摘要:
The packet switch performs a scheduling process by selecting a unicast packet or a multicast packet to be output from each of N input buffers such that input lines and output lines cannot conflict each other for a unicast packet, and such that the input lines cannot conflict each other for the multicast packet.
摘要:
An input line interface device that is used to accommodate packets from a high-speed line efficiently and to reduce a processing load on a back stage caused by routing control. A packet allotting section divides a variable-length packet, allots divided packets to parallel lines, and outputs the packets. A flow group classifying section classifies the packets into flow groups on each of the parallel lines. A sequence number giving section gives the packets sequence numbers corresponding to or independent of the flow groups. A buffering section stores the packets to which the sequence numbers have been given in a buffer or reads out them from the buffer to exercise sequence control over the packets in the flow groups. A flow separating switch separates the packets according to the flow groups and outputs the packets.
摘要:
A scheduling system is capable of causing no deterioration of characteristics even under equal and unequal loads, eliminating the necessity for high-speed repetitive scheduling and complicated arithmetic processes, simplifying its architecture and having its processing speed which does not depend upon a device capability. For attaining this system, an inter-highway pointer is updated to an adjacent line (rightward) when the scheduling for all the lines are finished. If the inter-highway pointer is updated N-times in the same direction (clockwise), the same pointer is updated to an adjacent line in a reverse direction (counterclockwise) in next N-processes of scheduling.
摘要:
To achieve QoS control, drop control and multicast control of a variable-length packet at high speed in small scale hardware, a packet divider divides a variable-length packet into fixed-length packets, and an input buffer section stores the divided fixed-length packets into queues by output lines and by QoS classes. A large number of QoS classes are mapped into only two kinds of classes including a guaranteed bandwidth class for which an assigned bandwidth is guaranteed and a best effort class for which a surplus bandwidth is allocated, thereby to achieve scheduling at the input side by an inter-line scheduler. An output buffer section assembles a variable-length packet from fixed-length packets that have been obtained by switching at a switch section in an output buffer section. A QoS control is performed based on a packet length.
摘要:
A packet switch includes an input buffer memory unit having a logic queue corresponding to an output line, a control module for a first pointer indicating a scheduling start input line, a control module for a second pointer indicating a scheduling start output line of scheduling target outlines, a request management control module for retaining transmission request data about a desired output line, a scheduling processing module for starting a retrieval from within plural pieces of transmission request data from the output line indicated by the second pointer, and selecting an output line that is not ensured by other input lines, a packet buffer memory unit for temporarily storing a plurality of fixed-length packets and sequentially outputting the fixed-length packets, a switch unit for switching the fixed-length packets outputted from the packet buffer memory unit, and an address management unit for segmenting an address of the packet buffer memory unit into fixed-length blocks for a plurality of packets, and managing the address on a block basis. With this construction, the memory address is managed on the block basis, and a memory capacity can be reduced by giving an intra-block individual address per queue when in writing or reading.
摘要:
A packet switch device having a plurality of input buffers; a packet switch; a plurality of schedulers, having a pipeline scheduling process module wherein a plurality of time units corresponding to the number of output lines is spent in scheduled sending process of the fixed length packets from the input buffer, and wherein the scheduled sending process is executed in a number of processes, in parallel, the number of processes corresponding to the number of the input lines, having a sending status management module wherein sending status of the fixed length packets which constitute one frame is managed for each of the input lines, and provided corresponding to any of the output lines; and at least one result notification module for notifying the input buffer of result information from the scheduled sending process performed by each of the plurality of schedulers. Further, in the scheduled sending process executed in a number of processes, in parallel, the device does not select the input line sending the fixed length packets corresponding to the same frame, and, after determining a selection, the device maintains the selection of the same input line until the completion of sending the fixed length packets corresponding to the same frame.
摘要:
The invention relates to a bandwidth control apparatus in ATM equipment, for inserting management cells such as OAM cells, the control apparatus being configured to secure a bandwidth for the insertion of a management cell such as an OAM cell when the need arises, while guaranteeing the service quality of user cells, thereby making effective use of network resources for a best effort service such as ABR or UBR. The bandwidth control apparatus comprises a cell insertion block 1-10 for inserting a management cell such as an OAM cell and a shaping block 1-20 for performing user cell shaping, wherein the cell insertion block 1-10 issues an empty cell request when a cell insertion request occurs, the shaping block 1-20, upon receiving the empty cell insertion request, inserts an empty cell in a user cell stream being output from a shaping buffer 1-22, and the cell insertion block 1-10 writes a management cell such as an OAM cell over the empty cell inserted on a cell highway 1-30, thus sending the management cell out on the cell highway 1-30.
摘要:
A packet switch which can cyclically use α scheduling process results to determine one of M output lines as a destination of a packet stored in each of N input buffer sections by α scheduler sections independently performing scheduling processes is disclosed.
摘要:
Packets input from input HWs #0 to #3 to a packet switch device are buried in time slots A through D. The packet switch device alternately switches the input packets in units of time slots, and inputs the packets to two 4×4 switches. The 4×4 switches make normal switching, and distribute the packets to respective output ports. Then, the packets output from the two 4×4 switches after being switched are alternately multiplexed, and output to output HWs #0 through #3. By making switching in units of packets as described above, a process overhead is prevented from being increased, and also expansion can be easily made. Besides, hardware scale can be made small.
摘要:
A plurality of switching modules arrayed in a plurality of columns and in at least one row switch over paths in accordance with path data contained in cells to transfer inputted data to a target line on the cell-unit. One or more path switching units are provided between two adjacent columns of switching modules among plural columns of switching modules and switch paths between the respective switching modules, disposed in a side-by-side relationship in a row direction, of one column of switching modules of the two adjacent columns of switching modules and the respective switching modules, disposed in the side-by-side relationship in the row direction, of the other column of the two adjacent columns of switching modules.