Abstract: A system and method of preventing call congestion on outgoing trunks of a local telephone exchange is provided. A virtual trunk group representing a percentage of the total trunk capacity is assigned at the local exchange for carrying calls which are likely to cause congestion. In one embodiment of the invention, call segregation is achieved by using the prefixed dialling code 1+1 followed by the destination number. In another embodiment of the invention, segregation is dynamically achieved using Advanced Intelligent Network (AIN) routing.

Abstract: An "Intelligent" telecommunications network comprises a plurality of switching units interconnected by links and connected to a central computer unit by a data communication system. For dynamic routing of a call, a first switching unit responds to a destination address in a call to attempt a direct link to a neighboring switching unit and, in the event that the attempt is unsuccessful, issues to the central computer unit a message containing the destination address. The central computer unit uses the destination address to identify the unsuccessful link; (ii) updates a routing database to identify the link as unavailable; (iii) determines an alternative route for the call using a tandem node and (iv) compiles a return message including a network address for a tandem switching unit and transmits it to the first switching unit. The latter attempts to route the call via a link to the tandem unit which attempts to complete the call by a direct link to the destination switching unit.

Abstract: A method of providing number portability for the treatment of calls from a calling party to a specific number of a called party is disclosed. An Initial Address Message (IAM) containing the calling and called party's numbers to enable said call to reach said terminating office is forwarded from an originating office to a terminating office. Once the IAM is received at the terminating office, a determination of whether the call is directed to a portable number is made. If the call is directed to a portable number, a release message containing an indication that the called party number is a portable number and containing new routing information is forwarded from the terminating office to the originating office. A new IAM is then sent from the originating office to a terminating office associated with the routing information.

Abstract: A plurality of M PBXs are coupled to a plurality of N nodes forming a Distributed Transit Private Branch Exchange (PBX). The plurality of N nodes are located remotely from each other and form a wide area network. Each node is coupled to predetermined ones of the other nodes via separate links so that each node is able to communicate with all other nodes. One or more D-channel Server Modules (DSMs) are located in predetermined nodes of the plurality of N nodes. Each DSM is associated with a plurality of D channels which are each coupled to a separate interface device in the same node or different node by means of a link for receiving and transmitting signaling data to one of an associated predetermined PBX of the plurality of PBXs.

Abstract: A method and system of managing call forwarding includes establishing criteria for selecting among possible links between nodes for forwarding calls from an originating node to a destination node. In the preferred embodiment, the selection of the possible links is made at a called node from which the call is to be forwarded. Based upon the administrable criteria, there is a determination as to whether an intermediate node along the call path between the originating node and the called node is to be selected for initiating the forwarding path. If an intermediate node is selected, a request is transmitted to the intermediate node to initiate the forwarding path to the destination node. On the other hand, if no intermediate node is selected, a determination is made as to whether to initiate the forwarding path from the originating node or from the called node. Again, the determination is made according to the administrable criteria.

Abstract: A system and method for remote call control, including providing a tandem switch to control independent legs of a telephone conversation. The switch connects an organization's telecommunications system (Centrex or PBX), with cellular or wireless telephones. The switch facilitates a call coverage plan for an organization, and provides the ability to selectively seize and dial a plurality of telephone terminals as needed in a manner based at least in part upon instructions received from a remote or wireless terminal.

Abstract: A method and system of improved routing to WATS completes calls through a wide area telephone service using indirect routing. When a call is placed from a calling telephone station to a called telephone station, a telephone network attempts to route the call from the originating switch, on which the call entered the network, to a local exchange carrier serving the called station. If other routing paths in the network are unavailable or unsuccessful, a network processor recommends a routing from the originating switch to the local exchange carrier through a tandem switch and the WATS line of another telephone network. This capability provides a reduced incidence of blocked calls, such as may result from telecommunications system outages.

Abstract: A system and method for automatic call distribution targeting users in workgroups wherein the users utilize either wired or wireless communications tools. Users are chosen via a rule-based selection process including access to a database of user and caller-screened information. The system is compatible with available and developmental hardware platforms for call centers and mobile workers including SS7/AIN, computer telephony interfaces, direct cellular network connections, PBX and centrex-based systems.

Abstract: The instant invention provides a number of approaches in which a virtual homing to overcome outages can be achieved whereby a single terminating destination or an egress node can be formed from multiple terminating switches that would allow the network to route calls based on the capacity, economics or survivability of those switches to accept the call. A first network processor (NP) approach includes a number of methods that relies on the processor of the dynamic control routing (DCR) network, and the switch based routing that directs a call to the appropriate terminating node. A second approach of the instant invention is based on the data access point (DAP) of the network. This DAP approach utilizes the intelligence of the network and requires that all call queries be directed to the DAP for locating the appropriate terminating switch for routing the call.

Abstract: A system for employing a computer to control a device to provide a plurality of services for a plurality of entities. Each entity corresponds to exactly one of the services and each service has its own copy of the code which defines the service. The system associates a process which executes the service with each service. The code for a service defines a finite state machine which is continually executed by the service's process. While in a given state, the finite state machine may traverse a decision graph which is directly accessible to the process. Actions to be taken on traversal of a node of the decision graph may be defined in the finite state machine. The service's process communicates with other processes and with itself by means of interprocess messages. Each state of the finite state machine contains event handlers for responding to messages received by the service's process.

Abstract: A method of providing multi-switch business group (MBG) services at each of a plurality of locations is described. The MBG services can be provided for calls made from a calling party served by an originating switch at one location to a called party served by a terminating switch at a location serviced by an inter-exchange carrier (IEC). When the calling party goes off-hook, a determination is made of whether the call is made from a centrex line. Digits dialed by the calling party are then collected at the originating switch. A determination is then made of whether the dialed digits contain an access code indicative that the call is to be routed to one of the plurality of locations which is served by an IEC. If the call is to be routed via an IEC, the initial address message (IAM) required for IEC calls, is modified to include MBG service information. This will permit MBG services to be offered between the calling party and the called party over public CCS7 trunks routed via an IEC.

Abstract: A network management node (10) collects trunk loading data and switch congestion data from switches in a telecommunication system. Path loading vectors (52, 56,) constraint vector (66), and switch congestion vector (76) are calculated and compared to yield potential intermediate switch candidates having the lowest available trunk traffic loading and switches with the lowest congestion consistent with other constraints associated with intermediate switch selection. Trunk groups with increasing levels of traffic and switches with increasing levels of congestion are incrementally tested in order to yield potential intermediate switch candidates whereby call distribution to the lightest loaded trunks and switches is accomplished.

Abstract: A dynamically controlled routing (DCR) telecommunications network is formed by a plurality of network switching elements, each connected to at least one other by at least one circuit group for carrying calls therebetween, and a network processor connected to the network elements by data links. Each network switching element determines, for each call, a neighboring network element to which it should be routed. It does so by accessing a routing table which contains alternate routes to be attempted if a direct route either does not exist or cannot be used. The routing tables are updated periodically by the network controller. The DCR network functions as a group of nodes interconnected by links and routing takes place on a node-to-node basis.

Abstract: Customers that have groups of stations served from multiple digital switching systems, which frequently include mixtures of PBXs and Centrex, require capabilities that will allow those station groups to operate as one global group. This invention permits customer station groups, including PBXs and Centrexes interconnected by private facilities or by the public switched telephone network (including long distance carriers), to act as a single entity that supports integrated voice and data communications. Advantageously, Integrated Services Digital Network (ISDN) Primary Rate Interface (PRI) facilities are used to carry the communications and signaling to and from the PBXs.

Abstract: A telecommunication switching system having switching nodes that perform adaptive routing by utilizing the fact that the switching nodes are arranged in a first and a second hierarchy. In addition, each switching node maintains routing information based on telephone and switching node numbers which identify the switching nodes. A destination switching node transfers its routing information back to an originating switching node which combines that routing information with its own in order to determine shorter call paths for subsequent call routing. The first hierarchy is a dialing plan hierarchy having groups of switching nodes at each dialing plan level. The second hierarchy is a switching node hierarchy based on the switching node number of each switching node with at least one switching node of the switching node hierarchy being at a different level in the dialing plan hierarchy.

Abstract: A system for distributing a numbering plan to switching nodes which are organized in a dialing plan hierarchy and for allowing an individual switching node to redistribute blocks of numbers to other switching nodes upon requests from those switching nodes to own the requested blocks of numbers. Further, the dialing plan hierarchy is automatically established upon system initialization with each switching node determining its position in that hierarchy. In addition, a switching node that needs to use only one number of a block owned by another switching node can request permission from the other switching node to use that telephone number for a telephone connected to the switching node. Such a use is referred to as hosting the telephone number.

Abstract: A digital tandem channel unit installable in an intermediate central office of a digital carrier telephone network maintains the digital format of the T1 traffic in the course of a DS0 tandem cross-connect, so as to eliminates the possibility of corruption of voice/data traffic, as may occur in a conventional `analog` office cross-connect tandem pair due to quantization errors introduced into the data stream in the course of the digital to analog conversion of the data. Also, the invention incorporates control software in each tandem channel unit's micro-controller that allows it to respond to analog tone signalling test procedures initiated from either two or four-wire channel ports of network access equipment.

Abstract: A special host routing code is transmitted from the remote switch to a host switch which advises the host switch whether the call is to be made to a subscriber local to the host switch or to a remote subscriber via an external telephone system trunk connected to the host switch. In the set up of a call, two steps are executed in addition to those of a normal switch-to-switch communication which functions to set up a path from the remote switch through, or to the host switch. These steps are the outpulsing of a host routing code from the remote switch over a specified trunk to the host switch and waiting for an acknowledgement, such as a wink (temporary line open or close condition). This causes the host switch to set up a cut-through path through the host switch, allowing the remote switch to tandem through the host switch. The digits dialed by subscribers on both switches to affect similar types of calls are therefore similar, and similar types of switches can be used for the remote and host switches.

Abstract: The present invention is a novel technique in the automatic control of the size of a network of remote attendants in accordance with varying incoming call traffic patterns. The remote attendants are on the public switched telephone network. The system routes incoming calls via outgoing lines to the attendants. The remote attendants can receive a "stream" of incoming calls within one outgoing call to an attendant. The remote attendants are kept on-line, that is, "off-hook" as long as the amount of waiting time between incoming calls does not exceed a maximum waiting interval set by the supervisor. When the attendant has to wait for the next incoming call for longer than a maximum waiting interval set by a supervisor, then the attendant can be automatically disconnected from the system. As call traffic increases, the system can automatically redial the remote attendant to be re-networked so as to receive another "stream" of incoming calls.

Abstract: The present invention is a telecommunications control system for accepting a plurality of multi-purpose stations for use as attendant stations in an attendant-service complex. Calls directed to the system from originating stations are received by a line connection subsystem having a plurality of connection controllers. Each connection controller in this first plurality of connection controllers provides for cooperating with a respective one of the plurality of multi-purpose stations defining opposite ends of a call connection path. Each of these connection controllers has a controllable switch for opening the call connection path and releasing the respective multi-purpose station. The line connection subsystem further includes a second plurality of connection controllers, each connection controller provides for cooperation with a respective one of the plurality of originating stations in defining opposite ends of a call connection path.

Abstract: In a private communication network (10) served by a provider of call interconnection services, e.g., a carrier service node (15), the number of trunks (50-52) used within a call path is reduced without affecting the private nature of the private network. The service provider serves customer calls by means of a service node controller (SNC 40)--a switch such as a PBX. The SNC directly interconnects trunks (50,51) that connect it with a call-source and a call-destination node (20,21) of the customer, without routing the call through the customer's tandem node (24). The SNC merely queries the customer's tandem node over a control link (53), such as an ISDN D channel, to obtain requisite call-routing information from the customer's database (60). The customer retains ownership and control of the tandem node and its database, thereby preserving the private nature of the private network.

Abstract: The present invention is a telecommunications control system for accepting a plurality of multi-purpose stations for use as attendant stations in an attendant service complex to service calls directed to the system from originating stations. This system comprises a first plurality of connection controllers. Each connection controller in this first plurality of connection controllers provides for cooperating with a respective one of a plurality of multi-purpose stations in defining opposite ends of a call connection path. Each of these connection controllers has controllable switching means for opening the call connection path and releasing the respective multi-purpose station. The system provides for security against use of any of the multi-purpose stations within the attendant service complex by an unauthorized person. This system further includes a second plurality of connection controllers.

Abstract: In a private communication network (10) served by a provider of call interconnection services, e.g., a carrier service node (15), the number of trunks (50-52) used within a call path is reduced without affecting the private nature of the private network. The service provider serves customer calls by means of a service node controller (SNC 40)--a switch such as a PBX. The SNC directly interconnects trunks (50,51) that connect it with a call-source and a call-destination node (20,21) of the customer, without routing the call through the customer's tandem node (24). The SNC merely queries the customer's tandem node over a control link (53), such as an ISDN D channel, to obtain requisite call-routing information from the customer's database (60). The customer retains ownership and control of the tandem node and its database, thereby preserving the private nature of the private network.