Abstract: A method of handling packets includes inserting a stack-specific tag into a packet, then processing the packet in a stack of network switches in accordance with tag information in the stack-specific tag. The stack-specific tag is then removed from the packet.

Abstract: An apparatus and method for switching VOIP packets in a data network, wherein the method includes the steps of receiving a first packet in a network switch and determining if the first packet is a VOIP packet. Further, method includes determining a dynamically negotiated VOIP port for a VOIP session from at least one of the first packet and a second packet received in the network switch, if the first packet is determined to be the VOIP packet. Finally, the method includes the steps of classifying all subsequent VOIP packets corresponding to the dynamically negotiated VOIP port in accordance with predetermined parameters. The apparatus includes a network switch having at least one data port interface controller supporting a plurality of data ports for transmitting and receiving data, and a fast filtering processor in communication with the at least one data port interface.

Abstract: A network device for uniform distribution of non-unicast traffic, such as layer 2 broadcast, layer 2 multicast, unknown unicast and layer 3 multicast on a truch group. 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. The network device further includes hashing means for hashing a predefined number of bits from predefined fields in the packet to select one entry in the table. The selected entry is used to identify a destination port. The network device also includes transmitting means for transmitting the packet to the destination port.

Abstract: A network device for processing packets. The network device includes applying specific fields from a packet to an associated memory device and comparing means for comparing input to the memory device with entries in the memory device. The network device also includes enabling means for enabling selection of bits, by the memory device, that are required to match exactly with bits from the input to the memory device. The network device further includes outputting means for outputting an address for a matched entry by the memory device and applying means for applying a match from the memory device to an associated entry in a table for applying actions from the table that are associated with the match to the packet.

Abstract: An apparatus comprising a managed network interface configured to receive data from, and transmit data to, a managed network, wherein the managed network comprises a plurality of managed devices configured to queue and transmit data; an unmanaged network interface configured to receive data from, and transmit data to, an unmanaged network, wherein the unmanaged network is configured to request the amelioration of network congestion experienced by the unmanaged network; and a congestion manager configured to receive a network congestion amelioration request from the unmanaged network, ameliorate network congestion by controlling the rate of information forwarded from the managed network to an unmanaged network, and dynamically alter the rate of information forwarded from the managed network to the unmanaged network.

Abstract: An apparatus comprising a virtual queue configured to virtually receive virtual data units as the data units are actually received by a real queue. In various embodiments, the virtual queue may include a committed token counter (CTC) configured to represent a number of bytes available to be allocated to a committed burst having a maximum size. In such an embodiment, the virtual queue may include an excess token counter (ETC) configured to represent a number of bytes available to be allocated to an excess burst having a maximum size. In one embodiment, a token counter incrementer configured to, as an exiting data unit virtually exits the virtual queue, increment either the committed token counter or the excess token counter.

Abstract: A switch assembly having multiple blades in a chassis and a method of using that assembly to switch data is disclosed. A network switch assembly for network communications includes at least one fabric blade and a plurality of port blades. The at least one fabric blade has at least one switch having a plurality of data port interfaces, supporting a plurality of fabric data ports transmitting and receiving data, and a CPU interface, where CPU interface is configured to communicate with a CPU. The at least one fabric blade also has a CPU subsystem communicating with the CPU interface. Each of said plurality of port blades has at least one switch having a plurality of data port interfaces, supporting a plurality of port data ports transmitting and receiving data.

Abstract: A network switch includes a plurality of egress ports configured to send packets of data traffic to at least one receiving network device and a plurality of ingress ports configured to receive the packets of data traffic from at least one sending network device. The switch further includes a switch logic engine configured to define multiple flows of data through the switch from a sending network device to a receiving network device and to route the flows from the ingress port to the egress port, a flow monitor configured to measure at least one flow attribute of the flows, and a flow regulation engine configured to regulate a flow rate of flows sent by a sending network device based at least in part on a measurement by the flow monitor of the at least one flow attribute of the packets.

Abstract: A switch assembly having multiple blades in a chassis and a method of using that assembly to switch data is disclosed. A network switch assembly for network communications includes at least one fabric blade and a plurality of port blades. The at least one fabric blade has at least one switch having a plurality of data port interfaces, supporting a plurality of fabric data ports transmitting and receiving data, and a CPU interface, where CPU interface is configured to communicate with a CPU. The at least one fabric blade also has a CPU subsystem communicating with the CPU interface. Each of said plurality of port blades has at least one switch having a plurality of data port interfaces, supporting a plurality of port data ports transmitting and receiving data.

Abstract: A network switch including at least one data port interface supporting a plurality of data ports, at least one stack link interface configured to transmit data between the network switch and other network switches, and a CPU interface configured to communicate with a CPU. A memory management unit in communication with the at least one data port interface and the at least one stack link interface is provided along with a memory interface in communication with the at least one data port interface and the at least one stack link interface, wherein the memory interface is configured to communicate with a memory.

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 for switching packets from a source to a destination includes a source port for receiving an incoming packet from a source, a destination port which contains a path to a destination for the packet, and a filter unit for constructing and applying a filter to selected fields of the incoming packet. The filter unit further includes filtering logic for selecting desired fields of the incoming packet and copying selected field information therefrom. The filtering logic also constructs a field value based upon the selected fields, and applies a plurality stored field masks on the field value. The switch additionally includes a rules table which contains a plurality of rules therein. The filtering logic is configured to perform lookups of the rules table in order to determine actions which must be taken based upon the result of a comparison between the field value and the stored filter masks and the rules table lookup.

Abstract: A method of forwarding data in a network switch fabric is disclosed. An incoming data packet is received at a first port of the fabric and a first packet portion, less than a full packet length, is read to determine particular packet information including an opcode value. The opcode value allows the fabric to determine the packet type, such a a whether the packet is a broadcast packet, a unicast packet, a multicast packet, etc. Based on the opcode value read, a particular forwarding table of a plurality forwarding tables is read and an egress port bitmap is determined based on entries read from the particular forwarding table. The incoming data packet is then forwarded based on the egress port bitmap. In addition, the architecture of the switch fabric is also disclosed.

Abstract: A network switch including at least one data port interface supporting a plurality of data ports, at least one stack link interface configured to transmit data between the network switch and other network switches, and a CPU interface configured to communicate with a CPU. A memory management unit in communication with the at least one data port interface and the at least one stack link interface is provided along with a memory interface in communication with the at least one data port interface and the at least one stack link interface, wherein the memory interface is configured to communicate with a memory.

Abstract: A method for establishing a virtual channel between network devices is disclosed. In the case of a local network device establishing a virtual channel with a remote network device, a virtual channel request message is sent from the local network device to the remote network device. A virtual channel acknowledgement message and a remote capability list are received and a virtual channel resume message and a local capability list are sent. The virtual channel is then enabled. In the case of a remote network device establishing a virtual channel with a local network device, a virtual channel request message is received from a local network device by a remote network device. A virtual channel acknowledgement message and a remote capability list are sent and a virtual channel resume message and a local capability list are received. The virtual channel is then enabled.

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 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 method for establishing a virtual channel between network devices is disclosed. In the case of a local network device establishing a virtual channel with a remote network device, a virtual channel request message is sent from the local network device to the remote network device. A virtual channel acknowledgement message and a remote capability list are received and a virtual channel resume message and a local capability list are sent. The virtual channel is then enabled. In the case of a remote network device establishing a virtual channel with a local network device, a virtual channel request message is received from a local network device by a remote network device. A virtual channel acknowledgement message and a remote capability list are sent and a virtual channel resume message and a local capability list are received. The virtual channel is then enabled.

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 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.