Abstract: A call offering method for use when a directory number is shared by an analog station and an ISDN station. The ISDN station has multiple call appearances of the shared directory number that are linked logically to multiple analog station states that correspond to the offering of multiple calls.

Abstract: A call processing method where a transferring station can be disconnected from a call after the call is transferred to a third station, but where the call is automatically returned to the transferring station in response to either disconnect signaling or other predefined signaling, e.g., a flash or a dual-tone-multi-frequency (DTMF) tone, without requiring any station to dial the transferring station. The transferring station is for a subscriber to a new, transfer-with-return feature. The feature is invoked for the call either in response to a signal from the transferring station requesting invocation of the feature or because the subscriber has only the transfer-with-return feature and no other transfer feature. The call is also returned in response to a busy or no answer condition of the third station.

Abstract: An arrangement where display control data which has been developed off-line, and which specifies the content and sequence of the display screens required to lead a customer through activation of a plurality of telephone features, is received and stored by an analog display station either at an initialization or a feature update of the station. The display control data is used by the station to communicate information relating to a particular feature to a user via the station display. The user inputs, e.g., keystrokes, received after each display screen, are stored by the station, and after the sequence has been completed, all such stored user inputs are rapidly transmitted to the switching system to effect the particular feature. Significantly, the switching system telephone feature software is not involved until after all stored user inputs are transmitted. Therefore, there is no need to modify existing software as long as the user inputs are not changed.

Abstract: A telephone ringing arrangement where a non-sinusoidal ringing voltage waveform is used that has significantly longer intervals during which the waveform is near zero as compared to a sinusoidal waveform. A connect interval is defined as the time during which the magnitude of the non-sinusoidal ringing voltage waveform remains less than a predefined threshold. The connect interval includes a zero-crossing of the ringing voltage waveform. For an illustrative ringing voltage waveform, the zero-crossing has zero slope. A ringing relay is controlled to connect the non-sinusoidal waveform to a telephone line such that the connection time, including relay bounce time, occurs only during one of the connect intervals. Similar principles may be used based on a disconnect interval of the ringing current waveform, to reduce transients on disconnection.

Abstract: A method where a telecommunication system records a message spoken by a caller and plays the recorded message to a human attendant for use in routing an incoming call without the attendant having to answer the incoming call. The system then responds to input from the attendant by playing the message to a third party to familiarize the third party with the call before the caller is removed from hold and the call is completed to the third party. In this manner, the first person that the caller speaks with has already listened to the message. The message is supplemented with additional voice messages or conversations as the call is handled by multiple parties. Wordspotting is used as the initial message is being recorded; if the wordspotting is successful, the recorded message is routed to a third party without any attendant involvement and the third party is familiarized with the call.

Abstract: An adaptive clock recovery arrangement for deriving a synchronous clock from an asynchronous, packet stream such as an asynchronous transfer mode (ATM) cell stream. The deviation in the magnitude of information stored in a first-in-first-out memory is continually monitored, and the synchronous clock frequency, referred to as the adaptive line clock frequency, is adjusted in a plurality of modes, under the control of a processor. The adjustment is made in response to a detected increasing condition of the monitored deviation. The adjustments are open-loop adjustments made without continually adjusting the adaptive line clock frequency based on the monitored deviation. Damping is substantially reduced compared with "conventional" PLL arrangements because the open-loop adjustments result in a rapid frequency correction with perfect or nearly perfect deadbeat damping, i.e. without the frequency oscillations that continue after the correct frequency is reached in closed-loop arrangements.

Abstract: An expanded telemetry feature protocol allowing the provision of additional transport capabilities: 1) switch alert of CPE or voice equipment, 2) activation of other switch capabilities, 3) a barge-in capability, and 4) a broadcast capability. A telemetry function identification is included in the protocol to define a plurality of telemetry applications. Other extensions to the protocol allow sequential broadcast of voice or data to a list of destinations, operation with an analog display station interface (ADSI) station, and subaddressing to specify particular destinations.

Abstract: A tone burst generator where a continuous tone voltage is applied across two series-connected semiconductor switches each having an ON state and an OFF state. A first control circuit controls the state of the first switch and the variable impedance in an intermediate region between its ON and OFF states to cause gradual, well-defined OFF/ON and ON/OFF transitions of the first switch. As a result of these first switch transitions, a voltage tone burst is generated that has precisely defined edges to eliminate clicking noise. The continuous tone voltage is of only one polarity--it has a non-zero DC component and an AC component having a peak-to-peak variation less the twice the magnitude of the non-zero DC component. A second control circuit controls the state of the second switch and the variable impedance in an intermediate region between its ON and OFF states to cause well defined ON/OFF and OFF/ON transitions of the second switch.

Abstract: A method for use by a switching system in controlling the downloading of parameters to customer stations. The notification of stations due to a change in a configuration group is performed at a controlled rate and accordingly any reduction in call processing due to the parameter downloading of customer stations is limited. The controlled rate notification is performed in accordance with two lists that are maintained by the switching system and used to track the active/inactive status of customer stations and to order the notification of active stations and the status checking of inactive stations.

Abstract: A growable packet switching arrangement where the distribution network blocking probability is substantially reduced because the network has both switch links and chute links, and the network nodes include both a switching element interconnecting successive stage switch links and a plurality of non-switching, chute connections interconnecting successive stage chute links. A network node can transfer a packet, being received on a switch link, to any selected one of the chute connections of that node for transmission on a chute link. The network nodes are relatively simple and inexpensive because they store only the first few bits needed to route an ATM cell. The blocking probability is further reduced when the number of chutes per node is increased. The number of chutes may be based, for example, on the number of switch link inputs per node.

Abstract: An optical receiver, e.g., receiver 10 (FIG. 1), has differential optical input beams and generates an electrical output. The voltage at an electrical node between series-connected optical detector diodes is clamped within a predefined voltage range by series-connected clamping diodes, to prevent the voltage from increasing when consecutive logic one optical input beams are received. Variable bandwidth and low energy dissipation are achieved since the resistors of high input impedance and transimpedance receivers are not required. A second optical receiver, e.g., receiver 20 (FIG. 2) is a monolithic, diode-clamped S-SEED with complementary optical input beams and complementary optical output beams.

Abstract: A growable packet switching arrangement where the number, S, of distribution network stages is reduced by bounding S according to log.sub.2 (max(L,N))<S+1<[log.sub.2 (max(L,N))].sup.2 /2. Since the distribution network is made up of stages of opto-electronic nodes and interconnecting free-space optical link stages, there is no need to transmit input signals using different frequencies. Input signals are instead distinguished based on their spatial location. Accordingly, there is no receiver tunability restriction on L, the number of inputs. Further, because signals are regenerated at each network stage and there is only a 3:1 power loss (approximate) at a given stage, high signal/noise ratios and corresponding low bit error rates are achieved.

Abstract: A call waiting deluxe method where a switching system forwards calls to a service node that provides specialized call processing, e.g., processing requiring text-to-speech, to a number of switching systems without requiring modification of the hardware design of those systems. Only calls to busy called stations are forwarded to the service node using a call forwarding-busy line feature to avoid unnecessary delays and excessive service node traffic for normal calls. The service node uses the same directory number that was initially dialed for the call, in invoking a call waiting-originating feature which takes precedence over the call forwarding-busy line feature and results in the transmission of a call waiting signal to the called station. The service node obtains the calling party name from a database and responds to a flash signal from the called station by speaking the calling party name to the called party.

Abstract: A call coverage arrangement where a covering terminal has, for each covered terminal, a single monitor lamp that not only indicates the overall or collective busy or idle status of the call appearances on the covered terminal but also the collective ringing status. Distinct visual signals are provided at the monitor lamp to indicate either a ringing while idle or a ringing while busy status. This allows all calls to be answered promptly and efficiently by a secretary in a manner which, from a human factors standpoint, is similar to the call coverage provided with key systems.

Abstract: An exemplary packet processing apparatus where a large number of comparisons can be made concurrently in bit-parallel fashion by partitioning the comparison functionality to two optoelectronic integrated circuits, and interconnecting the two circuits using free space optics. Illustratively, different embodiments are used to perform one-to-many or many-to-one comparisons by developing multiple copies of one value for concurrent comparison with many possible values. The invention is more generally applicable to other comparison applications where one-to-many or many-to-one comparisons are made.

Abstract: A low blocking packet distribution network which is implemented in optics. The network has both switch links and chute links, and the network nodes include both a switching devices interconnecting successive stage switch links and a plurality of non-switching, chute connections interconnecting successive stage chute links. A network node can transfer a packet, being received on a switch link, to any selected one of the chute connection means of that node for transmission on a chute links. The network nodes are relatively simple and inexpensive because they store only the first few bits needed to route an ATM cell. The blocking probability is further reduced when the number of chutes per node is increased. The number of chutes may be based, for example, on the number of switch link inputs per node.

Abstract: An arrangement where a switching system receives parameter(s) concerning the traffic expected on a call from a first user to a second user, the system determines a priority for the call based on the expected traffic parameter(s), and information is transmitted to the second user during the call based on the determined priority and with less than a maximum jitter. The priority is selected from a predefined priority table based on expected traffic parameters. The priority table is usable for both constant bit rate and statistical calls.

Abstract: A multi-stage network which achieves the same overall connectivity as known networks but where individual switching nodes have no input selectivity and no output selectivity. Each node is enabled or disabled to control communication therethrough in response to a single control signal. The functionality of a switching network is achieved by controlling which nodes are enabled rather than specifying connections of particular node inputs and outputs to be effected by the nodes. In a photonic network embodiment, each network node is implemented using a single symmetric self electro-optic effect device (S-SEED).

Abstract: An arrangement where a plurality of digital signal processors cooperate in the performance of a digital signal processing function. The processors are interconnected by means of a synchronous network which provides time division multiplexed communication links between processors for communicating intermediate processing results therebetween. The synchronous network includes a plurality of port circuits each associated with one of the processors. The network generates timing signals defining frames of time slots and defining superframes comprising N frames. Each port circuit can control the transmission of digital data from a memory of its associated processor during M1 time slots of each superframe. Each port circuit can also control the writing of digital data to its associated processor during M2 time slots of each superframe. The value of N, the number of frames per superframe, is programmable. The values of M1 and M2 are also programmable for each port circuit.

Abstract: A method of establishing an N time slot connection through first and second, single-buffered time slot interchangers where the time slots interconnecting the two time slot interchangers, referred to herein as network time slots, are chosen in accordance with particular selection criteria such that all N time slots received by the first time slot interchanger in a single frame, are also transmitted from the second time slot interchanger in a single frame.