Abstract: An arbitration mechanism provides quality of service guarantees for time-sensitive signals sharing a local area computer network with non-time-sensitive traffic. Device adapters are placed at all access points to an Ethernet network. The device adapters limit admission rates and control the timing of all packets entering the network. By doing so, collisions are eliminated for time-sensitive traffic, thereby guaranteeing timely delivery. A common time reference is established for the device adapters. The time reference includes a frame with a plurality of phases. Each of the phases is assigned to a device adapter. Each device adapter is allowed to transmit packets of data onto the network only during the phase assigned thereto. The length of the phases may be modified in accordance with the number of packets to be transmitted by a particular device adapter. A master device adapter may be appointed to synchronize each of the device adapters.

Abstract: A multi-circuit emulating line card is installable in a single line card slot of the backplane of digital switch, and is configured to emulate the functionality of each of a plurality of digital switch line cards, respectively associated with plural digital subscriber circuits served by the switch. In the course of emulating these plural line cards, the multi-circuit line card provides connectivity between each digital subscriber circuit and a digital carrier communication link to plural digital subscriber loop circuits, such as BRITE cards of a remote terminal site. The line card of the invention also includes network and subscriber circuit-associated metallic link impedance simulation circuits for terminating a metallic test bus.

Abstract: A port for connecting a node to a network loop is disclosed. The port includes a detect element, a frame termination generator, a buffer data generator, a switching element, and a control element. The detect element monitors data from the node and sets an error flag when invalid data is received at the port. The frame termination generator generates frame termination primitives. The buffer data generator generates buffer data. The switching element has a control input, an output, and a plurality of data inputs. Each of an output of the node, the upstream node, the frame termination generator, and the buffer data generator is connected to a corresponding data input. The control element is connected to the detect element and the control input of the switching element. The control element selects, according to the error flag, one of the data inputs of the switching element. The selection connects to the output of the switching element to be output by the port to a downstream node.

Abstract: A RAM-based interrupt-driven interface device is disclosed for establishing a communication link between a universal serial bus (USB) host and a microcontroller device for providing a control function, the interface device being operative to receive digital information in the form of command, data and control packets from the host and to process the packets and communicate the processed digital information to the microcontroller device, and in response thereto, the microcontroller device being operative to communicate digital information to the interface device for processing and transfer thereof to the host.

Abstract: Methods and apparatus for efficiently communicating across an asymmetric digital subscriber loop are disclosed. According to one aspect of the present invention, a method for communicating between a computer in a central office and a remote computer across DSL communications links involves sending a first set of data from the central office computer across a first DSL communications link. The first DSL communications link couples the central office computer to a switch. The method also includes selecting a second DSL communications link, which couples the switch and the remote computer, and sending the first set of data from the switch to the remote computer across the second DSL communications link.

Abstract: A PC-based home automation system uses a low data-rate transport layer and COM-based software components for control of devices in a home automation network. The home automation system is merged with a messaging-based HAVi-network that uses IEEE 1394 as a high data-rate transport layer. The HAVi-network controls audio/video equipment in a home entertainment system. The home automation services and devices are registered as a HAVi-compliant elements with the HAVi network's FAV or IAV device. The home automation resources (devices and services) have both COM OLE Automation Interfaces and HAVI-compliant interfaces to permit control of the home automation system from the HAVi-network.

Abstract: A new architectural arrangement for network elements deployed in a central office (CO) is disclosed. The architectural arrangement involves dividing the network elements into an optical layer comprised of elements that have optical signal interfaces and switch optical signals, an opto-electrical layer comprised of elements that have optical signal interfaces and switch electrical signals, and an electrical layer comprised of elements that have electrical signal interfaces and switch electrical signals. The opto-electrical layer connects the optical and the electrical layer, and also connects lower-rate optical links into the CO. This layered architectural arrangement allows for more efficient use to be made of the small number of high-rate ports supported in the optical layer, and for the off loading of switching responsibility from both the optical and the electrical layers. This, in turn, improves the overall performance and capacity of the CO.

Abstract: A network node supports switching fixed length information cells between a source unit and a destination unit. The invention uses two lookup tables called the active and the standby calendars for each of said output line. Each entry in the calendars represents the position of one cell in the output cell stream which will be sent onto said output lines. While the active calendar is controlling the network cell multiplexing onto a node output line, the standby calendar is updated at each traffic change by looking for a calendar free position for the new traffic starting with a targeted theoretical entry position. A Free Location Table (700) is used, storing the calendar organized by pages. The standby calendar updating starts with reading a Free Location Table page pointed at by the most significant bits of the theoretical entry. Should said page contain only ones (i.e., no free cell position) looking for the nearest page containing at least one zero (i.e.

Abstract: A method for coordinating and controlling multiple data streams representing a data transmission session that terminate in different termination units (such as network access servers) using a virtual data stream tunnel is presented. The data streams are transmitted over two or more links, collectively forming a "bundle. One of the termination units that receives a data stream is designated as the termination unit to receive and reconstruct a call. The designated termination unit is the "owner" of the bundle. A termination unit that is a not a bundle owner creates a virtual tunnel to the termination unit that is the bundle owner, and sends data streams through the virtual tunnel to the bundle owner to reconstruct the call. The designated termination unit reconstructs the data streams for the bundle and directs the bundle to a destination.

Abstract: A plurality of terminals communicate. One terminal belongs to a plurality of groups of terminals. In the communication apparatus, a terminal information memory stores terminal identifiers. A sending section sends the communication information with the terminal identifiers of other terminals participating in one group to the other terminals. A receiving section receives information sent by the other terminal. A group discrimination section compares the received terminal identifiers with the stored terminal identifiers, and discriminates the group from which the received information was communicated according to the comparison.

Abstract: A method and apparatus for supporting connections on multipoint-to-point topologies is disclosed. A cell scheduler schedules packets from incoming VCCs for transmission on the order that a complete frame is available. Cells are received from a plurality of virtual channel connections. The cells for each of the virtual channel connections are stored in a buffer until a complete packet has been received. When a buffer accumulates a complete packet of cells for one of the virtual channel connections, the cells are scheduled for transmission. A complete packet is determined by looking at a packet type identification field. Cells forming a first packet for a first virtual channel connection are transmitted continuously until all the cells have been transmitted. A next available complete packet of cells is transmitted after the first packet of cells has been transmitted. A determination is made whether a cell is a data cell, an OAM cell, a Resource Management cell or a reserved cell.

Abstract: A line interface unit terminates individual subscriber lines and supports conventional telephone service and high speed data service. It provides an interface between subscriber customer premises equipment and central office equipment. The use of large diplex filters is not required in order to terminate subscriber lines at the central office while providing high speed data services.

Abstract: A method and system (100) for monitoring quality of service within a network of computers. The method includes a step of providing a network of computers, each being coupled to each other to form a local area network. The network of computers has a firewall server (110) coupled to the network of computers and a traffic management tool coupled to the firewall server. The method also includes implementing traffic control for incoming and outgoing information using one or more rules.

Abstract: A method and apparatus is provided for interfacing a plurality of ISDN lines from a telephone company central office to equipment which transmits video data, such as videoconferencing equipment. A single telephone wiring jack is directly coupled to two, three, or four ISDN lines without conversion to S/T channels. The single telephone wiring jack is coupled to an interfacing device which converts each ISDN line format into a format compatible with the videoconferencing equipment, such as the Multi-Vendor Interface Protocol format. Rather than using conventional wiring pin-outs for the single telephone wiring jack, all pins of the jack may be allocated to carrying ISDN data. The inventive method and apparatus avoids the expense of various conversion devices and wiring of separate telephone jacks, and permits as many ISDN lines to be allocated as are needed to support a desired bandwidth.

Abstract: The present invention enables multiple analog telephones to communicate over a two-wire line via the Asymmetric Digital Subscriber Line (ADSL) standard. The analog signal from a standard analog telephone appliance is converted in a terminal adapter associated with the telephone to digital data packets and transmitted over the telephone lines to a central office (CO) using the ADSL standard. Plain Old Telephone System (POTS) frequencies are separated from digital data frequencies by a filter and passed to each terminal adapter on a separate line. On a power-off condition, the terminal adapter connects the telephone to this line. The present invention enables the user to add additional lines without additional wiring into the premises.

Abstract: In one embodiment of the invention, an access point for use in a powerline based network includes first physical layer circuitry to interface with a powerline and second physical layer circuitry to interface with an antenna. The access point also includes circuitry to interface between the first and second physical layer circuitry. The first and second physical layer circuitry and the circuitry to interface between the first and second physical layer circuitry allow an untethered electrical device to have data communication through the powerline with an electrical device tethered to the powerline. Under another embodiment of the invention, a powerline based network includes a powerline and an access point connected to the powerline and capable of wireless communication.

Abstract: A contact apparatus for a network in which a plurality of outlets are connected with each other by a repeater through a bus. A cable contains a bus to transmit signals and a power supply line. When the cable is connected with one of the outlets, the device concerned participates in the network and the power supply voltage is supplied to the device. Data can be exchanged between the devices only by connecting the cable with the outlets.

Abstract: A system for managing access by a plurality of terminal devices to an access line of a public switched telephone network (PSTN). The system comprises a SAU (service access unit) connected to the access line, and a FSP (full service provider) which is interconnectable through a call connection within the telephone network to the SAU. The SAU includes a plurality of interfaces each adapted to communicate with a respective terminal device connected thereto. This combination of the SAU and the FSP interconnected through the PSTN enables each of the terminal devices to access or be accessed from multiple service networks. The management system effectively provides multiple independent telephony "service" over the single access line by sharing the available bandwidth of the PSTN connection between the SAU and the FSP amongst the various terminal devices as required.

Abstract: An apparatus and methods for communicating data over a voice-band communications loop are disclosed. The apparatus includes transceiver circuitry, a backplane interface, backplane interconnection circuitry, and signaling circuitry. The transceiver circuitry transmits and receives voice-band modulated data over the communications loop. The backplane interface provides for physical interconnection to the backplane. Backplane interconnection circuitry couples the transceiver circuitry and the backplane interface to each other for data transmission to enable the exchange of digital data between the transceiver and the backplane. The signaling circuitry transmits and receives POTS call control signals over the communications loop. A method for receiving voice-band data is disclosed.

Abstract: High-speed digital transmission can be achieved with existing phone lines and HDSL chipsets. Two original ISDN signals [4,5] at a rate of 160 kbps are multiplexed by a MICS card [6] of a signal provider [1]. The resulting digital signal is transported over a twisted cable pair [2] which has an approximate maximum length of 16 kft. At a receiving end, the signal is demultiplexed and regenerated by a subscriber's MICS card [7]. The subscriber's MICS card is line-powered via the cable [2] to avoid dependence upon local power. The regenerated signals are transmitted over two ISDN cables to remote premises which can be as far as 18 kft away.

Abstract: An on-demand system controlling on-demand services between a media server and subscriber terminals, the system includes an ATM-HUB unit which performs a path setting operation in accordance with a PVC (Permanent Virtual Connection) function, and a path setting management server. The ATM-HUB unit has previously set paths between the subscriber terminals and the path setting management server and between a controller of the ATM-HUB unit and the path setting management server in accordance with the PVC function at a time of setting environments of the system. A subscriber terminal supplying a media transmission request to the path setting management server via the path set between the subscriber terminal and the path setting management server.

Abstract: Conflicts are resolved between competing nodes in a multi-node communications network. After a first node in the network requests an initiation of communications with a target node, the requesting node may simply initiate the requested communications with the target node if the target node is not busy. If the first node determines that the target node is busy, it proceeds to resolve the conflict. Namely, the first node repeats the process of waiting for a first delay then requesting initiation of communications with the target node. After each unsuccessful attempt, the first delay is successively increased. As an example, the delay may be increased exponentially, with a controlled randomness added. After a or more queued messages to other nodes. Following this, the first node performs another sequence to initiate communications with the target node, successively increasing the delay between unsuccessful attempts, as before.

Abstract: To cascade a network line concentrator and a plurality of terminals, the network connection circuit installed in each of the plurality of terminals forwards first data in a direction from the line concentrator to the neighboring terminal, provides the first data for the terminal, forwards second data in direction from the neighboring terminal to the network line concentrator, and transfers third data from the terminal toward the network line concentrator.

Abstract: An integrated multiport switch (IMS) in which one combinational logic and register arrangement is provided for executing similar media access control (MAC) functions for a plurality of switch ports. The current access state at each of a plurality of switch ports is maintained at a single state storage location, whereby access of a stored port MAC state and update thereof is simplified. Access to state storage in coordination with the single common combinational logic and register arrangement enables MAC functions for each of the plurality of ports to be performed on a time shared basis to maximize efficiency of use of chip resources and architecture space.

Abstract: A system is provided for creating a tunneling service from the use of a traditional tunneling protocol, such as the layer two tunneling protocol (L2TP). In particular, the L2TP tunneling protocol, which is designed to go point-to-point between an L2TP Access Concentrator (LAC) and an L2TP Network Server (LNS), is abstracted so that L2TP becomes an access protocol to a tunneling service. A new L2TP tunnel merger and management (LTM) service is created which severs the tight configuration relationships between LAC and LNSs. Only a tight configuration between an LAC and its LTM edge device and between an LNS and its LTM edge device is required. An internal trunk protocol (INT protocol) carries needed information between LTM edge devices to establish ingress/egress L2TP access calls inside of separate L2TP access tunnels on opposite LTM edge devices.

Abstract: A method for controlling customers' access to services on a broadband network. The method uses a circuit identifier, unique to each customer, to compare service requests with service entitlements. The network provider flows the circuit identifiers to the service providers where relationship between the circuit identifiers and the service entitlements is established in service orders. Service providers flow the service orders back to the broadband network though a standard business system interface. The relationship between the circuit identifiers and the service requests is accomplished at the Broadband Digital Terminal that interface the customers to the broadband network. The circuit identifiers also permit sorting of data bases containing logs of service requests and logs of maintenance actions.

Abstract: A distributed digital switching system is provided that includes a plurality of service controllers (20) which are interconnected to each other through a network (10). A network arbitrator is provided that controls the flow of traffic on the network (10). Each of the service controllers (20) is operable to provide a switching configuration between inbound data to the service controller (20) and network terminations associated with each of the service controllers (20). A processor (150) on each of the service controllers (20) controls the operations thereof with the voice information stored in a memory (208) which can be configured with a circuit (204). Each of the service controllers (20) has associated therewith a conference circuit for defining and creating a conference that can access all inbound data and provide interconnections therebetween and output this on a single outbound conference channel. There can be multiple conferences created at each service controller (20).

Abstract: In an ATM switching network, a limitation of traffic in an ATM switching apparatus is relaxed. In an ATM switching network capable of allocating a plurality of communication channels to a terminal unit of one subscriber, when the terminal of this subscriber requests setting of the plural communication channels, a traffic amount of the communication channels proposed to the ATM switching apparatus is declared as a total amount of the respective communication channels. The ATM switching apparatus measures a total traffic amount of the plural communication channels set in response to the request made by the terminal unit, and limits the traffic of the plural set communication channels in such a manner that the measured traffic amount becomes lower than, or equal to the traffic amount declared through the terminal unit.

Abstract: A method of encoding data into a digital sequence to be transmitted over the DTN so as to cause the DTN's codec to generate a multiple modulus M-ary signal in a manner that will facilitate efficient data transmission and recovery (decoding) by the distant end receiver, even in the presence of robbed-bit signaling (RBS). The preferred embodiments provide an apparatus and method of converting blocks of binary data to a corresponding block of M.sub.1 -ary, M.sub.2 -ary, . . . , M.sub.n symbols using Multiple Modulus Conversion (MMC) to maximize the data rate, while minimizing the required Signal-to-Noise Ratio (SNR) to achieve a desired error rate, in a system having a transmitter connected to the DTN via direct digital access and a receiver connected over a conventional analog subscriber line. A subset of codec codewords is used to represent the M-ary signals.

Abstract: A system and method of transmitting data cells are disclosed. The system includes a data transmitting and receiving unit including transceiver circuitry, a main backplane interface, and backplane interconnection circuitry. The transceiver circuitry transmits and receive data cells over the data link, the main backplane interface provides physical interconnection to the backplane, and the backplane interconnection circuitry transmits and receives cells. The main backplane interface including at least one cell signal terminal and at least one operations data signal terminal. The operations data signal terminals are separate from the cell signal terminals. The operations data signal terminals and the cell signal terminals are configured to connect to mating connectors on a backplane. Backplane interconnection circuitry couples the transceiver circuitry to the main backplane interface.

Abstract: A simple and inexpensive integrated way for connecting a variety of standard computer devices, including networking integrated circuit devices, to other standard and customized integrated circuit devices, is provided as follows. An integrated circuit device has an interface, the interface is capable of transferring data from a MAC layer to a PHY layer, and also is capable of transferring data from the PHY layer to the MAC layer. There is a pin on the integrated circuit device for setting the interface in a first mode or a second mode, and when the interface is in the first mode the interface is capable of transferring signals between a MAC device and a PHY device, and when the interface is in the second mode the interface is capable of transferring signals between a first MAC device and a second MAC device.

Abstract: A computer telephony integration exchange system in which the user can easily use the functions of function codes even though he/she does not know the relevant function codes of the simple digital exchange system.

Abstract: A communication system is formed by an ATM network and a multiplexing device suitable for such a system. The ATM network includes a plurality of nodes and links which connect various access points within the network. The multiplexing device includes a plurality of access terminals which transmit information across the network to output terminals linked to the access points via demultiplexing devices. Information transmitted across the network is routed using cells containing a destination identifier which defines the connection between two of the access points and the multiplexing device.

Abstract: A wideband communication system is achieved with apparatus coupled to a wire pair, such as the wire pair provided by a communication services provider at a customer's premises. Disclosed is an embodiment which illustratively employs CDMA as the modulation schema for communicated signals and which, by this means, achieves a bandwidth in the range of 1 MHz. Specifically, a modem is interposed between the wire pair and the customer premises devices which modulates applied signals using code division modulation. The customer premises devices interface with the modem through interfaces that are specialized for the type of device that does the communication, and through a controller that manages the interactions. Illustratively, the apparatus includes the ability to provide one or more POTS ports, an ISDN port, and an asynchronous digital port. Protocol with the provider's network is effected through a signaling channel that occupies a preselected frequency band.

Abstract: A method for transmitting information signals in a subscriber terminal network wherein the network is between an exchange and the individual subscribers and which is used in the course of the worldwide expansion of the digital telecommunication networks for the transmission of digital signals. In order to be able to guarantee optimal transmission rates, measurements of the transmission parameters of the subscriber terminal lines are carried out and, according to the standard provided by these measurements, a maximum bit rate is determined for each subscriber terminal line.

Abstract: A telecommunications system includes an access terminal coupled to subscriber lines, a local exchange carrier (LEC) network, and a channel unit card coupling the access terminal to the LEC network. The channel unit card includes a processor configured to convert call processing signals received from the LEC network and formatted according to a protocol used by the LEC network to a message-oriented signal whose format is independent of the protocol used by the LEC network. The message-oriented signal then can be delivered to the access terminal. The channel unit card processor is further configured to convert message-oriented signals representing call processing communications received from the access terminal and having a format independent of a protocol recognized by the LEC network to one or more signals formatted according to the protocol recognized by the LEC network. The signals converted to the format recognized by the LEC network then can be routed to the LEC network.

Abstract: A telecommunications network (80, 120, 140) for enabling resale of local services includes a distributed switching system (88) owned by an incumbent local exchange carrier which has a call control computing platform (100) coupled to a digital loop carrier (86), where the digital loop carrier (86) is coupled to a plurality of telephone service subscribers (82) of the incumbent local exchange carrier as well as telephone service subscribers (84) of a competitive local exchange carrier. A local switch (104) owned by an incumbent local exchange carrier is coupled to the digital loop carrier (86).

Abstract: A data communication system in which a data communication address for a communication terminal can arbitrarily be changed whenever the communication terminal is used. This data communication system includes a database 60 for storing a corresponding relation between an identifier 41 of a communication terminal 40 and a plurality of data communication addresses used for the communication. The database 60 stores a corresponding relation between the identifier 41 of the communication terminal and the data communication addresses during a period of use thereof in accordance with instructions from the communication terminal 40. When incoming data is received that is directed to certain data communication address, a network switching device 50 obtains an identifier corresponding to the certain data communication address and transmits the data to the communication terminal with the identifier.

Abstract: A digital cordless telephone system comprises a multiplicity of subscriber cordless handsets (HS's) with a subscriber number of a private automatic branch exchange (PABX) being assigned to one or more of the HS's, a plurality of base stations (BS's), each of the BS's being coupled with one or more of the HS's by radio channels for controlling a radio link between each of the BS's and each of the HS's, and a system connecting unit coupled with the BS's and the PABX for allowing only authenticated HS's to initiate outgoing calls and for keeping track of each of the HS's to set up calls for the HS's whenever the HS's are within the service area of one of the BS's.

Abstract: In an apparatus and a method for interfacing a private exchange to an ISDN, the apparatus controls intralayer and interlayer entity communications to interface the private exchange to the ISDN. The apparatus is disposed in a universal card slot of a subscriber shelf of the private exchange in the form of a card to accommodate an ISDN terminal in the private exchange or connect the private exchange to an ISDN public network, thereby enabling voice and data communications.

Abstract: An ATM line concentration apparatus includes first and second transmission path termination circuits, an ATM switch, and a signaling termination circuit. Information for execution of signaling as a procedure for establishing a switched virtual channel with respect to an ATM switching unit or a plurality of subscriber terminals in response to a call generated from the ATM switching unit or the plurality of subscriber terminals is transmitted by using the ATM switch and the signaling termination circuit through the first and second transmission path termination circuits.

Abstract: A low cost, high speed multimedia data network is disclosed. The network preferably includes a fiber optic data bus arranged in a star topology configuration. Various types of devices or nodes may be placed in communication with the bus via a specially designed interface. The interface allows a device to communicate with the high speed network without requiring that the device have the processing power to receive and transmit data according to the protocols and demands of the network. The interface may be configured to match the complexity of its associated device. For intelligent devices, the interface may allow some of the network-related functions to be performed by the device itself. For non-intelligent (or "dumb") devices, the interface performs substantially all of the network-related functions.

Abstract: A circuit arrangement is provided for connecting a personal computer (PC) to a port of a key telephone system via an adapter circuit which also interfaces a digital key set to the port. The adapter circuit is connected to the computer via an RS-232 single channel data link. The PC is programmed to generate and receive a serial data stream into which are encapsulated messages relating to link control and telephone functionality. The adapter circuit is also programmed to receive and generate the serial data stream. The data rate through the adapter circuit and the telephone system and hence to a remote computer is dependent on the utilization of the attached key set by the user to make a call.

Abstract: A multipoint multichannel connection device for line-connecting communication terminals at multiple points and a central unit through an integrated services digital network which has a function of communicating the number of a source communications terminal as source number information includes a source number information identifying section incorporated in a central unit, which identifies source number information from the integrated services digital network unit process arriving channels for which source number information is recognized as being identical, as arriving channels from the same communications terminal. As a result, the central unit identifies arriving channels from a plurality of communications terminals individually and then processes them without communicating source number information with the communications terminals.

Abstract: A virtual ethernet interface interconnects a first computer at a customer premise with an ethernet local area network (LAN) at a central office that is connected to the customer premise via a digital subscriber line (DSL). The virtual ethernet interface comprises a virtual interface card connected to the first computer and a physical interface card connected to a second computer that is in communication with the ethernet hub. On start up, the central office computer sends the MAC address associated with the ethernet interface of the physical interface card back to the virtual interface card of the first computer. Thus, the virtual ethernet interface allows the first computer to form ethernet frames using the MAC address of the physical interface card so that it appear as though they were originated from the second computer. Further, the first computer can receive frames taken from the ethernet LAN by the physical interface card and transmitted to the virtual interface card over the DSL link.

Abstract: An apparatus connects a data processing system (10) with an analog telephone line and/or an ISDN line. The apparatus modulates and demodulates data from the data processing system (10) to either of the two different telephone protocols without adding unnecessary expense or noise to the system.

Abstract: A network device for interconnecting computer networks, the device including a bridge having a plurality of ports through which network communications pass to and from the bridge, the bridge also including a first interface enabling a user to partition the plurality of bridge ports into a plurality of groups, wherein each group represents a different virtual network, wherein the bridge treats all ports within a given group as part of the virtual network corresponding to that group and the bridge isolates said virtual networks from each other, whereby any communications received at a first port of the bridge are directly sent by the bridge to another bridge port only if the other bridge port and the first bridge port are part of the same group.

Abstract: An ISDN communication apparatus of the present invention can accept termination of information when this information is received even when there is no idle B channel. The ISDN communication apparatus comprises at least one ISDN line interface (1) connected to the ISDN line, a multiplex link forming circuit (3) connected to a plurality of B channels to form a logical link through the multiplex conversion and a point R interface (2) connected to the logical link formed of the multiplex link forming circuit. When the D-ch interface(12) detects the distant party address from the termination information from the distant communication apparatus, the main control circuit (4) compares the distant party address with the previously set reference address to detect whether these are matched or not.

Abstract: A method for operating an ISDN PBX?110! for connecting M BRI lines?13-15! connected to a central office?12! to N terminals?21-28, 31-38, 41-48! connected to the PBX?110! (N>M), such that any B channel of any of the BRI lines?13-15! can be connected to any terminal utilizing a connect in accordance with Bellcore National Standard NI-2. Each of the terminals?21-28, 31-38, 41-48! is associated with one, and only one, of the BRI lines?13-15!. The present invention achieves its advantages over the prior art by defining a plurality of EKTS groups?1-4!. Each of the EKTS groups?1-4! includes at least one of the terminals?21-28, 31-38, 41-48! associated with each of the BRI lines?13-15!. When an incoming call is received for a terminal associated with a BRI line that is currently busy, the call is connected by emulating a connection to a second terminal that is assigned to free BRI line and which is also assigned to the EKTS group to which the first terminal is assigned.

Abstract: A terminal adapter for ISDN services is implemented using a digital signal processor rather that a general purpose microprocessor, and provides normal terminal adapter functionally while at the same time substantially reducing part count and increasing flexibility and reliability. The terminal adapter uses a pipelined operating system involving a series of hierarchical menus of subtasks to perform the various functions required for ISDN operability.