Abstract: Techniques to avoid polarization in a communication network include a network switch or device having a first interface to receive a data unit or packet, and a second interface via which the packet is transmitted from the network device. The network device includes a hash value generator configured to generate, using a depolarizer, a depolarized key from an initial key (where the initial key is based on contents of the packet and the depolarizer is unique to the network device), and to generate a hash value based on the depolarized key and the packet by using a hash function that is common to all network devices in the network. The hash value may be optionally modified to load balance egress traffic of the network device. The network device selects an egress link or port, such as by determining an index into an egress table based on the (modified) hash value.

Abstract: A forwarding engine in a network device selects one or more groups of multiple egress interfaces of the network device for forwarding packets received by the network device. An egress interface selector in the network device selects individual egress interfaces within the one or more groups selected by the forwarding engine. The egress interface selector includes a table associated with a first group of multiple egress interfaces, wherein elements in the table include values indicate individual egress interfaces in the first group. When the forwarding engine selects the first group, a table element selector of selects an element in the table to identify the individual egress interface for forwarding the packet.

Abstract: A method for maintaining time at a network device includes receiving a packet that (i) conforms to a protocol that does not define a dedicated field for time correction and (ii) includes a time stamp specifying a time, determining whether the received packet includes an existing field specifying time correction information to be used for correcting the time specified by the time stamp, and, in response to determining that the packet does not include an existing field specifying time correction information, adding to the packet a new field specifying time correction information to be used for correcting the time specified by the time stamp.

Abstract: A method for processing packets, in a network device including at least one processing engine that i) is not configured to process destination information that conforms to a first protocol and ii) is configured to process destination information that conforms to a second protocol, includes receiving a packet at the network device, and determining, in the network device, first destination information included in the packet. The first destination information conforms to the first protocol. The method also includes generating, in the network device, second destination information conforming to a third protocol based on the first destination information. The method also includes generating, in the network device, third destination information conforming to the second protocol based on the second destination information. The method also includes processing the packet with the at least one processing engine included in the network device using the third destination information.

Abstract: A network edge bridge including a first communication unit configured to receive a data packet from an access segment of a network, the data packet including a tunnel destination address and at least one Virtual Local Area Network (VLAN) tag, a tunnel header constructing unit configured to construct a tunnel header based on the VLAN tag. And a second communication unit that transmits the data packet, including the tunnel header, to an egress device corresponding to the tunnel destination address via an overlay interconnection layer.

Abstract: A packet received by a network device is associated with a sequence number indicative of an order of transmission of the packet within a sequence of packets received by the network device. The network device determines whether the sequence number associated with the packet meets a first condition or a second condition for determining whether the packet is a duplicate of at least one other packet previously received by the network device. In response to determining that the sequence number meets the first condition, the network device deterministically determines whether the packet is a duplicate based on a record of previously received sequence numbers stored in a memory of the network device. In response to determining that the sequence number meets the second condition, the network device probabilistically determines whether the packet is a duplicate based on historical data maintained by the network device.

Abstract: A method for forwarding FCoE packets in a network switching device includes receiving a first packet at the network switching device via an Ethernet link, determining, in the network switching device, an FC destination identifier included in the first packet, updating, in the network switching device, an Ethernet address based on the FC destination identifier, generating, in the network switching device, a first TRILL destination identifier based on the updated Ethernet address, and causing, in the network switching device, the first packet to be forwarded to a different device based on the first TRILL destination identifier.

Abstract: A transparent edge Routing Bridge (RBridge) including a first communication unit configured to receive a data packet from an access segment of a network, the data packet including an egress device nickname and at least one Virtual Local Area Network (VLAN) tag, a TRansparent Interconnection of Lots of Links (TRILL) header constructing unit configured to construct a TRILL header based on the VLAN tag, and a second communication unit that transmits the data packet, including the TRILL header, to an egress device corresponding to the egress device nickname via a TRILL compliant interconnection layer.

Abstract: A data packet is received, wherein the data packet includes i) a checksum and ii) a timestamp. The timestamp is modified to generate a modified timestamp. A checksum trailer value to maintain correctness of the checksum in the data packet having the modified timestamp is determined. At least a portion of i) an extension field of the data packet and/or ii) a padding field of the data packet is set to the checksum trailer value.

Abstract: A method for load balancing in a communication network having a plurality of link aggregate groups includes receiving a data unit at a first one of the plurality of network devices associated with a first one of the plurality of link aggregate groups, applying a hashing function to the data unit to generate a first hash value, where the first hash value identifies a communication link in the first one of the plurality of link aggregate groups, receiving the data unit at a second one of the plurality of network devices associated with a second one of the plurality of link aggregate groups, and applying the hashing function to the data unit to generate a second hash value that is distinct from the first value, where the second hash value identifies a communication link in the second one of the plurality of link aggregate groups along which the data unit is to be communicated.

Abstract: A device in a server having a processor and a storage. The device has a protocol blind network path indication unit configured to obtain an indicator corresponding to a predetermined path to a data communication unit in the network using a destination address of a received data packet, an upstream communication unit configured to transmit a network protocol blind packet including the data packet and the indicator corresponding to the predetermined data path to the data communication unit in the network, a combiner configured to bind the indicator to the data packet received by the downstream communication unit, and a protocol blind correlation storage unit configured to provide information related to target addresses and indicators corresponding to a plurality of predetermined data paths in the network. The protocol blind network path indication unit obtains the indicator corresponding to a predetermined path by accessing the protocol blind correlation structure.

Abstract: A packet transmitted by a master clock via a network is received via a port of a network device. The packet includes a time stamp from the master clock. It is determined via which one of a plurality of communication path in the network the packet was received. An application layer module of the network device uses (i) the time stamp in the packet and (ii) the determination of the communication path to determine time information.

Abstract: A device in a server having a processor and a storage. The device has a protocol blind network path indication unit configured to obtain an indicator corresponding to a predetermined path to a data communication unit in the network using a destination address of a received data packet, an upstream communication unit configured to transmit a network protocol blind packet including the data packet and the indicator corresponding to the predetermined data path to the data communication unit in the network, a combiner configured to bind the indicator to the data packet received by the downstream communication unit, and a protocol blind correlation storage unit configured to provide information related to target addresses and indicators corresponding to a plurality of predetermined data paths in the network. The protocol blind network path indication unit obtains the indicator corresponding to a predetermined path by accessing the protocol blind correlation structure.

Abstract: An apparatus for forwarding packets includes a packet processing pipeline having a processing unit that processes packets compliant with a recognized communication protocol. A first port coupled to the packet processing pipeline is configured to receive a packet that does not comply with the recognized communication protocol and has a header that conforms to a second communication protocol. A data extraction unit extracts first destination information from the header of the packet and, based on the first destination information, generates second destination information that conforms to the recognized communication protocol. The processing unit determines, based on the second destination information, an egress interface to which the packet is to be forwarded.

Abstract: In a network device communicatively coupled to a master clock via a plurality of different communication paths, a clock synchronization module is configured to determine a plurality of path time data sets corresponding to the plurality of different communication paths based on signals received from the master clock via the plurality of different communication paths between the network device and the master clock. A clock module is configured to determine a time of day as a function of the plurality of path time data sets.

Abstract: In a modular switching device that includes a plurality of packet processors interconnected by a plurality of connecting devices, one or more data packets are received at a first packet processor. The first packet processor generates a communication frame that includes at least a portion of a first data packet among the one or more data packets. The first packet processor divides the communication frame into a plurality of transmission units, includes a communication frame identifier in respective transmission units, and includes a respective position identifier in respective transmission units. The transmission units are transmitted to the plurality of connecting devices via a first plurality of uplinks, and the plurality of connecting devices transmits the transmission units to the second packet processor via a second plurality of uplinks. The communication frame is reassembled from the plurality of transmission units using the communication frame identifier and the position identifiers.

Abstract: A multi-stage switching system comprises a first stage including a plurality of groups of switching devices. Each group of switching devices includes more than one switching device, and each group of switching devices is associated with a corresponding single device identifier (ID). A second stage includes a plurality of switching devices. The switching devices of the first stage are coupled to the switching devices of the second stage via a plurality of uplinks. Switching devices of the first stage are configured to associate a target device ID and a target port ID to a data unit received via a front port of the switching system. The switching devices of the first stage and the switching devices of the second stage are configured to direct the data unit through the switching system using the target device ID and a target port ID.

Abstract: First data units corresponding to a first multicast group (MCG) and second data units corresponding to a second MCG are stored in a first queue of a network switching device. At least one first data unit retrieved from the first queue and at least one second data unit retrieved from the first queue are aggregated into a first frame. The first frame is transmitted by the network switching device to a superset MCG that includes at least the first MCG and the second MCG. Only third data units corresponding to a third MCG are stored in a second queue of the network switching device. Third data units retrieved from the second queue are transmitted by the network switching device to the third MCG.

Abstract: In a network device communicatively coupled to a master clock via a plurality of different communication paths, a clock synchronization module is configured to determine a plurality of path time data sets corresponding to the plurality of different communication paths based on signals received from the master clock via the plurality of different communication paths between the network device and the master clock. A clock module is configured to determine that at least one of the plurality of path time data sets is inaccurate based on accuracy metrics corresponding to the plurality of path time data sets, and determine a time of day as a function of a remainder of one or more path time data sets, in the plurality of path time data sets, not determined to be inaccurate. The device may detect and/or mitigate “man-in-the-middle” attacks aimed at a clock synchronization protocol.

Abstract: In a network device communicatively coupled to a master clock via a plurality of different communication paths, a clock synchronization module is configured to determine a plurality of path time data sets corresponding to the plurality of different communication paths based on signals received from the master clock via the plurality of different communication paths between the network device and the master clock. A clock module is configured to determine that at least one of the plurality of path time data sets is inaccurate based on accuracy metrics corresponding to the plurality of path time data sets, and determine a time of day as a function of a remainder of one or more path time data sets, in the plurality of path time data sets, not determined to be inaccurate. The device may detect and/or mitigate “man-in-the-middle” attacks aimed at a clock synchronization protocol.