Abstract: A method and apparatus for testing the operation of a videophone wherein a rotating body having a visual pattern of contrasting visual shapes is placed within the visual field of the videophone. The videophone is connected to a communication path which in turn is connected to a display. A control device varies at least one of the rotational speed of the rotating body and the characteristics of the communication path, while an image of the rotating body is observed on the display.

Abstract: A system and method for multi-wavelength modulated optical communication uses the same optical fiber without the use of multiple tuned lasers. A transmitter includes an optical comb generator and a digital modulator. The optical comb generator generates a broad spectrum of wavelengths using a white noise generator. A Fabry-Perot cavity filters the wavelengths to form a set of equally spaced resonances lambda-1 . . . lambda-n. The comb generator is locked to a particular wave length by comparing each carrier or the composite mean of the carriers to an optical reference. An error signal is generated and fed back into the into comb generator. The resonances are split into n-channels using a tree splitter. Each channel is modulated in the digital modulator. The channels are summed as an optical signal and amplified to ensure proper power levels prior to being fed to an optical fiber.

Abstract: A database management system and method for operation allow both key compression and quick indexed retrieval of nodes. The system includes a processor, memory and a modified skip list data structure with compressed search keys. The prior art skip list structure is modified so that each node has only one other node pointing to it. This allows search keys to be compressed based on the key of the previous node. Key compression allows the data structure to use less memory than is otherwise possible.

Abstract: The present invention provides to a distributed restoration scheme a set of timers so that multiple senders and choosers can more fairly contend for the spare capacity of a telecommunications network. In particular, a preactivation timer would force a sender that had reserved excess spare capacity of the network for restoring its own failed links to release any unused spare capacity prior to the time that it terminates its operation, provided that it has found an alt-route or alt-routes for its failed link. An alarm validation timer and a hold off timer in the invention scheme further provide for respective validation and detection that a detected fault is not transient or intermittent in nature and that a restoration process is needed to find the alt-routes.

Abstract: In a telecommunications network having a plurality of intelligent nodes interconnected by multiple communication channels, alternate paths and spare channels are set up for restoring traffic disrupted by failure to one or more of the communications channels. The alternate paths may be set up irrespective of the number of custodial node pairs, also referred to as leader/follower or sender/chooser pairs, that could simultaneously be involved in the restoration operation. The interconnected nodes have bi-directional working and/or spare channels. There is stored at each node in the network participating in the recovery operation a spare channel manifest for each of the leader/follower combinations. The first end node, or leader node, of every identified failed channel initiates a request message for each disrupted working channel to set up an alternate path.

Abstract: A plurality of release action tables are maintained in the switching nodes of a telecommunication network, e.g SS7, ISDN, one table for each trunk group. The table indicates desired actions or treatments to be taken for failed calls, each identified by a cause condition. Upon receiving a cause condition expressed as a code at a switching node, a release action table index is accessed to identify the release action table for the trunk group experiencing the cause condition. The cause code is compared against entries in the release action table by a control program included in the switching node. Based upon such comparison, the table indicates to the network the corrective action to be taken to remedy the failed call condition. Changes to the network for failed call conditions are accomplished by altering the data in the release action table rather than changing network.

Abstract: A system and method for selected audio response to a telephone call that results in an unsuccessful connection. If a condition within the set of conditions is satisfied based on attributes associated with the caller or the telephone call, an action list associated with the satisfied condition is executed. The action list can comprise a selected audio response that is transmitted to the caller of the unsuccessful connection.

Abstract: The present invention telecommunications system provides validation of authorization codes input by a user for placing a call from a service area of a first telecommunications service provider with a calling card issued by another telecommunications service provider. The present invention allows the subscriber to place a special service call irrespective of whether the signaling protocol of the first service provider is different from the service provider to which the subscriber is a customer of. If the protocol of one telecommunications service provider is indeed different from the other service provider, a gateway residing in an intelligent service network node would convert the signaling protocol of the first service provider into a signaling protocol that is compatible with the other service provider.

Abstract: A conference system provides dial-out conference calls to participants who use various virtual private network dialing plans as well as place non-plan calls, such as Direct Distance Dialing and International Direct Distance Dialing. The conference system recognizes non-identical VPN dialing plans, as well as PSTN numbers, which all originate on a single Dedicated Access Line (DAL). When a dial-out conference call is originated on a DAL, a switch performs a database query to determine a VPN dialing plan. Based on a code provided along with the dialed telephone number, the database identifies the number as belonging to a particular VPN dialing plan and translates it into a physical termination. Alternatively, if the code indicates that the number does not belong to a VPN dialing plan, i.e, a DDD or IDDD number, it is unmodified by the database. Either translated or untranslated number is then returned to the switch for subsequent network routing to a physical termination.

Abstract: The present invention telecommunications system provides validation of authorization codes input by a user for placing a call from a service area of a first telecommunications service provider with a calling card issued by another telecommunications service provider. The present invention allows the subscriber to place a special service call irrespective of whether the signaling protocol of the first service provider is different from the service provider to which the subscriber is a customer of. If the protocol of one telecommunications service provider is indeed different from the other service provider, a gateway residing in an intelligent service network node would convert the signaling protocol of the first service provider into a signaling protocol that is compatible with the other service provider.

Abstract: All nodes on a malfunctioned communications circuit of a communications network are enabled to identify the location of the fault causing the circuit malfunction. Upon detecting an incoming signal impairment on the circuit, each node on the circuit first assumes that the failure is on the segment of the circuit immediately upstream thereof, and accordingly sends an identifier of that fault location to its downstream nodes. Each node periodically repeats sending its identifier to its downstream nodes. A node that has sent its identifier at least a predetermined number of times without receiving a similar identifier from another node upstream thereof or without having detected a normal signal during all that time is determined to have sent out an identifier that correctly identifies the fault location on the communications circuit.

Abstract: A card for tonal entry of PIN codes into a telephone is provided. The keys of a key entry device are contacted in a proscribed sequence to enter a number into the card with each use of the card. The keyed in number is compared with a number stored in the card. If the numbers are the same, an acknowledgement tone is sent. Upon obtaining of the acknowledgement tone, the annunciator in the card is held to the telephone mouthpiece and activated by the user to produce a tonal representation of the PIN number. If an improper number sequence is keyed in by the user, the card produces a warning signal requiring reentry of a number. After three or four successive failures of the user to enter the correct number, the card is disabled and a new one has to be obtained by the cardholder.