in the WC shown, for example, in the reference number 68 in FIGURE 8. This component is called WC-RDT and is shown in the reference number 500. The WC-RDT 500 connects to a multiplexer in the cabling center, such as a DSLAM 64 and provides POTS interfaces for a large number of subscribers WC-RDT 500 is shown in FIGURE 9. It is similar to RDT 100 shown in FIGURE 2, although it lacks Ethernet port 170. WC-RDT 500 comprises a plurality of subscriber line interface circuit 150 each suitable for connection to the local loop links of a plurality of client facilities by means of a plurality of standard telephone ports (POTS) 510, and a plurality of encoders / decoders 160 for each connection to a subscriber line interface circuit 150. Each encoder / decoder 160 is capable of converting analog telephone signals received from an associated subscriber line interface circuit 150 into digital bit streams and converting a digital bit stream to analog telephone signals to be supplied to the line interface circuit of associate subscriber.

A controller 110 is coupled to the encoder / decoder 160 and to the interface circuits of the subscriber line 150. The controller 110 handles the interface of the voice-band packets between DSLAM 64 and the plurality of PTS ports 510. The different DSL 120 modulators can be provided in WC-RDT 500 to handle the highest capacity through multiple connections to DSLAM 64. The WC-RDT 500 is very compact and can be implemented in a platform mounted assembly factor such as that of very high port densities that can be achieved. Alternatively, the WC-RDT 500 functions can be integrated into DSLAM 64. Similarly, the operation of WC-RDT 500 is similar to that of RDT 100. The controller 110 handles the voice-band packet interface between DSLAM 64 and the plurality of standard telephone ports by: converting digital bit streams received from one or more encoders / decoders 160 into voice-band packets and coupling voice-band packets to the LPN for transmission to the guest digital terminal 200; and converting the demodulated voice-band packets received by DSLAM 64 to digital bit streams and coupling the digital bit streams to an appropriate one of the encoders / decoders 160. The WC-RDT 500 is powered by the power facilities of the center of 68 wiring where DSLAM 64 is located. These facilities are generally very reliable and also include backup batteries and generators to ensure operation even during commercial power failures. The WC-RDT 500 does not need to be equipped with connectivity for a LAN, unlike RDT 100. The wiring center 68 can be a large nearby building that houses the switching systems and other communications equipment, or it can be a cabinet or vault that hosts a DSLAM 64 that provides connections to subscriber cycles and includes a high availability power system. The WC-RDT 500 is connected to a DSLAM 64 by any available technology supported by DSLAM, including the same technology used by RDT 100. In fact, DSL technologies are somehow sensitive to distance and therefore tend to provide greater capacity bandwidth when the distance between two devices is shorter. When both of the WC-RDT 500 and DSLAM 64 are located in the same room of a wiring center installation, DSL technology can be expected to perform at its highest capacity. For example, using symmetric DSL technology available and relatively inexpensive, the bandwidth can be as high as 2,048 Mb / sec in each direction. It can provide more than one link between WC-RDT 500 and a DSLAM, thereby providing additional bandwidth in the connection. The WC-RDT 500 can use this bandwidth to to serve more POTS ports or lines for more subscribers.

In addition, multiple links between WC-RDT 500 and DSLAM 64 provide redundancy to maintain network reliability. Referring again to FIGURE 8, the WC-RDT 500 communicates with HDT 200 in the central switching facility 5 30. The telephone service for each POTS 510 WC-RDT port is provided by HDT 200 in accordance with the above operations described with reference to FIGURES 3 and 4. No additional transport or switching facilities are necessary. The HDT 200 communicates with WC-RDT 500 in the same way as does with RDT 100. However, WC-RDT provides service similar to POTS on ports 510 so that from the perspective of a subscriber connecting to TD 10 for a port 510, port 510 acts only as any port POTS Inclusive, a subscriber that also owns a RDT 100 can take advantage of the bandwidth provided to have multiple connections of voice and data lines and has backup POTS service on at least one line that will subsist on a failure of the RDT 100 due to lack of power, etc. The main purpose of the WC-RDT 500 is to provide the POTS service (analog telephone signals) to a plurality of TDs 10 located anywhere in the coverage area of a DSLAM 64. The CLEC has several options for providing the service. First, it supplies the conventional POTS service to the subscriber, the telephone company or CLEC connects a TD 10 and directly to a POTS port 510 in the WC-RDT 500 as shown in FIGURE 8. Second, it provides DSL data services and an individual POTS service line to a subscriber facility 5 such as that shown in reference number 700, a subscriber cycle is connected to a separator / combiner 600 in the wiring center 68, which separates the signal from the subscriber's installation in two instances, one of which is connected to a port POTS 510 of the WC-RDT and the other one is connected to a subscriber port of the DSLAM 64. In the installation of the subscriber 700, another separator / combiner 610 is provided which connects to the subscriber cycle and divides it into two instances to connect a TD 10 to provide the POTS service and a DSL 702 modulator. The modulator 702 can connect to PC 704 and / or to a LAN 706. Therefore, the subscriber 700 installation receives the conventional POTS service for a standard analog TD 10, and the DSL data service for PC 704 or LAN 706. Third, to provide multiline voice service, the POTS service and DSL data service for a subscriber installation such as that shown in reference number 800, the subscriber cycle is connected to a separator / combiner 620 in wiring center 68. Separator / combiner 620 separates the signal from the site subscriber in two instances, one of which is connected to a ^ ¡^^^^^ POTS port 510 of WC-RDT 500 and the other is connected to a DSLAM subscriber port 64. Similarly, at subscriber site 800, a separator / combiner 630 is provided to separate the signal in two instances, one of which is connected to RDT 100, and the other is connected to a TD 10 'analog standard. Thus, at the subscriber site 800, the TD 10 'receives the POTS service while the TDs 10 receives the voice service through the RDT 100. In addition, the DSL data services are provided to the LAN 12 or PC via of RDT 100. The WC-RDT 500 is perforated to provide several POTS connections. It is unlikely that all subscribers using TDs 10 and 10 '(connected to WC-RDT 500 via ports 510) will use their POTS connections simultaneously. Therefore, the capacity of the DSL link between DSLAM 64 and WC-RDT 500 can be oversubscribed. For example, if each DSL link can support 16 simultaneous voice conversations and the WC-RDT 500 services two DSL links between it and DSLAM 64, then CLEC can select to connect 128 POTS ports on WC-RDT 500, knowing that it will almost never have to more than a quarter of subscribers trying to use their POTS connections at the same time. As the number of subscribers in a region served by a particular wiring center (DSLAM or a group of DSLAMs) increases, additional WC-RDTs 500 can be installed.

In addition, each port POTS 510 in WC-RDT 500 is equipped with the protection circuit 320 to provide protection against lightning and overvoltage. The protection circuit of this type is well known in the art. This contrasts with the RDT 100 which does not include such a protection circuit over its POTS ports in SLICs 150 because the telephone services similar to POTS provided by RDT 100 are provided locally within a building. However, connections to WC-RDT 500 are made on "external plant facilities" (standard telephone lines). Those lines can be struck by lightning or otherwise damaged by a high voltage supply. Therefore, to protect the circuit of WC-RDT 500, the appropriate protection circuit is added between SLICs 150 and the associated connection port POTS 150 (FIGURE 2). In summary, the present invention is directed to a method for communicating voice to and from at least one client site over a local packet network (LPN) that supports a packet-based transport protocol. At a customer site, a plurality of telephone devices are interconnected for a local cycle link, such as DSL or a wireless local loop, connected to LPN. The analog telephone signals received from the plurality of the telephone devices are converted from voiceband and the voiceband packets are modulated for transmission by means of the local cycle link on the LPN. In the reverse direction, the modulated voice-band packets received from the LPN on the local cycle link are demodulated. The demodulated voice-band packets are converted to analog telephone signals for connection to one of the plurality of telephone devices. In addition to voice communication, the method also supports the communication of data to and from data devices (whose data devices can be part of a local area network) in the client's installation. The data packets from the data devices are modulated and transmitted by means of the LPN. In the reverse direction, the data packets received by the LPN are demodulated and coupled to the data devices (in the local area network) in the client installation. At the control site within the LPN (such as a data switch in the LPN) or connected to LPN (such as HDT or a PSTN switch in a central switching facility), the voice-band packets (and optionally the data packets) from the client site are received (via LPN if the control site is external to the LPN). The voice-band packets received from the customer site via LPN are converted to time division division multiplexed signals and are coupled to a public switched telephone network (PSTN) of voice switch in allocated time segments. The data packets received from the client site are (reformatted if necessary and) coupled by means of a data switch to a destination data network, such as a data network. In the reverse direction, the data packets destined for the client site are received from a source data network by means of the data switch connected to the source data network, such as the data network. The time division division multiplexed signals received from the PSTN switch intended for client installation are converted to voice-band packets and are coupled to the LPN 60 for transmission to the client site. Similarly, the data packets received from the source data network by means of the data switch are coupled to the LPN for transmission to the client site. In addition, a wiring center in or connected to LPN, the POTS service is provided for a customer site by connecting to one or more subscriber line ports of a multiplexer in the center of the cabling; providing one or more standard telephone ports for connection to the local loop links of one or more client sites; demodulating the modulated voice-band packets transmitted from the control site by means of the LPN and received on one or more subscriber line ports of the multiplexer; converting the demodulated voice-band packets to analog telephone signals for connection to one or more of the local cycle links of one or more client sites; converting the analog telephone signals received in the local cycle links from one or more client sites to voice-band packets and modulate the voice-band packets; and coupling the modulated voice-band packets to one or more subscriber line ports of the multiplexer for transmission over the LPN to the control facility. Another method in accordance with the present invention involves voice communication over a local packet network (LPN) to and from at least one client facility connected to the LPN by means of a local cycle link. In a wiring center in or connected to LPN, the following stages are executed: connect to one or more subscriber line ports of a multiplexer located in a wiring center; provide one or more standard telephone ports for connection in the local cycle links of one or more client sites; demodulating the modulated voice-band packets received from one or more subscriber line ports of the multiplexer; converting the demodulated voice-band packets to analog telephone signals for connection to one or more local cycle links of one or more client facilities; converting the analog telephone signals received in the local loop links in one or more client installations to voice-band packets and modulating the voice-band packets; and coupling the modulated voice packets to one or more subscriber line ports of the multiplexer for transmission over the LPN to the control site. With the control site within or connected to the LPN, the following control stages are executed: reception of voice-band packets from the wiring center via írs¿ ^ r- of the LPN; converting the voice-band packets received from the wiring center to timeshare division multiplexed signals and coupling timeshare division multiplexed signals to a public switched telephone network 5 (PSTN); and converting timeslot division multiplexed signals received from the PSTN switch destined to the wiring center into voice-band packets and coupling the voice-band packets to the LPN for transmission to the wiring center. Similarly, the present invention is directed to a system for communicating voice and data on an LPN to and from at least one client site (usually a plurality of client sites) connected to LPN by means of a cycle link. local, comprising: a remote digital terminal at the customer site, the remote digital terminal interconnecting with a plurality of telephone devices at the customer site for the local cycle link to transmit and receive the voice by means of the LPN; and a guest digital terminal in a control site inside or connected to the LPN that connects with the voice calls between the remote digital terminal and a public switched telephone network (PSTN) of the switch via the LPN. The system can support the additional transport of data between the data devices (which can be part of the of a local area network) at the customer site and a data network ? fc- siÉÉfesa «», "- inside the LPN or a data network connected to the guest digital terminal. The proper hardware and associated control functions required for the remote digital terminal and the guest digital terminal to transport voice traffic and data traffic to and from a customer site were described above. In addition, in this system, a remote digital terminal of the wiring center can be provided. The remote digital terminal of the wiring center connects to or is incorporated in a subscriber line access multiplexer (DSLAM) that is connected to or a part of the LPN. The remote digital terminal of the cabling center provides a standard analog telephone service between a plurality of standard telephone ports for connection to local cycle links of a plurality of client sites and the PSTN switch through the guest digital terminal. The central remote digital terminal of the cabling center comprises: a plurality of subscriber line interface circuits each suitable for connection to the local cycle links of a plurality of client sites by means of a plurality of standard telephone ports; a plurality of encoders / decoders for connection to a subscriber line interface circuit, each encoder / decoder being capable of converting the analog telephone signals received from an associated subscriber line interface circuit into digital bit streams and converting a stream of digital bits to analog telephone signals to be supplied to the associated subscriber line interface circuit; and a controller coupled to the encoder / decoder and the subscriber line interface circuits. The controller handles the interface of the voice-band packets between DSLAM and the plurality of standard telephone ports through: the conversion of digital bit streams received from one or more encoders / decoders to the voice / band packets and the coupling of the voice-band packets to the LPN for transmission to the guest digital terminal; and converting the demodulated voice-band packets received by the DSLAM to digital bit streams and coupling the digital bit streams to an appropriate one of the encoders / decoders. Another system according to the present invention communicates voice over an LPN to and from at least one client site connected to LPN via the local loop link, where the remote digital terminal is not necessarily located at the customer site . This system comprises a guest digital terminal in a control site inside or connected to the LPN that interconnects with the voice calls between the LPN and a public switched telephone network (PSTN) of the switch through the LPN; and a remote digital terminal from the wiring center that connects to or is incorporated into a digital subscriber line access multiplexer (DSLAM) that is connected to the LPN, the remote digital terminal of the wiring center that provides standard analog telephone service between a plurality of standard telephone ports suitable for connection to the local loop links of a plurality of subscribers and the PSTN switch through the host digital terminal. In this system, the remote digital terminal of the wiring center comprises; a plurality of subscriber line interface circuits each suitable for connection to a telephone device by means of a plurality of standard telephone ports; a plurality of encoders / decoders each for connection to a subscriber line interface circuit, each encoder / decoder capable of converting analog telephone signals received from an associated subscriber line interface circuit into digital bit streams and converting a current from digital bit to analog telephone signals to be supplied to the associated subscriber line interface circuit; and a controller coupled to the encoders / decoders and the subscriber line interface circuits. The controller handles the interface of voice-band packets between DSLAM and the plurality of standard telephone ports by: converting digital bit streams received from one or more encoders / decoders into voice-band packets and coupling voice packets -band to the LPN for transmission to the guest digital terminal; and converting the demodulated voice-band packets received by DSLAM into digital bit streams and coupling the digital bit streams to an appropriate one of the encoders / decoders. The present invention is further directed to an apparatus for voice and data communication between a local packet network (LPN) and an equipment in a central switching facility having a public switched telephone network (PSTN) connected to PSTN and a switch of data connected to a data network. The apparatus comprises an LPN interface device connected to the LPN to connect to the LPN to interconnect with the voice-band packets and data packets to and from the LPN; a PSTN interface device connected to the PSTN switch for interconnecting the signals to and from the PSTN switch; a packet conversion processor associated with the LPN interface device and the PSTN interface device that converts the voice-band packets into a suitable format for a transit through the LPN and a suitable time division division multiplexed signal format to attach to the PSTN switch and a controller. The controller is coupled to the LPN interface device for the packet conversion processor and the PSTN interface device and handles the voice-band packet interface between the LPN and the PSTN switch. The apparatus that supports data communication and comprises a data communication interface device íjgíj? áfe »¡jg¿¡ ^ connected to a data switch in the central switching facility and the packet conversion processor. The packet conversion processor converts the data packets between a format suitable for transit by means of the LPN and a format for coupling to the data switch. The host digital terminal controller is connected to the data switch interface device and controls the communications of the data packets received from the remote digital terminal by the LPN interface device for the data switch interface device and the communication data packet received from the data switch by the data switch interface device destined for the client site to the LPN interface device for transmission by means of the LPN. In addition, the present invention is directed to a method for communicating voice and data to and from a client installation over a local packet network (LPN), the client site that is connected to LPN by means of a local cycle link. The method comprises the steps of: receiving the voice-band packets in a control site from the client site by means of the LPN; converting the voice-band packets received from the LPN into multiplexed signals by timeshare division; coupling multiplexed signals by timeshare division into time segments assigned to a PSTN switch; and converting timeslot division multiplexed signals received from the PSTN switch destined for the client site into voice-band packets and coupling the voice-band packets to the LPN for transmission to the client site. The method further supports data communication by coupling data packets received at the control site from the client site by means of the LPN for a data network with or without the LPN; and coupling the data packets received from the data network destined for the client site to the LPN for transmission to the client site. The foregoing description is intended to be exemplary only and is not intended to limit the present invention in any way except as set forth in the appended claims. -. i a &

Claims

CLAIMS system for communicating voice over a local packet network (LPN) to and from at least one client site connected to the LPN by means of a local cycle link, characterized in that it comprises: a remote digital terminal at the customer's facility , the remote digital terminal interconnecting with a plurality of telephone devices in the client installation for the local cycle link in order to transmit and receive the voice through the LPN; and a guest digital terminal at the control site within or connected to the LPN interconnecting with the voice calls between the remote digital terminal and a public switched telephone network (PSTN) by means of the LPN.
The system according to claim 1, characterized in that the remote digital terminal comprises: a modulator for connection to the local cycle link to modulate the information packets for transmission over LPN and to demodulate the information received from the LPN; a plurality of subscriber line interface circuits each suitable for connection to a telephone device; a plurality of encoders / decoders each for connection to a subscriber line interface circuit, each encoder / decoder capable of converting analog telephone signals received from a subscriber line interface circuit into digital bit streams and converting a current of digital bits to analog telephone signals to be supplied to the associated subscriber line interface circuit; a controller coupled to the modulator, the encoders / decoders and the subscriber line interface circuits, the controller that handles the voice-band packet interface between the LPN and the client site by: converting received digital bit streams from one or more encoders / decoders in voice-band packets and coupling the voice-band packets to the modulator for transmission over the local cycle link to the LPN; and converting the demodulated voice-band packets received by the LPN modulator into digital bit streams and coupling the digital bit streams to an appropriate one of the encoders / decoders.
The system according to claim 1, characterized in that the remote digital terminal further comprises a network interface device for connection to a local area network in the client installation for coupling data packets from the local area network for transmission over the LPN and for coupling the data packets received from the LPN to the local area network, where the remote digital network controller is connected to the network interface device, the controller couples the data packets from the network interface device to the modulator for transmission over the local loop link for the LPN and couples the demodulated data packets received from the modulator to the network interface device.
The system according to claim 2, characterized in that the local cycle link supports a Digital Subscriber Line (DSL) and its associated transport protocols, and wherein the modulator comprises a DSL modulator.
The system according to claim 2, further characterized in that the local cycle link supports a wireless transport protocol and wherein the modulator comprises a wireless modulator.
The system according to claim 2, characterized in that the controller of the remote digital terminal assigns the priority of use of a bandwidth of the local cycle link between the voice traffic and the data traffic.
The system according to claim 6, characterized in that the remote digital terminator controller allocates the priority of use of the bandwidth of the local cycle link to the voice traffic on the data traffic.
The system according to claim 1, characterized in that the host digital terminal comprises: an LPN interface device for connection to the LPN to receive and transmit packets by means of the LPN; at least one PSTN interface device for coupling signals to and receiving signals from the PSTN switch; a packet conversion processor coupled to the LPN interface device and the PSTN interface device, the packet conversion processor that converts the voice-band packets between a format suitable for transit by means of the LPN and a multiplexed signal format by appropriate timeshare division for coupling to the PSTN switch; and a coupled controller for the PSTN interface device, the packet conversion processor and the LPN interface device, the controller handles the band-voice packet interface between the LPN and the PSTN switch.
The system according to claim 8, characterized in that the guest digital terminal further comprises a data switch interface device for interconnecting with the data packets between the guest digital terminal and a data switch connected to a data network. , the data switch interface device that is connected to the packet conversion processor that converts the data packets between a format suitable for transit by means of the LPN and a suitable format for coupling to the data switch, the controller of the guest digital terminal which is connected to the data switching interface device and which controls the communication of the data packets received from the remote digital terminal by the LPN interface device to the data switching interface device and the communication of the packets of data received from the data switch by the interface device with Data mutator destined for the client site to the LPN interface device for transmission by means of the LPN to the remote digital terminal.
The system according to claim 9, characterized in that the host digital terminal controller continuously monitors the amount of bandwidth used by the remote digital terminal for voice traffic to determine the availability of the remaining bandwidth on the link of local cycle for data traffic, and limits the data traffic destined to the client site so that a predetermined portion of the total bandwidth available for the client site remains available for voice traffic.
The system according to claim 8, characterized in that the host digital terminal controller continuously monitors the amount of bandwidth used by the remote digital terminal for voice traffic in order to determine the availability of the remaining bandwidth over the local cycle link for data traffic, and wherein the host digital terminal controller sends a message to a data switch in the LPN that indicates the amount of bandwidth available for data in the local loop link.
12. The system according to claim 1, characterized in that it further comprises a remote digital terminal of wiring center that connects to or is incorporated in a digital subscriber line access multiplexer (DSLAM) that is connected to the LPN, the remote digital terminal of cabling providing a standard analog telephone service between a plurality of standard telephone ports suitable for connecting cycle links of a plurality of client sites and the PSTN switch through the guest digital terminal.
The system according to claim 12, characterized in that the wired central remote digital terminal comprises: a plurality of subscriber line interface circuits each suitable for connection to the local cycle links of a plurality of client sites per means one of a plurality of standard telephone ports; a plurality of encoders / decoders each for connection to a subscriber line interface circuit, each encoder / decoder capable of converting analog telephone signals received from an associated subscriber line interface circuit into digital bit streams and converting a current of digital bits in analog telephone signals to be supplied to the associated subscriber line interface circuit; a controller coupled to the encoders / decoders and the subscriber line interface circuits, the controller that handles the interface of the voice-band packets between DSLAM and the plurality of standard telephone ports by: the conversion of received digital bit streams from one or more encoders / decoders in voice-band packets and coupling the voice-band packets to the LPN for transmission to the remote digital terminal; and converting the demodulated voice-band packets received by the DSLAM into digital bit streams and coupling the digital bit streams to an appropriate one of the encoders / decoders.
The system according to claim 12, and which is characterized in that it further comprises a separator / combiner in the center of a cabling having a first port coupled to a local cycle link of a client, a second port coupled to DSLAM , and a third port coupled to one of a plurality of standard telephone ports from the remote digital terminal of the wiring center.
The system according to claim 14, and characterized in that it further comprises a separator / combiner at a client site having a first port coupled to a local cycle link of a client, a second port coupled to the terminal remote digital, and a third port suitable for connection to a telephone device.
The system according to claim 14, and characterized in that it further comprises a separator / combiner at a client site having a first port coupled to a local cycle link of a client, a second port coupled to the DSL modulator. on the client site, and a third port suitable for connection to a telephone device.
17. A system for voice communication over a local packet network (LPN) to and from at least one client site connected to the LPN by means of a local site link, characterized in that it comprises: a guest digital terminal in a control site within or connected to the LPN that interconnects with voice calls between the LPN and a public switched telephone network (PSTN) commutes via LPN; and a wired center remote digital terminal that connects to or is incorporated into a digital subscriber line access multiplexer (DSLAM) that is connected to the LPN, the remote wiring center digital terminal that provides a standard analog telephone service between a plurality of standard telephone ports suitable for connection to the local loop links of a plurality of subscribers and the PSTN switch through the guest digital terminal.
18. The system according to claim 17, characterized in that the remote digital terminal of the wiring center comprises: a plurality of subscriber line interface circuits each suitable for connection to a telephone device by means of a plurality of standard telephone ports; a plurality of encoders / decoders each for connection to a subscriber line interface circuit, each encoder / decoder capable of converting analog telephone signals received from an associated subscriber line interface circuit into digital bit streams and converting one digital bit stream in analog telephone signals to be supplied to the associated subscriber line interface circuit; and a controller coupled to the encoders / decoders and the subscriber line interface circuits, the controller that handles the voice-band packet interface between DSLAM and the plurality of standard telephone ports by: converting received digital bit streams from one or more of the voice-band packet encoders / decoders and coupling of the voice-band packets to the LPN for transmission to the guest digital terminal; and converting the demodulated voice-band packets received by the DSLAM into digital bit streams and coupling the digital bit streams to an appropriate one of the encoders / decoders.
The system according to claim 17, and characterized in that it further comprises a separator / combiner in the cabling center having a first port coupled to a local cycle link of a client, a second port coupled to DSLAM, and a third port coupled to one of the plurality of standard telephone ports of the remote digital terminal of the wiring center.
The system according to claim 19, and characterized in that it further comprises a separator / combiner at a customer site having a first port coupled to the customer's local loop link, a second port coupled to the remote digital terminal. and a third port suitable for connection to a telephone device.
The system according to claim 19, and which is characterized in that it further comprises a separator / combiner at a client site having a first port coupled to the local cycle link of a client, a second port coupled to a modulator at the client site, and a third port suitable for connection to a telephone device.
22. A method for communicating voice and data to and from at least one client site over a local packet network (LPN) that supports a packet-based transport protocol, each client site comprising a plurality of telephone devices , the method is characterized in that it comprises the steps of: at a customer site: converting the analog received telephone signals from the plurality of telephone devices into voice-band packets and modulating the voice-band packets for transmission over the LPN by means of of a local cycle link between the client site and the LPN; demodulate the modulated voice-band packets received from the LPN over the local cycle link; converting demodulated voice-band packets into analog telephone signals for connection to one of the plurality of telephone devices; at a control site within or connected to the LPN: receive voice-band packets from the client site via the LPN; converting the voice-band packets received from the client site into multiplexed signals by timeshare division and coupling multiplexed signals by timeshare division in a public switched telephone network (PSTN); and converting timeslot division multiplexed signals received from the PSTN switch destined for the client site into voice-band packets and coupling the voice-band packets to the LPN for transmission to the client site.
The method according to claim 22, characterized in that at the client site, it further comprises the steps of: modulating the data packets received from the data devices in the client site for transmission over the LPN via the link of the local cycle; and demodulate the data packets received from the LPN in the local cycle link and attach the data packets to the data devices in the client site; and at the control site, further comprising the steps of: receiving the modulated data packets from the client site by means of the LPN and coupling the modulated data packets to a destination data network by means of a switch of data; and receiving the data packets destined for the client site from a source data network by means of the data switch and coupling the data packets received from the data switch to the LPN for transmission to the client site.
The method according to claim 23, characterized in that the client site further comprises the step of assigning the priority of use of a bandwidth of the local cycle link between the voice traffic and the data traffic.
25. The method according to claim 24, characterized in that the assignment step comprises assigning the priority of use of the bandwidth of the local cycle link to the voice traffic over the data traffic.
26. The method according to claim 23, characterized in that the control site further comprises the steps of: continuously monitoring the amount of bandwidth of the local cycle link used by the customer site for voice traffic to end to determine the availability of the remaining bandwidth over the local cycle link for data traffic; and limiting the data traffic to the customer site from the LPN so that a predetermined portion of the total bandwidth available to the customer site on the local cycle link remains available for voice traffic.
27. The method according to claim 23, characterized in that in the control site, it also comprises the steps of: continuously monitoring the amount of bandwidth of the local cycle link used by the client site for voice traffic to to determine the availability of the remaining bandwidth over the local cycle link for data traffic; send a message to the data switch in the LPN indicating the amount of available bandwidth for the data traffic destined for the client site.
28. The method according to claim 22, characterized in that the functions specified for the control site are executed by a data switch that is part of the LPN.
29. The method according to claim 22, characterized in that the functions specified for the control site are executed by the PSTN switch in a central switching facility.
30. The method according to claim 22, and characterized in that the functions specific to the control site are executed by a host digital terminal that connects to the PSTN switch in a central switching facility.
31. The method according to claim 22, characterized in that the local cycle link supports a Digital Subscriber Line (DSL) and its associated transport protocols.
32. The method according to claim 32, characterized in that the local cycle link supports a transport protocol based on a wireless packet.
The method according to claim 22, in a wiring center, which is characterized in that it further comprises the steps of: connecting to one or more subscriber line ports of a multiplexer in the wiring center; provide one or more standard telephone ports for connection to the local cycle links of one or more client sites; demodulating the voice-band packets transmitted from the control site by means of the LPN and received on one or more subscriber line ports of the multiplexer; converting the demodulated voice-band packets into analog telephone signals for connection to one or more local cycle links of one or more client sites; converting the received analog telephone signals into the local loop links of one or more client sites into voice-band packets and modulating the voice-band packets; coupling the modulated voice-band packets to one or more subscriber line ports of the multiplexer for transmission over the LPN to the control site.
34. A method for voice communication over a local packet network (LPN) to and from at least one client site connected to the LPN by means of a local cycle link, which is characterized in that it comprises the steps of: a wiring center: connect to one or more subscriber line ports of a multiplexer located in the wiring center; provide one or more standard telephone ports for connection to the local cycle links of one or more client sites; demodulating the modulated voice-band packets received from one or more subscriber line ports of the multiplexer; converting the demodulated voice-band packets into analog telephone signals for connection to one or more local cycle links of one or more client sites; converting the received analog telephone signals into the local loop links from one or more client sites to voice-band packets and modulating the voice-band packets; and coupling the modulated voice-band packets to one or more subscriber line ports of the multiplexer for transmission over the LPN to the control site; at a control site within or connected to the LPN: receive the voice-band packets from the wiring center via the LPN; converting the voice-band packets received from the wiring center into time division division multiplexed signals and coupling time division division multiplexed signals to a public switched telephone network (PSTN); and converting timeslot division multiplexed signals received from the PSTN switch destined for the wiring center into the voice-band packets and coupling the voice-band packets to the LPN for transmission to the wiring center.
35. An apparatus for voice communication between a local packet network (LPN) and equipment in a central switching facility comprising a public switched telephone network (PSTN) connected to PSTN, the apparatus is characterized in that it comprises: LPN interface connected to LPN to interconnect with the voice-band packets to and from the LPN; a PSTN interface device connected to the PSTN switch for interconnecting the signals to and from the PSTN switch; a packet conversion processor coupled to the LPN interface device and the PSTN interface device, the packet conversion processor that converts the voice-band packets between a suitable format for transit between the LPN and a division multiplexed signal format Timeshare suitable for coupling the PSTN switch; and a controller coupled to the LPN interface device, to the packet conversion processor and to the PSTN interface device, the controller that handles the interface of the voice-band packets between the LPN and the PSTN switch.
36. The apparatus according to claim 35, and further characterized in that it further comprises a data switching interface device connected to a data switch in the central switching facility and to the packet conversion processor of converting the data packets. data between a suitable format for transit through the LPN and a suitable format for coupling to the data switch, the host digital terminal controller which is connected to the data switch interface device and which controls the communication of data packets. data received from the remote digital terminal by the LPN interface device for the data switch interface device and the communication of data packets received from the data switch by the data switch interface device intended for the customer site to the LPN interface device for transmission by means of the LPN.
37. The apparatus according to claim 35, characterized in that the LPN interface device is an optical link that implements an asynchronous transfer mode (ATM) protocol.
38. The apparatus according to claim 35, characterized in that the PSTN interface device comprises a plurality of T-1 interfaces.
39. The apparatus according to claim 36, characterized in that the controller continuously monitors the amount of bandwidth of a local cycle link used by a customer site for voice traffic to determine the availability of the remaining bandwidth over the link local cycle for data traffic, and limits the data traffic destined to the client site from the LPN so that a predetermined portion of the total available bandwidth of the client site in the local cycle link remains available for voice traffic.
40. The apparatus according to claim 36, characterized in that the controller continuously monitors the amount of bandwidth of a local cycle link used by a customer site for voice traffic to determine the availability of remaining bandwidth over the local cycle link for data traffic, and generate a message that is sent through the data switch to the LPN indicating the amount of bandwidth available on the local cycle link for data traffic destined to the client site .
41. In a system for data and voice communication to and from a customer site over a local packet network (LPN), the customer site that is connected to the LPN by means of a local cycle link, in a site control inside or connected to the LPN; the method is characterized in that it comprises the steps of: receiving the voice-band packets in a control site of the client site by means of the LPN; converting the voice-band packets received by the LPN into multiplexed signals by timeshare division; coupling multiplexed signals by timeshare division into time segments assigned to a PSTN switch; and converting timeslot division multiplexed signals received from the PSTN switch destined for the client site to voice-band packets and coupling the voice-band packets to the LPN for transmission to the client site.
42. The method according to claim 41, and characterized in that it further comprises the steps of: coupling the data packets received at the control site from the client site by means of the LPN to a data network within or outside the LPN; and coupling the data packets received from the data network destined for the site of the LPN for transmission to the client site.
43. The method according to claim 42, and which is characterized in that it further comprises the steps of: continuously monitoring the amount of bandwidth on the locrl cycle link used by the customer site for voice traffic in order to determine the availability of the remaining bandwidth over the local cycle link for data traffic; and limiting the data traffic destined to the client site from the LPN so that the predetermined portion of the total bandwidth available for the client site on the local cycle link remains available for voice traffic.
44. The method according to claim 41, and which is characterized in that it further comprises the steps of: continuously monitoring the amount of bandwidth over the loco-cycle link 'used by the client site for voice traffic to determine the availability of the remaining bandwidth over the local cycle link for data traffic; and send a message to the LPN indicating the available bandwidth for traffic destined to the client's site.
45. The method according to claim 42, characterized in that the functions specified by the control site are specified by a data switch that is part of the LPN.
46. The method according to claim 42, characterized in that the functions specified by the control site are executed by a PSTN switch in a central switching facility.
47. The method according to claim 42, and characterized in that the functions specified for the control site are executed by a host digital terminal that connects to the PSTN switch and to a data switch in a central switching facility.