Abstract: A method for recovering from a sun transit in a communication of a very small aperture terminal (VSAT) is disclosed, in which the sun transit outrage (STO) is prevented by using a sun transit recovering algorithm, thereby making it possible to apply the very small aperture terminal (VSAT) to the satellite communication. Generally, the communication system of the very small aperture terminal (VSAT) in which a still track satellite is used includes a VSAT central station (VCS), a network management system (NMS), and a VSAT remote station (VRS). In this communication system, when the sun reaches near the boresight axis of an antenna, an STO phenomenon occurs, with the result that the communication system is influenced by the additional noise power of the sun. Consequently, the reliability of the communication system drops to below an average quality which is tolerable in an antenna communication system.

Abstract: An internetworking node for providing internetworking services for mobile wireless nodes is disclosed. Each mobile wireless node is associated with at the most one internetworking node. Each mobile wireless node selects which internetworking node it will associate with. The internetworking node will then act for all wireless nodes associated to it in relaying messages between wireless nodes or between a wired LAN and the wireless nodes. A tracking mechanism for such a system which maintains a table of all the internetworking nodes the wireless node has recently heard and deleting all such internetworking nodes which have not been heard recently is disclosed. A switching mechanism for such a system for determining when the wireless mobile node should switch its association from one internetworking node to another is also disclosed.

Abstract: In an extended overall radio communications network, one or more dedicated Network Interface Modules (NIMs) are provided in each multisite trunked communications systems to permit the interconnection and communication between plural, multisite systems. A remote multisite system appears through the local NIM as just another site interface to the local multisite system. Basic and advanced dispatch console functions are effected over the extended network via the NIMs in a manner that is transparent to the console operator.

Abstract: A packet filter can be programmed by a remote controller to detect packets meeting a particular criterion and to report detection of these packets to the controller. The reports from the packet filter are collected and analyzed by the remote controller. A streams module that incorporates the packet filter is used within a Solaris operating system environment that has been enhanced to support an object framework. The streams module exports a programming interface to the packet filter defined in an interface definition language (IDL). The streams module can be pushed onto a network device in a similar fashion to other streams modules. The streams module responds to requests from one remote controller or to requests from more than one remote controller. These remote controller requests arrive as remote procedure call (RPC) requests on the IDL object references exported by the module.

Abstract: A variety of methods of coordinating communications between a plurality of remote units and a central unit to facilitate communications using a frame based discrete multi-tone (DMT) transmission scheme am disclosed. In one aspect of the invention, synchronized quiet times are periodically provided in the upstream communication stream. The synchronized quiet times are used to handle a variety of control type functions such as synchronization of new remote units, transmission channel quality checking and handling data transfer requests. The information received is used to facilitate the dynamic allocation of bandwidth during use. In another aspect, a data request signal may be used to indicate either a desire to transmit at a particular data rate or a desire to transmit a particular amount of information. In the former case, the central unit allocates sufficient sub-channels to the remote unit to facilitate transmission at a requested data rate that is specified in the data request information.

Abstract: A system for noise canceling using a single return conductor. The system employs a first unit, a full duplex communications path coupled to the first unit, and a second unit coupled to the first unit via the full duplex communications path. The full duplex communications path employs at least three conductors: a forward signal carrying conductor; a reverse signal carrying conductor; and a single return conductor. In order to perform noise canceling, the first unit may employ, for example, a first adder coupled to the reverse signal carrying conductor, and a first canceling impedance coupled between the single return conductor and a first unit ground. Similarly, the second unit 12 may employ a second adder coupled to the forward signal carrying conductor, and a second canceling impedance coupled between the single return conductor and a second unit ground.

Abstract: A method for improved data communications in a wireless system is described. An enhanced access burst is provided having an additional logical information field, or alternately using one of a set of possible synch sequences indicative of supplementary information. Upon receipt of a system parameter indicating an enhanced access burst capability, the communication unit sends an appropriate enhanced access burst with the increased information. A reduction in system messaging is thus achieved, e.g., by avoiding the need to send the supplemental information via subsequent bursts.

Abstract: A method for allocating timeslots to mobile stations in a cell in a cellular communication system is disclosed. First, the distance each mobile station is from a base station in the cell is determined. Then each mobile station is assigned a timeslot based upon the distance each mobile station is from the base station, wherein the timeslots within a contiguous group of timeslots are assigned to the mobile stations in the order of the mobile stations increasing distance from the base station and at least one timeslot at the back of the contiguous group is not assigned so as to allow bursts from the mobile stations to slide into the next timeslot.

Abstract: The application describes a network comprising transceivers (1..6) linked in a network topology. The positions of the transceivers in the network topology are changed in dependence on the loads on the end-to-end connections (VC1..VC5) between the transceivers in the network. A configuration is chosen to give efficient use of the capacity available in the network. Each time that a new end-to-end connection (VC) within the network is set up the positions of the transceivers (1..6) are changed such that the network remains optimized.

Abstract: In an ATM-LAN communication system, cell assembly disassembly (CLAD) units provide segmentation of a packet received from a LAN into payloads and assembling them into ATM cells, and disassembling received ATM cells into payloads and assembling them into a packet for transmission to the LAN. A connectionless switching function (CLSF) processor receives ATM cells either from an ATM switch and the CLAD units, and includes a database for storing address information of the received ATM cells and rotating the received ATM cells to the ATM switch and the CLAD units according to the address information of the database. The database has a destination address (DA) field, a VPI field and a VCI field.

Abstract: An method for improved transaction reservation in an Integrated Satellite Business Network. The method includes generating a transaction request message indicating the number of slots needed to transmit a data message. Then, the method includes transmitting the transaction request message to a host terminal, and assigning one or more slots within an inroute to the remote terminal. The method then includes transmitting a transaction assignment message containing the number of slots assigned and which slots were assigned. In response to this assignment, the method includes transmitting at least a portion of the data message during the slots assigned.

Abstract: In a ring type ATM network system employing an ATM cell transmission mode, two paths are provided to correspond to a dual ring between node equipments, one path is selected to transmit a cell, and the other path is defined as a stand-by system. The path is selected for each combination of the node equipments, and is switched over to the stand-by system when a malfunction is caused. In order to configure a path for multicast, a multicast cell is not relayed between specific adjacent node equipments, thereby logically regarding the two rings as two buses. It is thereby possible to select a path having a smaller number of passing node equipments in a normal state, and reduce a transmission delay. During reconfiguration of a path at a time of occurrence of the malfunction in the ring or the node equipment, it is possible to reduce the transmission delay between optional node equipments to a delay less than a time required for one cycle of the ring, and to implement multicast transmission of the cell.

Abstract: A method for reliability-controlled data detection of TDMA data bursts with a central test sequence for determining the identification parameters of the transmission channel, wherein: the data segments adjoining the test sequence at both ends are subdivided into N sectors A.sub.i, i=.+-.1, . . . ,.+-.N, with M sampled signal values each; in the kth processing step the sectors A.sub.1+, +1.ltoreq.i.sup.+ .ltoreq.=N are detected, suitable measures .LAMBDA..sub.i- and .LAMBDA..sub.i+ are determined for the detection results, and the detection result of the sector whose measure of reliability has the smaller value is rejected again if by then all sectors A.sub.-1, . . . , A.sub.i-+1 and A.sub.+1, . . . , A.sub.i+-1 have finally been processed; in the kth processing step the sector A.sub.i- is detected if -N<i.sup.- .ltoreq..sup.- 1 and all the sectors A.sub.i+, +1.ltoreq.i.sup.+ .ltoreq.+N have already been processed; in the kth processing step the sector A.sub.i+ is detected if +1.ltoreq.i.sup.

Abstract: An explicit rate indication method for congestion management in computer and telecommunication networks. Sources monitor their load and provide the information periodically to switches. The switches, in turn, compute the load level and ask the sources to adjust their rates up or down. The scheme achieves high link utilization, fair allocation of rates among contending sources and provides quick convergence.

Abstract: The method and system for enhanced efficiency in a multisession communication system which utilizes a series of data packets wherein each data packet includes an indication of the identity of a particular session to which that data packet belongs. Each received data packet is examined as that data packet is received to determine a session identity for that packet. An indication of the session identity is thereafter listed within a session queue only in response to an initial occurrence of that session identity. Each data packet for a listed session identity is then stored in a data packet queue in First-In First-Out (FIFO) order which is associated with the listed session identity wherein all packets for a session remain in order, even though the overall order of all packets may be enhanced.

Abstract: The asynchronous transfer mode (ATM) interface, which may be a segmentation and reassembly unit, controls segmentation of packets into cells and reassembly of cells into packets for interconnecting a computer system to an ATM system. An architecture is disclosed which partitions load and unload functions within the ATM interface. The load and unload functions are separately partitioned for segmentation and for reassembly. For segmentation, a transmit load engine controls storage of data from packets into an external buffer memory; whereas transmit unload engine handles extracting data from the memory, segmenting the data into cells, and transmitting the cells to the ATM system. For reassembly, a receive load engine handles receiving and storing the cells corresponding to the packets into a memory; whereas a receive unload engine controls extraction of the data from the memory and transmission of the packets to the computer system.

Abstract: A network data stream synchronization method and system are disclosed. Operating delay and loss parameters are accepted and a data stream buffer is initialized. The network delay experienced by a data packet is determined and a buffer delay is imposed to provide a fixed end-to-end delay. Packets arriving too late to be played within the fixed end-to-end delay are discarded. Network delay models may be updated and clock drifts may be detected and compensated for using historical buffer data.

Abstract: A system of the invention connects an Asynchronous Transfer Mode (ATM) data network to a plurality of host units. The data network transfers data in the form of ATM cells. A plurality of ATM termination units are connected between the network and the host units respectively. Each termination unit includes a virtual channel memory for storing ATM cells; a processor for segmenting and reassembling the ATM cells stored in the memory; a network interface for transferring ATM cells including segmented Conversion Sublayer Payload Data Units (CS-PDU)s between the memory, the processor and an ATM network; and a host interface for transferring unsegmented CS-PDUs between the memory, the processor and a host unit. The processor of each termination unit includes a computing unit, and a programmable instruction memory for storing a program for controlling the computing unit.

Abstract: A communication system is provided which permits the transfer of broadband multimedia data through a network. The system includes network terminals, a transmission backbone, and a call set-up server. The call set-up server controls call handling and connection handling. The call set-up server includes an access part, a user part, and a central part. The central part sets up a call between parties in the system and operates independently from the access part and the user part. The call set-up server also includes a service pointer which permits supplementary services to be added, removed or modified and permits access parts to be added or modified, without affecting already existing services and access parts.

Abstract: A multiple access communications system reuses a set of N carrier frequencies in adjacent communications sites to provide more than N minimally cross-correlated frequency-hopping communications channels. A first set of communications channels is associated with a first of the communications sites. No two of the channels in the first set employ the same frequency at the same time. A second set of communications channels is associated with a second of the adjacent communications sites. No two of the channels in the second set of channels employ the same one of the N carrier frequencies at the same time. One or more sets of the minimally cross-correlated channels are further defined so that none of the channels in such sets employ the same frequency at the same time as more than a predetermined number of the channels in another of the sets of the minimally cross-correlated frequency-hopping communications channels.