Abstract: A method for transmitting data between line cards in a distributed network switching system, through a switch fabric which is separated from said line cards, said method comprising receiving at said switch fabric information regarding queues of data packets that have arrived at said line cards and are waiting to be transmitted therefrom, recording said information at one or more databases located in said switch fabric, computing in said switch fabric a suitable array of connections between said line cards according to the information recorded at said one or more databases, providing instructions to said line cards regarding the data that is allowed to be transmitted therefrom, establishing a physical array of connections in said switch fabric to allow said transmission, and updating said one or more databases at said switch fabric accordingly, wherein said updating of the one or more databases occurs before said transmission of data from the input line cards takes place, such that the updated information stor

Abstract: In a method and system for scheduling unicast and multicast data packets associated a weight value reflecting the urgency of each queue in a set of available input nodes to transmit its queued cells is computed. If the highest weight queue in each input node is unicast, a request containing the weight of the queue is sent to a single output node relating to the highest weight queue. Otherwise, a request containing the weight of the queue is sent to one or more output nodes relating to the multicast queue. A grant is sent to the highest weight input node sending a request for a specific output node. Input nodes relating to unicast queues are removed from consideration in successive iterations. Input nodes relating to multicast queues may compete in successive iterations but only from the same multicast queue.