Abstract: An Ethernet switch with rate control and associated method is provided. Each port in the switch has individual settings of egress/ingress) rate control, which are stored in a register and configured based on required rates. The switch uses data volume that a port can output/input within each unit time to control egress/ingress rate of the port. Further, the egress rate can be precisely controlled by using uniform random numbers provided by an random number generator of the switch, and the ingress rate can be advantageously controlled by combining a proper kind of congestion control, which is performed according to the capability of a device connected to the port, such as full-duplex or half-duplex, and flow control.

Abstract: A relay control circuit that uses a hashing algorithm for increasing the hit rate in a table lookup operation. Destination medium access control (DMAC) address is extracted from a network frame. The DMAC address is scrambled to put the frequently changing bytes in a position closer to each other. The scrambled address is sent to a cyclic redundancy checking circuit, where a cyclic redundancy checking operation with hashing function capability is carried out to produce a remainder. The remainder is sent to a memory unit for a table lookup operation. Hence, the relay control circuit is capable of finding a destination port that corresponds to a given DMAC address in a very short time, thereby boosting network efficiency.

Abstract: An Ethernet switch with rate control and associated method is provided. Each port in the switch has individual settings of egress/ingress) rate control, which are stored in a register and configured based on required rates. The switch uses data volume that a port can output/input within each unit time to control egress/ingress rate of the port. Further, the egress rate can be precisely controlled by using uniform random numbers provided by an random number generator of the switch, and the ingress rate can be advantageously controlled by combining a proper kind of congestion control, which is performed according to the capability of a device connected to the port, such as full-duplex or half-duplex, and flow control.

Abstract: The present invention provides a method for congestion control and an associated switch controller. The switch controller performs either a shared memory architecture or an equal memory partition structure which limits the length of a queue corresponding to each port in response to buffer space. When exceeding a predetermined length, the queue will enter into a congested state. Preferrably, if a source port requests to establish a link in the queue, flow control is performed, and the length of the queue will be limited since there are no more packets to be received in. After escaping congestion, the switch controller returns to the shared memory architecture. Thus, the unfairness problem is improved when the network congests while network performance is enhanced.