摘要:
A method for easing data transmission congestion in a switch device having a plurality of ports. The switch device includes a shared buffer capable of dividing into a plurality of buffering units. The method comprises the steps as follows. A plurality of output queues are provided, in which the output queues have a one-to-one correspondence with the ports, and each output queue has a number of reserved buffering units. The buffering unit(s) are then assigned in the shared buffer. A packet is received from a source port and storing the packet in an assigned buffering unit. The target port of a packet is determined according to a header of the packet. Then, the buffering unit containing the packet is linked to the output queue that corresponds to the target port. The free buffering units are thus controlled according to a number of reserved buffering units in the output queue and a triggering or a terminating condition of the source port.
摘要:
A output queuing method for forwarding the packets sequentially in a switching network. Each port is related to a port output queue and a global output queue is shared by all port output queues. A FIFO (First In First Out) block is allocated into each port output queue and the global output queue. The FIFO block contains a number of FIFO nodes. Based on the type and destination ports of the received packet, the fields of the related FIFO node in the port output queue and the global output queue are set. The packets are sent out or skipped based on the related fields.
摘要:
A method for performing a MAC address lookup in a network switch of an Ethernet network is provided, using a memory structure including a number of multi-slot buckets. Each of the multi-slot buckets is mapped to a hash key derived from a MAC Address. Each of the multi-slot buckets has a number of forwarding table section, each storing a number of the forwarding table entries. If two forwarding table entries are stored in each forwarding table section of a 4-slot bucket ¼ memory space and ½ access time can be saved. Thus, the lookup for the forwarding table according to the MAC address in the Ethernet switch IC can be effectively performed.
摘要:
An inflatable headband comprising an elongated, strap-like air-bag body covered with a layer of velvet or cotton cloth, having a pair of connecting elements at two opposite ends, a plurality of ring holes made through said air-bag body by the process of heating and sealing or embossed stripes formed on said air-bag body by the process of heat pressing, a pair of spaced eye bars extending from the side edge thereof, and at least one air valve. The air-bag body is inflated and then fastened around the head by the pair of connecting elements. Ornamental items are fastened in the ring holes to make the structure more attractive. The two spaced eye-bars are provided for holding user's eyeglass on the head.
摘要:
A method for compensating for clock signal difference between a switch and peripheral device, including a receiving process and a transmitting process. For the receiving process, after an N-th packet is received, a first counter is triggered and begins to count. When an (N+1)-th packet is inputted, the counter stops counting and then an inter-packet gap IPG(N, N+1) between the N-th packet and the (N+1)-th packet is recorded into the N+1 queue link node QLN(N+1) according a counting value by the first counter; otherwise, the first counter keeps counting. For the transmitting process, after an inter-packet gap IPG(M−1, M) is obtained, and the M-th packet is transmitted, and then the second counter is triggered to begin to count. When a counted value by the second counter is equal to the clock cycle value corresponding to the inter-packet gap IPG(M−1, M), the second counter stops counting. When an inter-packet gap IPG(M, M+1) is obtained, and the (M+1)-th packet is then transmitted; otherwise, the second counter keeps counting.
摘要:
A switch controller using a congestion control method can relieve congestion in a network. The Ethernet switch controller has the capacity to select a suitable congestion control mode according to each connection port and state of the connected device. If a flow control mode is selected, the switch controller issues a flow control frame and waits for the passing of a guard period roughly equivalent to a period of about inputting three packets. If the connected device continues to transmit network packets after the guard period, the switch controller switches from the flow control mode to a drop control mode. Hence, the received packets are discarded and congestion is prevented. Consequently, the switch controller of this invention can still carry out congestion control operation when the switch controller is connected to a device having no standard flow control capability.
摘要:
A method and system is provided for use on a switching hub in a packet-switching network for handling the output queuing of received packets in the switching hub to be more efficient and cost-effective. This method and system is characterized in the provision of a broadcast output queue in addition to the output queues at the ports of the switching hub, with the broadcast output queue being exclusively used for sequencing broadcast packets and the output queues being used exclusively for sequencing unicast packets. When a broadcast packet is received, the method and system assigns a free-list link node to the broadcast output queue, but not to the output queues, and meanwhile adds one to the broadcast count in each of the last link node in each of the output queues. When a certain port completes the outputting of all associated unicast packets, it is checked whether the broadcast count in the last link node in each output queue is zero or nonzero; if nonzero, the switching hub then outputs every broadcast packet indicated by the broadcast count. The disclosed method and system not only allows a reduced number of memory accesses as compared to the prior art but also requires a low memory capacity to implement, and therefore is more efficient in operation and more cost-effective to implement than the prior art.