Patent ID: 7130302

Claim:
Data transmission system having a plurality of Local Area Networks (LANs) interconnected by a hub including a plurality of LAN adapters respectively connected to the LANs, the data transmission system comprising: a packet switch comprising at least a packet switch module interconnecting the plurality of LAN adapters wherein a packet transmitted by any adapter to the packet switch includes a header containing at least the address of the adapter to which the packet is forwarded, the packet switch module includes a plurality of input ports and a plurality of output ports both being respectively connected to the plurality of LAN adapters, each pair of input and output ports defining a cross point within the packet switch module, wherein the packet switch comprises a memory block for each of the cross points, the memory block including a data memory unit for storing at least a data packet and a first memory controller which determines from the header of the received data packet whether the packet is to be forwarded to the output port associated with the memory block and for storing the data packet into the data memory unit in such a case, and an output control block which includes a scheduler; the scheduler selects a memory block corresponding to the output port and causes the memory block to forward the data packet stored in the data memory unit to the output port when predetermined criteria are met and wherein the memory block includes a header validation control block for determining whether the header of a data packet received from the input port contains the address of the output port associated with the cross point, and the first memory controller stores the data packet into the data memory unit if the header contains the address of the output port and for reading the data packet to forward it to the output port.