Abstract: A method and apparatus for providing TCAM functionality in a custom integrated circuit (IC) is presented. An incoming key is broken into a predefined number of sub-keys. Each sub-key is sued to address a Random Access Memory (RAM), one RAM for each sub-key. An output of the RAM is collected for each sub-key, each output comprising a Partial Match Vector (PMV). The PMVs are bitwise ANDed to obtain a value which is provided to a priority encoder to obtain an index. The index is used to access a result RAM to return a result value for the key.

Abstract: A method, apparatus and computer program product for implementing port selection via synchronized port state databases maintained by the forwarding plane of a network element is presented. Each Forwarding Data Unit (FDU) within the forwarding plane of the network element maintains a respective port state database, each port state database containing a synchronized view of the port state for all ports within the network element. A port selection process is performed by each port state database upon request of its associated FDU, to identify an available port in an UP state associated with a Multi-Link Trunk (MLT) to enable fast reroute between ports associated with the MLT in the event of port failure. The process returns an identified port to the FDU for use by the FDU to forward the packet.

Abstract: A network switch configures a static forwarding to a packet processor by suppressing packet switching and forwards all traffic received on a group of ports a trunk port for aggregation. A trunk header is overloaded with message classification information for use at the downstream packet processor. Routing logic retrieves the packet classification information and stores the information in control fields that are ignored due to the static forwarding and local switching disablement. The static forwarding forwards the packet, with the appended classification information, to a packet processor via the aggregation port. Packet classification information is indicative of the type of the message traffic and is performed upon packet arrival at the switching device.

Abstract: A method, apparatus and computer program product for providing Split Multi Link Trunk (SMLT) for Advanced Technology Attachment (ATA) Over Ethernet is presented. All ports on an ATA server are assigned a same Media Access Control (MAC) address. When the first switch receives a packet destined to the second switch the first switch performs a route lookup on a destination address of the packet and forwards the packet to the target over one of the second plurality of links, and when the second switch receives a packet destined to the first switch the second switch performs a route lookup on a destination address of the packet and forwards the packet to the target over one of the second plurality of links.

Abstract: A method, apparatus and computer program product for providing fast reroute of a packet is presented. A unicast packet is received by an FDU in a data plane of a network element and a destination is determined for the packet. A lookup is performed in a port state table maintained by the FDU to determine an available local port that is in an UP state for the destination, and if no local port is UP, then a lookup is performed in the port state table to determine an available remote port that is in an UP state for the destination. If a port in the UP state cannot be determined for the unicast packet, then the packet is dropped.

Abstract: A method, apparatus and computer program product for providing fast reroute of a packet that may be forwarded on one of a plurality of Equal Cost Multi Path (ECMP) routes through a network is presented. A packet is received by a Forwarding Data Unit (FDU) in a data plane of a network element. The unicast packet is routed at L3, and ECMP is enabled for a next hop for the unicast packet. An ECMP route is selected for forwarding the packet to a destination port. A lookup is performed in a port state table maintained by the FDU to determine an available local port for said ECMP route that is in an UP state for the destination, and if no local port is UP, then a lookup is performed in the port state table to determine an available remote port that is in an UP state for the selected ECMP route.

Abstract: A method, apparatus and computer program product for providing a fast re-route of a multicast packet within a network element to an available port associated with a multi-link trunk is presented. A packet is received by a Forwarding Data Unit (FDU) in a data plane of a network element and a determination made that the packet is a multicast packet. The packet is forwarded to all egress FDUs having at least one port associated with at least one receiver of the multicast packet. A lookup is performed by each egress FDU in a synchronized local port state database to find a port for each receiver that is in an UP state. The packet is forwarded out the port to a receiver when the port is in the UP state and dropped when the port is in the DOWN state.

Abstract: A method, apparatus and computer readable medium for maintaining two variables per port member of a network device which is part of a Split Multi Link Trunk/Link Aggregation Group (SMLT/LAG) is presented. A first variable comprising a link status variable reflecting a link status, and a second variable comprising a forwarding status variable reflecting a forwarding status of a forwarding plane with respect to the port are provided, the link status variable and the forwarding status variable in a first state when the port is operating properly. A failure related to the port is detected. The link status variable is set to a second state, and the forwarding status variable is set to a second state.

Abstract: A method, apparatus and computer program product are presented. In a system having at least one Multi Link Trunk/Link Aggregation Group (MLT/LAG), a table is provided for each MLT/LAG, each table having at least one entry, each entry including at least two fields, a first field comprising a port member identification (ID) field and a second field comprising a port member status field. A port member status is checked for a port when a packet flow hashes into the table, and the status for the port member is determined. When the port member status is in a first state, then the associated port member ID is used as a destination port to transmit to. When the port member state is in a second state, then a next entry in the port table is accessed to find a next available entry having a port member status that is in the first state and the corresponding port member ID of the port member state that is in the first state is used as a destination port to transmit to. The first state is UP and the second state is DOWN.

Abstract: In an Ethernet network element comprising at least one line interface element and a central processing unit (CPU) to control forwarding of data packets at the network element, a method comprising receiving continuity check messages (CCMs) at the at least one line interface element, and processing the CCMs in the at least one line interface element to provide continuity checks for connections to the network element without requiring processing of CCMs by the CPU.

Abstract: A method, apparatus and computer program product for temporal-based flow distribution across multiple packet processors is presented. A packet is received and a hash identifier (ID) is computed for the packet. The hash ID is used to index into a State Table and to retrieve a corresponding record. When a time credit field of the record is zero then the time credit field is set to a to a new value; a Packet Processing Engine (PE) whose First-In-First-Out buffer (FIFO) has the lowest fill level is selected; and a PE number field in the state table record is updated with the selected PE number. When the time credit field of the record is non-zero then the packet is sent to a PE based on the value stored in the record; and the time credit field in the record is decremented if the time credit field is greater than zero.

Abstract: A method, apparatus and computer program product for performing efficient loop instruction execution using bit vector scanning is presented. A bit vector is scanned, each bit in the bit vector representing at least one of a feature and a conditional status. The presence of a bit of said bit vector set to a first state is detected. The bit is set to a second state. An instruction address for a routine corresponding to said bit set to a first state is looked up using a bit position of said bit that was set to a first state. The routine is executed. The scanning, said detecting, said setting and said using are repeated until there are no remaining bits of said bit vector set to said first state.

Abstract: A switch device can be configured to operate in a manner that was not originally intended. For example, a switch device can be a Broadcom XGS type of device that is configured with a packet-processing unit to perform line speed lookups in accordance with a default configuration. The default configuration can include classifying and forwarding received packets to an upstream interface based on VLAN information. The default configuration can be overwritten such that the switch device operates in a different manner than originally intended. For example, the switch device can be reconfigured to include mapping rules that specify different QoS data to be assigned to different type of received packets. Subsequent to utilizing the maps to identify QoS information for received packets, the reconfigured switch device uses the QoS information to forward the packets to queues in an upstream interface.

Abstract: A network element disposed at an edge of a connectivity fault management (CFM) domain includes a switch fabric, a central processor (CP) card, and a line card in communication with the CP card through the switch fabric. The line card includes an Ethernet interface for transmitting and receiving Ethernet CFM frames over a network and circuitry configured to generate new continuity check messages (CCMs) periodically, to process CCMs received on each connection supported by the line card, and to detect a loss of continuity for any of the connections supported by the line card. The line card maintains a list of supported connections. A generate timer and an age counter are associated with each connection in the list. The line card generates a CCM for a given connection when the generate timer expires and detects a loss of continuity for the given connection when its age counter exceeds a threshold.

Abstract: A method, apparatus and computer program product for providing scalable storage virtualization is presented. Storage virtualization management functions are provided in a first device, and storage virtualization Input/Output (I/O) functions are provided in a second device. An interface is provided between the first device and the second device, wherein the first device manages and updates I/O functions of the second device. I/O operations are performed between the second device and at least one storage device.

Abstract: Methods and apparatus provide for a Packet Policer. The Packet Policer determines a first amount of tokens based on an interval occurring between receipt of a first packet and receipt of a second packet, where the first packet was received before the second packet. The Packet Policer determines a second amount of tokens based on a size of the second packet. The Packet Policer then updates a token bucket with the first amount of tokens as the second amount of tokens is removed from the token bucket.

Abstract: A network switch configures a static forwarding to a packet processor by suppressing packet switching and forwards all traffic received on a group of ports a trunk port for aggregation. A trunk header is overloaded with message classification information for use at the downstream packet processor. Routing logic retrieves the packet classification information and stores the information in control fields that are ignored due to the static forwarding and local switching disablement. The static forwarding forwards the packet, with the appended classification information, to a packet processor via the aggregation port. Packet classification information is indicative of the type of the message traffic and is performed upon packet arrival at the switching device.

Abstract: A method, apparatus and computer program product for Media Access Control (MAC) address learning and learning rate suppression are presented. A Forwarding Data Unit (FDU) maintains two cache tables, each of the cache tables used for harvesting MAC addresses. The FDU uses the cache tables in an alternating manner, wherein when one of the cache tables is used for harvesting MAC addresses the other one of the cache tables has its contents bundled into a packet for forwarding to a control plane of the FDU.

Abstract: A method and apparatus for branch reduction in a multithreaded packet processor is presented. An instruction is executed which includes testing of a branch flag. The branch flag references a configuration bit vector wherein each bit in the configuration bit vector corresponds to a respective feature. When said branch flag returns a first result processing is continues at an instruction located at a first location relative to a Program Counter (PC) and when the branch flag returns a second result processing is continued at a second location relative to said PC.

Abstract: A method, apparatus and computer program product for performing TCAM lookups in multi-threaded packet processors is presented. A Ternary Content Addressable Memory (TCAM) key is constructed for a packet and a Packet Reference Number (PRN) is generated. The TCAM key and the packet are tagged with the PRN. The TCAM key and the PRN are sent to a TCAM and in parallel the packet and the PRN are sent to a packet processing thread. The PRN is used to read the TCAM result when it is ready.