Dual port memory buffers and a time slot scheduler for an ATM space division switching system
AssigneeNEC Corporation
InventorMasao Akata
Life of this patent
Estimating the term…
Abstract
An asynchronous transfer mode switching network system relays packets stored in packet buffer units to output ports designated by the packets, and a time slot scheduling unit assigns time slots to the packets stored in the packet buffer units upon arrival at the packet buffer units for preventing the packets from collision in a space division switching unit, wherein each of the packet buffer units sequentially writes new packets into respective memory locations but randomly reads out the new packets in the time slots assigned by the time slot scheduling unit so that the throughput of the space division switching unit is improved.
Claims13
An asynchronous transfer mode switching network system comprising:
- (a) a plurality of input ports each supplied with a series of packets, each of said packets having a piece of port address information indicative of a destination;
- (b) a plurality of packet buffer units coupled to said input ports, respectively, each of said packet buffer units having a plurality of memory locations for storing said packets fed from the associated input port, respectively;
- (c) a plurality of output ports each serving as said designation;
- (d) a space division switching unit coupled between said packet buffer units and said output ports and providing a plurality of signal paths each coupling one of said packet buffer units and one of said output ports designated by said piece of port address information incorporated in each packet fed from said one of said packet buffer units;
- and
- (e) a time slot scheduling unit responsive to a time slot request signal fed from one of said packet buffer units upon arrival of one of said packets at said one of said packet buffer units and supplying said one of said packet buffer units with a time slot assigning signal indicative of the amount of time delay from said arrival for designating the earliest time slot where no contention of destination takes place between said one of said packets and packets fed from the other packet buffer units to said space division switching unit in said earliest time slot, in which said one of said packet buffer units supplies said one of said packets to said space division switching unit in said earliest time slot.
Dependencies are inferred from the claim text.