摘要:
A method and system is directed to distributing a flow of packets over a network to multiple traffic management devices. An apparatus receives each packet from a network and may act as a layer 2 switch, or router, to distribute the packet to one of a group of traffic management devices. The apparatus also may receive packets from servers for which the traffic management devices are managing communications. When distributing packets, a target traffic management device is selected from the group of traffic management devices. A connection key associated with the received packet and an identifier associated with the selected traffic management device are saved such that subsequent received packets in the flow of packets are delivered to the same traffic management device.
摘要:
A memory system for ingress processing is arranged to access multiple banks in a time interleaved fashion. Each memory bank has an associated memory bank manager, which is arranged to track the contents and egress ports associated with data stored in the memory bank. Incoming data from ingress traffic is evaluated and segregated based on criteria. One of the memory banks is identified based on the criteria, and the incoming data is stored in the identified memory bank in the next available write cycle timeslot. Data constructs in the memory bank manager are updated to indicate the location and egress port associated with the stored data. The memory bank managers submit egress transmit bids to a master scheduler, which controls access to the memory banks. The memory banks are readout in interleaved fashion such that the effective average traffic arrival rate is increased and memory bandwidth requirements are reduced.
摘要:
A switching device for forwarding network traffic to a desired destination on a network, such as a telephone or computer network. The switching device includes multiple ports and uses a lookup table containing lookup keys to determine which port to forward network traffic over. The lookup tables are populated based on use. Consequently, the lookup tables on different ports contain different addresses. By storing only addresses that a port uses, each port's lookup table is unique to that port's characteristics. Additionally, aging techniques are used on both source and destination addresses in the lookup table so that stale entries are removed and memory is conserved.
摘要:
A switching device for forwarding network traffic to a desired destination on a network, such as a telephone or computer network. The switching device includes multiple ports and uses a lookup table to determine which port to forward network traffic over. The lookup table includes network addresses that are maintained in ascending or descending order. The switching device includes multiple binary search engines coupled in series including one or more precursor binary search engines and a final stage binary search engine. Together, the binary search engines perform an N iteration binary search. Additionally, a single search engine can perform multiple concurrent searches so that source and destination addresses can be obtained simultaneously and without wasted memory cycles.
摘要:
A switching device for forwarding network traffic to a desired destination on a network, such as a telephone or computer network. The switching device includes multiple ports and uses a lookup table to determine which port to forward network traffic over. The lookup table includes network addresses that are maintained in ascending or descending order. The switching device includes multiple binary search engines coupled in series including one or more precursor binary search engines and a final stage binary search engine. Together, the binary search engines perform an N iteration binary search. Additionally, a single search engine can perform multiple concurrent searches so that source and destination addresses can be obtained simultaneously and without wasted memory cycles.
摘要:
A packet switch includes a multiple of bidirectional ports that are each connected by dedicated signal paths to a multiple of memory subsystems that in turn are connected to shared memory within the switch. The signal path from each port carries a fragment of a data stream between the port and each memory subsystem. The ports send and receive data stream fragments in parallel from the memory subsystems. This parallel action reduces the bandwidth required of a memory subsystem by dividing the port's data stream among the multiple memory subsystems. In storing data for forwarding to another port, each memory subsystem selects on a time division basis in parallel the data stream fragments from the same port and stores them in memory. In retrieving data from memory for a port, each memory subsystem selects on a time division basis in parallel the same port to receive the data stream fragments read from memory. The bit width of the signal paths between the ports and memory subsystems is reduced by sending smaller, individual data stream fragments between ports and memory subsystems and sending larger, aggregate data stream fragments between memory subsystems and memory. Within each memory subsystem are modules that combine individual data stream fragments into aggregate data stream fragments for storage in memory and modules that split aggregate data stream fragments read from memory into individual data stream fragments for transmission to ports.
摘要:
A switching device for forwarding network traffic to a desired destination on a network, such as a telephone or computer network. The switching device includes multiple ports and uses a lookup table to determine which port to forward network traffic over. The lookup table includes network addresses that are maintained in ascending or descending order. The switching device includes multiple binary search engines coupled in series including one or more precursor binary search engines and a final stage binary search engine. Together, the binary search engines perform an N iteration binary search. Additionally, a single search engine can perform multiple concurrent searches so that source and destination addresses can be obtained simultaneously and without wasted memory cycles.
摘要:
A switching device for forwarding network traffic to a desired destination on a network, such as a telephone or computer network. The switching device includes multiple ports and uses a lookup table to determine which port to forward network traffic over. The lookup table includes network addresses that are maintained in ascending or descending order. The switching device includes multiple binary search engines coupled in series including one or more precursor binary search engines and a final stage binary search engine. Together, the binary search engines perform an N iteration binary search. Additionally, a single search engine can perform multiple concurrent searches so that source and destination addresses can be obtained simultaneously and without wasted memory cycles.
摘要:
In a switching device, a method of communicating data packets from sending ports to destination ports includes storing in a first stage queue packet-related data from a sending port; determining from the packet-related data which destination ports are to receive the packet-related data in the first stage queue; storing in a second stage queue associated with each determined destination port the packet-related data from the first stage queue; and using the packet-related data in the second stage queue to complete the communication of the data packet from the sending port to each determined destination port. Apparatus for practicing the method comprises a first stage queue storing packet-related data from a sending port; and a second stage queue associated with each of a set of destination ports storing the packet-related data from the first stage queue.
摘要:
Method and apparatus for detecting signal transfer errors in a digital logic system that might occur in a transfer medium between a source device and a destination device. The method includes sending a first diagnostic signal of one or more bits from the source device through the transfer medium to the destination device; comparing the first diagnostic signal received by the destination device with a second diagnostic signal within the destination device to determine if a signal transfer error has occurred; inverting the first diagnostic signal; sending the inverted first diagnostic signal from the source device through the transfer medium to the destination device; and comparing the inverted first diagnostic signal received by the destination device with the second diagnostic signal to determine if a signal transfer error has occurred. Two embodiments of the invention are disclosed. To provide near real time detection without adding signal paths, the diagnostic signals are sent along established signal paths during a diagnostic clock cycle that is added to the normal clock cycles of the digital system.