摘要:
An ATM switching system includes PVC allocation circuits 13-i corresponding to output queues 14-i is disclosed. At the time of arrival of the leading cell of each burst data, if the output line has a room, the PVC of the burst data is stored as information for admission and identification. The subsequently-arriving cells having the same PVC identification information as the stored identification information are nullinput to an output buffer, and the cells of the remaining burst data are all discarded. Even when a plurality of burst data compete for the same output line, the fact that all the cells other than the first-arriving admitted burst data are discarded prevents the cells from being input other than within a predetermined bandwidth and localizes the burst data affected by the cell discarding due to output queue overflow.
摘要:
The present invention involves a system and method for classifying information received by a communications device. A first parameter having a first parameter range and a second parameter range, and a second parameter having a third parameter range and a fourth parameter range, are defined. A first class having one of the first parameter and the second parameter ranges, and one of the third and the fourth parameter ranges, are also defined. A second class having another one of the first parameter and the second parameter ranges, and another one of the third and the fourth parameter ranges, is also defined. Information having a first parameter value and a second parameter value is received. The method determines if the first parameter value is within one of the first and second parameter ranges and if the second parameter value is within one of the third and fourth parameter ranges is made. If so, the information is classified into one of the first and second classes based on the first parameter value and the second parameter value, otherwise the information is classified as a default class. An output value representative of the classification is then generated.
摘要:
This invention provides a network management equipment and a packet switching equipment which eliminate a connection setup delay time, reduce a delay and a delay variation involved in data transfer, and effectively perform connectionless data flow processing in a large data network. The network is divided into a connection-oriented core network and a plurality of connectionless access networks connected to the core network where a plurality of connections (called permanent virtual route (PVR)) are set up among a plurality of edge nodes. The network management equipment selects one route from a plurality of PVRs for connectionless data flow received from one of the access networks and transfers data along the PVR.
摘要:
An ATM hub transcoder system (AXC) is coupled to a base station controller (BSC), a mobile switching center (MSC), and a base transceiver subsystem (BTS). In one embodiment, the transcoder system is comprised of an ATM switch subsystem, a transcoder subsystem (XC), a base transceiver subsystem interface (BTSI), and a mobile switching center network interface subsystem (MSC-NI). The ATM switch provides coupling and communication of data in an internal ATM format between each of the XC, BTSI, MSC-NI, and BSC, responsive to control signals from the BSC. The MSC-NI provides for conversion of the format of the data between the internal ATM format and a synchronous format. In one embodiment, the synchronous format is used for communication between the MSC and the NI, responsive to the MSC and the BSC, and the BTSI provides for communicating mobile subsystem information between the BTS and the XC, responsive to the BTS and the BSC. In one embodiment, the interface between the ATM switch and the MSC-NI is PCM encoded in the internal ATM format data. The In an alternate embodiment, the interface between the ATM switch and the BTSI is of digitally encoded voice data in the internal ATM format. The MSC-NI couples the data originating from the MSC via the ATM switch to the transcoder subsystem (XC).
摘要:
Set-top terminals utilized in broadband broadcast networks are becoming increasingly intelligent (programmable). However, transmitting executable code, data and interactive audio/video materials through a selectively dedicated link requires an extensive, broadband point-to-point broadband network, which is prohibitively expensive to implement for large numbers of customers. The present invention provides for downloading application software and transmitting audio/video information through one channel of a digital broadcast network. The network also provides two-way, low-speed data communications capacity, e.g. for signaling and/or interactive text services. Signaling via data communication with a text server controls downloading of executable code from the digital broadcast channel into a programmable digital set-top terminal. Execution of the downloaded code in turn controls selective capture and presentation of audio and video segments received over one of the digital broadcast channels. Resident operating system and application software in the terminal provides all communication with nodes of the network. The downloaded code forms a non-resident application having a set of predetermined function calls for activating communication functions of the resident software.
摘要:
A mechanism by which interrupt frequency mitigation is combined with transmit raw cell status report frequency mitigation is presented. A tx raw cell status report is allowed to occur for only every N raw cell tx slots consumed. When the rate of interrupt requests is mitigated in accordance with holdoff parameters including a holdoff event count corresponding to X interrupt events and a holdoff time interval, and the raw cell status report counts as an interrupt event, an interrupt request is generated for an enabled interrupt if N*X events has occurred or the holdoff time interval has elapsed.
摘要:
In an asynchronous transfer mode (ATM) cell transfer apparatus, a valid cell detecting circuit determines whether or not each of ATM cells is valid, based on a specific data of the ATM cell. When it is determined that the ATM cell is not valid, the valid cell detecting circuit discards the ATM cell. On the other hand, when it is determined that the ATM cell is valid, the valid cell detecting circuit writes the ATM cell in a buffer circuit. A read control circuit reads out the ATM cell from the buffer circuit.
摘要:
A mechanism for avoiding the initiation of control read transactions on a system bus coupling a host system having a host memory and an interface connected to a peripheral unit as data is moved between the host system and the peripheral unit is presented. Control information associated with data memory portions in host memory is written to the interface for data memory portions storing outgoing data and data memory portions to receive incoming data. The interface includes a controller for moving data between the host memory and the interface by first obtaining the control information for the associated data portions. The interface writes status reports in association with the movement of data between the interface and the host memory via the system bus. The mechanism thus enables data transfers to occur via the system without the initiation of control reads in absence of an exception condition.
摘要:
A number of storage units and a number of state machines are provided to reorder interleaved ATM data cells for a number of channels incoming to a networked host computer. The storage units store the incoming ATM data cells, a number of data structures tracking the stored ATM data cells for the channels and the free resources, and an unload schedule queue. The state machines load and unload the incoming ATM data cells, and update the tracking data structures and schedule queue accordingly.
摘要:
A packet based data transmission system includes a flexible optimized nonocking transmit interface that incorporates optimized buffer modes, dynamic and static chaining, streaming and the utilization of small packet formats. Static chaining refers to connecting together the linked list for successive packets for the same transmit channel or virtual channel. Dynamic chaining refers to means by which the network interface performs this chaining automatically, thereby solving a blocking problem. On the transmit side, streaming refers to initiating the transmission of packet data before the entire packet data has been presented to the interface. This, in turn, permits more rapid recycling of the buffer space. On the receive side, streaming refers to initiating the processing of packet data before the entire packet has been received. The packet transmission system also includes a receive interface that incorporates a chunking system in which a buffer is divided into multiple chunks or segments to accommodate different size packets. Additionally, the receive interface includes an optimized linked list scheme to support chunking in which no linking element is required for the first buffer in the linked list. In one embodiment a small packet format is provided to reduce the relative overhead in sending small packets. In another embodiment the optimized buffer mode associated with the receive side can be utilized on the transmit interface for further reducing overhead.