Abstract: Methods and apparatus for swapping functionality modes of a network data link are disclosed. An example method includes, in a network device, supporting a plurality of active network data links that includes a given network data link, where the given network data link is operated in accordance with a first mode of functionality.

Abstract: Methods and apparatus for dual hash tables are disclosed. An example method includes logically dividing a hash table data structure into a first hash table and a second hash table, where the first hash table and the second hash table are substantially logically equivalent. The example method further includes receiving a key and a corresponding data value, applying a first hash function to the key to produce a first index to a first bucket in the first hash table, and applying a second hash function to the key to produce a second index to a second bucket in the second hash table. In the example method the key and the data value are inserted in one of the first hash table and the second hash table based on the first index and the second index.

Abstract: A method of handling datagrams in a network device is disclosed. The method includes the steps of receiving an incoming datagram at a port of the network device, determining a type for the incoming datagram based on fields in the incoming datagram and a destination address, adding a tag to the datagram to assist in routing the datagram, obtaining a multiprotocol label switching (MPLS) label when the datagram is a MPLS datagram, processing the datagram based on the MPLS label and the destination address and discarding or forwarding the datagram based upon the processing step. The tag is stripped from the datagram before it is sent from an egress port of the network switch.

Abstract: Various example embodiments are disclosed. According to an example embodiment, a method may include receiving a token count units instruction, periodically increasing or decreasing a token count based at least in part on a refresh rate, and in response to receiving a packet, decreasing or increasing the token count based at least in part on a size of the packet and the instruction.

Abstract: Methods and apparatus for performing parity and/or ECC operations are disclosed. An example method includes determining that an opcode is being transmitted on a bus and determining if the transmitted opcode is a memory operation. In the event the transmitted opcode is a memory write operation, the example method includes calculating a parity bit for data associated with the opcode, writing the calculated parity bit to a parity table and writing the data to a memory. The example method also includes, in the event the transmitted opcode is the memory read operation, recovering data from a previously written memory, calculating a parity bit for the recovered data, recovering a previously stored parity bit for the recovered data, comparing the parity bit for the recovered data with the previously stored parity bit and, in the event the recovered data parity bit does not match the previously stored parity bit, providing an error notification.

Abstract: Methods and apparatus for swapping functionality modes of a network data link are disclosed. An example method includes, in a network device, supporting a plurality of active network data links that includes a given network data link, where the given network data link is operated in accordance with a first mode of functionality.

Abstract: A method of mediating the flow of datagrams to a destination in a network is disclosed. The method includes the steps of receiving a datagram at a port of a network device, evaluating a destination address for the datagram based on fields in the incoming packet, searching a longest prefix match (LPM) table using the destination address as a LPM key, determining an address table index and an offset based on entries found in the search of the longest prefix match table, searching an address table using the address table index and the offset as an address key to determine an egress port number of the network device and forwarding the packet based upon at least the egress port number.

Abstract: Various example embodiments are disclosed. According to an example embodiment, a method may include receiving a token count units instruction, periodically increasing or decreasing a token count based at least in part on a refresh rate, and in response to receiving a packet, decreasing or increasing the token count based at least in part on a size of the packet and the instruction.

Abstract: Methods and apparatus for dual hash tables are disclosed. An example method includes logically dividing a hash table data structure into a first hash table and a second hash table, where the first hash table and the second hash table are substantially logically equivalent. The example method further includes receiving a key and a corresponding data value, applying a first hash function to the key to produce a first index to a first bucket in the first hash table, and applying a second hash function to the key to produce a second index to a second bucket in the second hash table. In the example method the key and the data value are inserted in one of the first hash table and the second hash table based on the first index and the second index.

Abstract: A method of handling data packets in a network device is disclosed. The method includes the steps of receiving an incoming packet at a port of the network device, determining a destination address for the incoming packet based on fields in the incoming packet and filtering the incoming packet through a fast filtering processor through the application of filter masks to determine at least one label of a virtual channel label and a differentiated services label. The method also includes modifying the at least one label and a classification of the incoming packet based when a result returned from a rules table indicates that the at least one label should be changed, producing an outgoing packet based on the filtering of the incoming packet; and discarding or forwarding the outgoing packet based upon the filtering.

Abstract: A method of handling datagrams in a network device is disclosed. The method includes the steps of receiving an incoming datagram at a port of the network device, determining a type for the incoming datagram based on fields in the incoming datagram and a destination address, adding a tag to the datagram to assist in routing the datagram, obtaining a multiprotocol label switching (MPLS) label when the datagram is a MPLS datagram, processing the datagram based on the MPLS label and the destination address and discarding or forwarding the datagram based upon the processing step. The tag is stripped from the datagram before it is sent from an egress port of the network switch.

Abstract: A method of mediating the flow of datagrams to a destination in a network is disclosed. The method includes the steps of receiving a datagram at a port of a network device, evaluating a destination address for the datagram based on fields in the incoming packet, searching a longest prefix match (LPM) table using the destination address as a LPM key, determining an address table index and an offset based on entries found in the search of the longest prefix match table, searching an address table using the address table index and the offset as an address key to determine an egress port number of the network device and forwarding the packet based upon at least the egress port number.