Abstract: A switch is configured to block packets from being transmitted through designated ports. The switch has port bitmap generator configured to obtain a port bitmap and a table is configured to store a block mask indicating which port the packet should not be transmitted. A block mask lookup is configured to determine the block mask for the packet from the table, and a transmit port bitmap generator is configured to determine which ports the packet should be transmitted using the port bitmap and the block mask.

Abstract: A network device for implementing VLAN translation on a packet. The network device includes a user network interface port for receiving and transmitting packets to customers of a network. The network device also includes a network to network interface port for communicating with a second network device in the network. A packet received at the user network interface port is classified, translated based on a predefined provider field associated with the packet, and encapsulated with a tag that is removed when the packet is transmitted from the user network interface port to a customer.

Abstract: A network device that processes packets and includes at least one legacy component for performing basic processing on packets in the network device. The network device further includes at least one advanced component for performing advanced processing, which can not be performed by the legacy component, on packets in the network device. When an incoming packet to the legacy component requires advanced processing, the legacy component performs the basic processing and transmits the packet to a loop-back port on advanced component. Upon receiving the packet, basic processing is disabled on the advanced component and advanced processing is performed on the packet.

Abstract: A method of adjusting fields of a datagram in the handling of the datagram in a network device may comprising receiving a datagram, with the datagram having at least module identifier fields and port identifier fields, at a port of a network device, adding or subtracting an offset value to at least one of the module identifier fields and at least one of the port identifier fields of the datagram based on data registers in the network device, and forwarding the datagram to a legacy device based on the module and port identifier fields of the datagram. A size of each of the module identifier fields and the port identifier fields handled by the legacy device may be smaller than a size of the module identifier fields and port identifier fields handled by the network device.

Abstract: Methods and systems for processing packets in data network using multistage classification are disclosed. An example method for processing packets includes receiving a data packet at a first processing stage and examining the packet at the first processing stage to determine a first attribute of the packet. Based on the first attribute, a first classification is assigned to the packet. In the example method, the packet and the first classification are communicated from the first processing stage to a second processing stage and the packet is examined at the second processing stage to determine a second attribute of the packet. Based on the second attribute, a second classification is assigned to the packet. The example method further includes processing the packet based on the first classification and the second classification.

Abstract: A network switch and a method thereof for network communications include a first data port interface and a second data port interface supporting a data port transmitting and receiving data at a first data rate and a second data rate, respectively. The switch has a CPU interface to communicate with a CPU and a memory management unit to communicate data from at least one of the first and second data port interfaces and a memory. The switch includes a communication channel communicating data and messaging information between the first and second data port interfaces and the memory management unit and lookup tables, including an address resolution lookup table and a VLAN table. The first or second data port interfaces determine an egress port for an incoming data packet from a search of the address resolution lookup table and the VLAN table using a VLAN ID from the incoming data packet.

Abstract: A method of handling a datagram in a network device is disclosed. The steps include receiving a datagram, with the datagram having multiple field values, at a port of a network device, parsing the received datagram to obtain the field values, applying the parsed field values to a Ternary Content Addressable Memory (TCAM), determining matches between the parsed field values and predetermined criteria in the TCAM, indexing into a policy table based on the determined matches to obtain an action entry and taking an action based on the obtained action entry.

Abstract: A method of adjusting fields of a datagram in the handling of the datagram in a network device is disclosed. The method includes receiving a datagram, with the datagram having at least module identifier fields and port identifier fields, at a port of a network device, determining whether the received datagram is a unicast datagram, adjusting the module and port identifier fields of the datagram based on data registers in the network device when the received datagram is a unicast datagram and forwarding the datagram based on the module and port identifier fields of the datagram. The port of the network device is connected to a legacy device, where the legacy device has a reduced handling capacity when compared to the network device.

Abstract: A method for managing congestion in a stack of network switches includes the steps of receiving an incoming packet on a first port of a network switch for transmission to a destination port and determining if the destination port of the packet is a monitored port. Thereafter, the method determines a queue status of the destination port, if the destination port is determined to be a monitored port, and preschedules transmission of the incoming packet to the destination port if the destination port is determined to be a monitored port.

Abstract: A method for selectively controlling the flow of data through a network device is discussed. The network device has a plurality of ports, with each port of the plurality of ports having a plurality of priority queues. Congestion at one priority queue of the plurality of priority queues is detected and a virtual channel message is sent to other network devices connected to the network device causing data destined for the one priority queue to be halted. After the congestion at the one priority queue has abated, a virtual channel resume message is sent to the other network devices.

Abstract: A network device for selecting a port from a trunk group to transmit a unicast packet on the selected port. The network device includes at least one trunk group including a plurality of physical ports. The network device also includes a table with a plurality of entries. Each entry is associated with one trunk group and includes a plurality of fields that are associated with ports in the trunk group. Each entry also includes a hash field that is used to select bits from predefined fields of an incoming unicast packet to obtain an index bit for accessing one of the plurality of fields. The network device further includes transmitting means for transmitting the unicast packet to a port associated with an accessed one of the plurality of fields.

Abstract: A method of mirroring data to a mirrored to port in a plurality of switches. The method has the steps of determining if data was sent to all of said plurality of switches; determining if said data was sent to a mirrored to port (MTP); and resending said data to all of said plurality of switches if mirroring is enabled and said data was not sent to said MTP.

Abstract: A network device for selecting a port from a trunk group to transmit a unicast packet on the selected port. The network device includes at least one trunk group including a plurality of physical ports. The network device also includes a table with a plurality of entries. Each entry is associated with one trunk group and includes a plurality of fields that are associated with ports in the trunk group. Each entry also includes a hash field that is used to select bits from predefined fields of an incoming unicast packet to obtain an index bit for accessing one of the plurality of fields. The network device transmits the unicast packet to a port associated with an accessed one of the plurality of fields.

Abstract: A method of handling data packets in a series of network switches includes receiving an incoming data packet at a data port of a first switch of the series of network switches. A module id bitmap of the incoming data packet is resolved and a bit corresponding to the first switch of the module id bitmap is examined to determine if the bit is set. A destination address of the incoming data packet is resolved when the corresponding bit is set and the incoming data packet is forwarded or dropped based on the destination address. When the corresponding bit is not set, the incoming data packet is forwarded to a next switch of the series of network switches. A network switch configured to allow for cascading of data packets is also disclosed.

Abstract: Methods and apparatus for communicating data traffic using switch fabric dispersion are disclosed. An example apparatus includes a first tier of switch elements; and a second tier of switch elements operationally coupled with the first tier of switch elements. In the example apparatus, the first tier of switch elements is configured to receive a data packet from a source. The first tier of switch elements is also configured to route the data packet to the second tier of switch elements in accordance with a dispersion function, where the dispersion function is based on a dispersion tag associated with the data packet. The first tier of switch elements is still further configured to transmit the data packet to a destination for the data packet after receiving it from the second tier of switch elements.

Abstract: A method for selectively controlling the flow of data through a network device is discussed. The network device has a plurality of ports, with each port of the plurality of ports having a plurality of priority queues. Congestion at one priority queue of the plurality of priority queues is detected and a virtual channel message is sent to other network devices connected to the network device causing data destined for the one priority queue to be halted. After the congestion at the one priority queue has abated, a virtual channel resume message is sent to the other network devices.

Abstract: A network device for selecting a port from a trunk group on which to transmit a multicast packet. The network device includes at least one trunk group including a plurality of physical ports. The network device is connected to at least one other network device by a number of the plurality of physical ports. The network device also includes a table with a plurality of entries, wherein each entry is associated with the number of the plurality of physical ports on the network device. Each entry specifies if a packet should be transmitted on one of the plurality of physical ports.

Abstract: A data switch for network communications includes a first data port interface and a second data port interface is provided supporting at least one data port transmitting and receiving data. A CPU interface is provided, with the CPU interface configured to communicate with a CPU. A common memory is provided, and communicates with the first data port interface and the second data port interface. A memory management unit is provided, and communicates data from the first data port interface and the second data port interface and a common memory. At least two sets of communication channels are provided, with each of the communication channels communicating data and messaging information between the first data port interface, the second data port interface, and the memory management unit.

Abstract: A method of distributing data across a network having a plurality of equal-cost paths. Also, a device for distributing data over a network according to the method. The data, which is typically contained in data packets, may be distributed based on at least one attribute of each of the packets. The data may also be distributed according to a weighted distribution function that allows for unequal amounts of traffic to be distributed to each of the equal-cost paths.

Abstract: A method of distributing data across a network having a plurality of equal-cost paths. Also, a device for distributing data over a network according to the method. The data, which is typically contained in data packets, may be distributed based on at least one attribute of each of the packets. The data may also be distributed according to a weighted distribution function that allows for unequal amounts of traffic to be distributed to each of the equal-cost paths.