Abstract: A flexible slotted Aloha communication protocol for a burst-type communication network divides a communication channel into a series of time cycles, with each time cycle further divided into contiguous time slices of identical duration. All data transmissions in the network begin at the start of a time slice and continue for an integer number of time slices, with the identity of the transmitting terminal, the length of the transmission and error correction, being included within the first time slice of each data transmission. Communication terminals in the network transmit reservation requests to a network hub which receives the reservation requests and reserves reserved time slots each having a number of time slices which matches the length of the data transmission to be transmitted in the reserved time slot. The reserved time slot may include time slices in more than one time cycle.

Abstract: Symbol 102 that is spread with the only short spreading code and inserted in synchronism with a long spreading code is specified by detecting the correlation with only the short spreading code. Next, another short spreading code indicative of a timing of reverse and forward link switching is specified, where the short spreading code is multiplexed at the same position as that of the detected symbol. The detection of the symbols spread with only these spreading codes enables to acquire synchronization of the long spreading code, synchronization of switching of reverse and forward links, and synchronization of a transmission frame. It is thereby possible to reduce synchronization acquisition time for the long spreading and an easy planning of base station locations without decreasing the frequency utilization efficiency.

Abstract: Service resource items (49) for use in call setup in a telephone system are held on servers (58) that are connected to a computer network which is logically distinct from the telephone system infrastructure; this computer network may, for example, make use of the Internet. Each service resource item (49) is locatable on the network at a corresponding URI and is associated with a particular telephone number. A mapping is provided between telephone numbers and the URIs of associated service resource items. When it is desired to access a service resource item (49) associated with a particular telephone number, this mapping is used to retrieve the corresponding URI (step 55) which is then used to access the desired service resource item (56, 57, 59).

Abstract: A method of dynamically, and automatically, varying the sensitivity of a receiver coupled to receive signals on a carrier medium, such as for example POTS wiring, includes the step of detecting whether more than a predetermined number of noise events, such as for example traversals of a noise threshold level, occur within a predetermined time. If the predetermined number of noise events occur, the sensitivity of the receiver is automatically varied by a predetermined increment. For example, the noise threshold level may be raised by a predetermined voltage to vary the sensitivity of the receiver.

Abstract: A method, apparatus and article of manufacture for routing a data packet in a fault tolerant manner. A data packet is received from an incoming data channel and is transferred to a switching engine (SE) through an access processor engine (APE). A route for the data packet is generated using a central processor resource (CPR). The data packet is transferred from the SE to an outgoing trunk physical module (TP) using the route.

Abstract: A queuing system (230) stores a package (246) derived from an ATM cell, the package including an internal interface header (IIH) and either an ATM cell payload or an AAL2 packet. The queuing system comprises a queue (312, 320) for storing the package, as well as a processor which executes plural functions. A time stamping function applies a time stamp upon storage of the package in the queue. The time stamping function can apply the time stamp to a package as replacement of the internal interface header. A time stamp checking function uses the time stamp to make a determination whether the tenure of the package in the queue is longer than permissible. The time stamp checking function can make the tenure determination in conjunction with a potential readout of the package from the queue. Alternatively, time stamp checking function can make the tenure determination when invoked by a queue monitoring function which monitors a fill level of the queue (e.g., when a queue fill level exceeds a threshold).

Abstract: Preventing transmission loops in a ring network that utilizes label switching involves generating right side and left side ring packets from an ingress packet and setting right and left TTL values for the packets that prevent the packets from traveling on the same transmission link. Setting the right and left TTL values of the ring packets to values that prevent the packets from traveling on the same link transforms the physical topology of the ring into a logical arc. In an embodiment, the logical arc established by a network node can be dynamically rotated in response to various network conditions to avoid packet transmissions on a particular link of the ring network.

Abstract: A terminal with a shaper comprising an ABR bandwidth calculator for calculating a shaping bandwidth from congestion notification information in each received RM cell and a bandwidth allocator for calculating bandwidths allocated between respective connections with the bandwidths given priorities, wherein cells are transmitted with one small in value, of the result of calculation by the ABR bandwidth calculator and the result of calculation by the bandwidth allocator as a shaping bandwidth. With respect to connections subjected to a limitation of each shaping bandwidth by the congestion notification information, the priority for bandwidth allocation is lowered so that the bandwidths unavailable to the connections are deallocated to other connections.

Abstract: The present invention describes a method and apparatus for reducing EMI emission in a multi source electronic system. The phase of the modulated waveform is varied to minimize the number of clocks within the EMI measurement bandwidth. The phase of the modulated waveform is varied in proportion to the number of EMI generating sources in the electronic system. The spread-spectrum clock is used as reference for phase delay of the modulated waveform. The phase delay can be predetermined or dynamically programmed according to the number of the EMI sources in the electronic system.

Abstract: A method, apparatus and article of manufacture for prioritization of control plane traffic in a router. A destination slot is allocated in a sliding window buffer via a control channel. A data packet is received via a data channel. An acknowledgement that the data packet was received is sent via the control channel. The destination slot is released via the control channel.

Abstract: In a multiplexer, a channel selection controller determines which channel code is to be selected for a control data generator, each of multiplex buffers, and null packet generator, a PTS/DTS controller replaces PTS with DTS in a program being multiplexed, an output controller reads and deliver TS at a time synchronous with a system clock, and a virtual decoder buffer simulates each of T-STD buffers as in MPEG2.

Abstract: A format programmable hardware packetizer (110) receives real-time raw input data (125) from a multimedia data source (103) via an analog to digital converter (105) and a data encoder (120) gated by encoder interrupts (127). The real-time raw input data is buffered in an internal byte collector of the packetizer (110). A main CPU interrupt (117) is issued to the main processor (130) when a packet boundary code is received. The packetizer (110) formats the data according to a desired format selected on line (115) for dump to the main memory (140) while providing a managed, much lower level of interrupts to the main processor (130) on the CPU interrupt line (117). A plurality of hardware packetizers (110) can be deployed according to alternative constructions for efficient real time packetizing in various selected formats.

Abstract: A method is shown for splitting a static pool of Internet Protocol (IP) addresses in a Remote Access Server (RAS) of a network server device into a dynamically assignable pool and a fixed assignment pool. The IP addresses of the dynamically assignable pool are available to any remote client connecting to the network server. The IP fixed assignment pool contains IP addresses that have a predetermined assignment to specific remote clients. When a remote client connects to the network server, it requests assignment of an IP address from the RAS. If the remote client does not specify an IP address in its IP address request, then an IP address from the dynamically assignable pool is assigned to the remote client for the duration of its connection to the network server. If the remote client does specify an IP address in its IP address request, then the fixed assignment pool is searched for the requested IP address and the address is assigned to the remote client.

Abstract: A novel crossbar switching matrix that improves the transmission of variable length broadcast packets by greatly reducing transmission latency time. Unicast traffic is halted in the middle of packet transmission operations and the broadcast packet is transmitted. Once the broadcast packet has finished transmission, unicast packet transmission resumes without any loss of data. A unicast buffer is used to store the unicast packet while the broadcast packet is being transmitted. A broadcast buffer is used to buffer the broadcast packet as it egresses from the switch matrix. In this fashion, the broadcast information is given high priority and passes quickly through the switch without the large delays associated with the prior art switch matrixes. The crossbar switch matrix of the present invention is applicable to any switching matrix adapted to switch variable length data units.

Abstract: Digital data signals at a variable input frequency are converted by a numerically controlled oscillator and an interpolator to a signal at a fixed output sampling frequency. The conversion of the variable input frequency to the fixed output sampling frequency may be by a factor other than an integer. The interpolated digital data signals at the fixed output sampling frequency are then modulated into a pair of trigonometric signals at a programmable carrier frequency, one signal having a cosine function and the other signal having a sine function. The modulated signals at the fixed output sampling frequency are then combined to create a modulated signal at a carrier frequency determined by the frequency of the sine and cosine signals. The modulated signal is sampled at the fixed output sampling frequency and converted to a corresponding analog signal using a digital-to-analog converter.

Abstract: A circuit which synchronizes the phase of a data stream from a transmitting system, to the phase of the clock signal of the receiving system. Two frames of data from the transmitting data stream are stored in a memory which is continuously updated as the data for each time slot is stored in a different word of memory. The storage of the incoming stream data is controlled by the clock signal from the transmitting system. The data stored in the memory is then read out of that memory under control of the clock signal from the receiving system. As each word is read out, it is reinserted into the bit stream that is transmitted to the receiving system. An address control circuit ensures that write addresses have priority over read addresses. Similarly, a read/write control circuit ensures that write signals have priority over read signals. The read signals are arranged such that two read signals are available for each time slot.

Abstract: A technique for compensating for frequency distortion in a band-limited communication channel, using a random-access memory (RAM) to store successive samples of a signal pulse, the samples having been precalculated to perform an equalization function prior to transmission of the pulse. The signal samples are retrieved, converted to analog form, and filtered to produce a precompensated analog pulse signal. In one embodiment of the invention, equalized profiles of a limited number of pulses of different shapes are stored in the RAM, and are retrieved as needed for transmittal through the band-limited channel. Thus the invention can perform its equalization function while facilitating encoding of the signal into a different form, such as modified duobinary code.