ATM exchange system
First Claim
1. An ATM exchange system having information formatted into user cells comprising:
- a plurality of cell handlers each relating to an ATM Channel;
a plurality of buses, each bus coupled with each cell handler so that an output of each cell handler is forwarded to all the cell handlers through said plurality of buses;
each of said cell handler includinga virtual channel converter, coupled with said ATM channel, to provide an output of virtual channel identifier together with an output cell handler number of an output ATM channel to which the user cell is forward,a routing header adder, coupled with said ATM channel and an output of said virtual channel converter, said routing header adder to generate an inner cell, which has a routing header having said output cell handler number and said output virtual channel identifier generated by said virtual channel converter, and to attach said inner cell to said user cell, and said routing header adder forwarding said inner cell and user cell to a related bus,a plurality of output buffers, each buffer corresponding to one cell handler, each buffer having a) a cell pick up which picks up said inner cell and user cell which has said output cell handler number in said routing header equal to its own cell handler number and copying said output virtual channel identifier in said routing header in a virtual channel identification area of said user cell, and b) a cell buffer memory for storing said user cell from said cell pick up,a selector coupled with outputs of the plurality of output buffers for selecting a user cell,queue buffer for storing an address of said cell buffer memory which stores said user cell selected by said selector, anda cell output for outputting said user cell in said cell buffer memory based upon the address stored in said queue buffer.
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Accused Products
Abstract
An ATM (asynchronous transfer mode) exchange system for high speed packet exchange with a fixed length packet is implemented by a plurality of cell handlers (10-1 through 10-n) each related to each ATM channel, and a plurality of buses coupled with the cell handlers. An input user cell is subject to add routing information including an output cell handler number (403) and an output virtual channel identifier (404) by a virtual channel converter (12) and a routing header adder (13). The user cell which has routing information is forwarded to the bus. The cell on the bus is read out by all the cell handlers, and the particular cell handler in which the number of cell handlers coincide with the cell handler number in routing information takes the cell on the bus. In the cell handler, the cell itself read out of the bus is stored in the cell buffer memory (16), and the address of the cell buffer memory (16) of the cell is stored in the queue buffer (18). When an output channel is available, the cell is forwarded to the output channel from the cell buffer memory (16) based upon the address of the cell stored in the queue buffer (18). A plurality of queue buffers may be provided for delay time control. Congestion control is possible for loss control of a cell when an output channel is congested, based upon the number of cells waiting in the queue buffer.
106 Citations
7 Claims
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1. An ATM exchange system having information formatted into user cells comprising:
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a plurality of cell handlers each relating to an ATM Channel; a plurality of buses, each bus coupled with each cell handler so that an output of each cell handler is forwarded to all the cell handlers through said plurality of buses; each of said cell handler including a virtual channel converter, coupled with said ATM channel, to provide an output of virtual channel identifier together with an output cell handler number of an output ATM channel to which the user cell is forward, a routing header adder, coupled with said ATM channel and an output of said virtual channel converter, said routing header adder to generate an inner cell, which has a routing header having said output cell handler number and said output virtual channel identifier generated by said virtual channel converter, and to attach said inner cell to said user cell, and said routing header adder forwarding said inner cell and user cell to a related bus, a plurality of output buffers, each buffer corresponding to one cell handler, each buffer having a) a cell pick up which picks up said inner cell and user cell which has said output cell handler number in said routing header equal to its own cell handler number and copying said output virtual channel identifier in said routing header in a virtual channel identification area of said user cell, and b) a cell buffer memory for storing said user cell from said cell pick up, a selector coupled with outputs of the plurality of output buffers for selecting a user cell, queue buffer for storing an address of said cell buffer memory which stores said user cell selected by said selector, and a cell output for outputting said user cell in said cell buffer memory based upon the address stored in said queue buffer. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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Specification