Abstract: A network element and method for programming a network element that includes detecting an update to a first route in a routing information base (RIB) is disclosed. The method includes locating a first route network prefix associated with the first route within a network prefix trie (NPT); determining that, prior to the update, a first parent network prefix and the first route network prefix were reachable using a pair of different next hops connected to the network element; and determining that, after the update, the first parent network prefix and the first route network prefix are reachable using a first common next hop connected to the network element. The method also includes removing an existing forwarding information base (FIB) entry in the FIB associated with the first route network prefix.

Abstract: A method for optimizing network device resources that includes receiving, by an optimizer, first resource utilization data, making a first determination, based on the first resource utilization data, that resource utilization exceeds an upper threshold, starting, based on the first determination, an optimization process, that includes identifying a resource optimization entry of a resource class optimization queue, and initiating optimization of a resource fragment specified by the resource optimization entry. After initiating optimization of the region of the memory, the method additionally includes receiving second resource utilization data, making a second determination, based on the second resource utilization data, that the resource utilization is below a lower threshold, and halting, based on the second determination, the optimization process.

Abstract: Protocol-Independent Multicast (PIM) uses PIM hello messages to maintain neighborship information. PIM may be implemented in an Ethernet VPN (EVPN) providing Optimized Inter-Subnet Multicast (OISM). Techniques are disclosed for improving PIM neighborship efficiency and speed in an EVPN. An Inclusive Multicast Ethernet Tag (IMET) may be used to set PIM neighborship instead of using PIM hello messages and TCP may be used to determine if the neighbor is disconnected instead of tracking PIM timers.

Abstract: The present disclosure describes a network switch design that includes a vertical switch circuit board that is mounted parallel to the front panel of the network switch. The vertical circuit board supports switch chip(s) to process and forward packets and optical module connectors to receive pluggable optics modules that provide connections to other network switches. The arrangement of the circuit board, switch chip(s) and optical module connectors achieves reduced lengths for the electrical signal traces that connect the switch chip(s) to the optical module connectors. In addition, the design improves cooling by providing separate airflow regions between the switch chip heatsink(s) and the optics modules. The vertical switch card assembly and its components can be made removable from the front panel for ease of servicing.

Abstract: Hitless migration of network devices for communication between two data centers using a dual IP stack mode is provided herein. In a first data center, a first gateway receives first routing information from an edge device regarding a first set of routes associated with a first host device in the first data center. The first gateway device generates a second set of routes that include a first address of the edge device formatted according to a first communication protocol. The second set of routes is exported to a second gateway device in a second data center. The first gateway device receives an encapsulated data packet having a first overlay that includes the first address from the second gateway device. The first gateway device decapsulates and re-encapsulates the data packet and a re-encapsulated data packet is sent to the edge device, the re-encapsulated data packet having a second overlay that includes the second address.

Abstract: A network device can include a main processor and a packet processor. A method is provided that includes storing a table of values in the packet processor, using the packet processor to receive from the main processor a value that can be used to update the table of values, and using acceleration hardware in the packet processor to update the table of values based on the value received from the main processor without any additional interaction with the software running on the main processor.

Abstract: A method and system for propagating network traffic flows between end points based on service and priority policies. Specifically, the method and system disclosed herein entail configuring network elements with network-disseminated traffic management policies. Each traffic management policy guides the handling of a network traffic flow between origination and termination end points (i.e., source and destination hosts), which may be defined through data link layer, network layer, and/or transport layer header information, as well as group assignment information, associated with the source and destination hosts.

Abstract: A method and system for maintaining persistent network policies for a virtual machine (VM) that includes determining a name of the VM executing on a first host connected to a first network device; binding the name of the VM to a network policy for the VM on the first network device; acquiring from VM management software, using the name of the VM, a universally unique identifier (UUID) of the VM; associating the UUID to the network policy on the first network device; applying the network policy for the VM on the first network device; subscribing to receive notifications from the VM management software of changes to the configuration of the VM corresponding to the UUID; receiving notification from the VM management software of a configuration change made to the VM corresponding to the UUID; and updating the network policy of the VM to reflect the configuration change of the VM.

Abstract: In general, embodiments relate to a method for managing traffic flow along a path between network devices. The method includes initiating, by an end-point network device, monitoring of the path, wherein the end-point network device transmits packets to a target network device over the path, detecting after the initiating, by the end-point network device, that at least a portion of the path has failed, wherein the portion of the path that has failed is external to the end-point network device, in response to the detecting, identifying which portions of network device hardware in the source network device need to be updated to redirect the packets from the end-point network device to the target network device to take a second path, and updating the identified portions of the network device hardware.

Abstract: In general, embodiments relate to a method, for managing a network device, that includes accessing, by a feature agent of the network device, an allocation data structure, wherein the allocation data structure specifies a first portion of memory and a second portion of memory, identifying, using the allocation data structure, the first portion of the memory to be used during an upgrade, wherein the second portion of memory is used for storing a network device table, wherein the network device table is used by a packet transmission component while the upgrade is being performed, and upon completion of the upgrade, updating the allocation data structure to specify that the packet transmission component use a second network device table and stop using the network device table, wherein the second network device table is initially populated during the upgrade.

Abstract: Techniques for operating a network device are provided. In some embodiments, a method may comprise: forwarding multicast data packets from a source in a first customer network to a receiver in a second customer network; detecting that another PE device is forwarding the multicast data packets, wherein: Protocol Independent Multicast (PIM) is enabled on supplemental bridge domain (SBD) logical interfaces of the PE device and the another PE device, the PE device and the another PE device are PIM neighbors, and the PE device and the another PE device communicate with each other and with the receiver using the PIM protocol through an Ethernet virtual private network (EVPN). The method may further comprise: determining the another PE device is an assert winner from among the PE device and the another PE device based on at least one PIM assert message, the another PE device forwarding the multicast data packets.

Abstract: Synchronization of clocks among computing devices in a network includes determining master/slave relations among the computing devices. Some computing devices (e.g., switches) include trunk ports configured to carry traffic for several logical networks; e.g., virtual local area networks, VLANs. A trunk port can be associated with a master/slave setting for each logical network that it is configured for. Synchronization of clocks among the computing devices further includes running a synchronization sequence between a trunk port and each computing device on each of the logical networks configured on the trunk port.

Abstract: Management of a plurality of sub-tunnels is disclosed herein. Resource utilization of a plurality of sub-tunnels of a network tunnel implementing a Resource Reservation Protocol is monitored. A resource utilization of a first set of the sub-tunnels exceeding a defined utilization threshold is detected. As a result of the detection, an adjusted resource utilization is determined for a second set of the sub-tunnels. The resource utilization of the second set of sub-tunnels may be less than a defined utilization threshold. The adjusted resource utilization is established for the second set of sub-tunnels for a next measurement interval. The adjusted resource utilization of each sub-tunnel of the second subset of sub-tunnels may be less than a lowest resource utilization among the first set of sub-tunnels.

Abstract: A method and apparatus of a device that grows and/or shrinks a table that is shared between a writer and a plurality of readers is described. In an exemplary embodiment, a device receives an entry to be added to the shared table. In response to receiving the entry, the device remaps shared table to add a new storage segment to the shared table. The device further adds the entry to the shared table, where the entry is stored in the new storage segment. In addition, the device updates a shared table characteristic to indicate that the shared table has changed. The device further shrinks the shared table by remapping the table to remove a segment of the table.

Abstract: A system and method for provisionally authenticating a host moving from a source port of a switch device to a destination port of the switch device is disclosed. The host is initially authenticated at the source port and blocked from forwarding network traffic at the destination port. During a provisional authentication session, an authentication agent executing on the switch intercepts one or more authentication packets sourced by the host and headed for the destination port of the switch device and redirects the authentication packets to an authentication server for validating the host at the destination port of the switch device. The switch device removes the block at the destination port in response to receiving an acknowledgment of successful authentication at the destination port from the authentication server.

Abstract: A method for processing network communications, the method including receiving a network packet at a network device and performing at least one lookup for the packet in one or more first lookup tables in which the one or more first lookup tables are programmed to include at least one of an exact match or longest prefix match (LPM) table entry. The method includes obtaining a security source segment and a security destination segment based upon the result of the at least one lookup for the packet in the one or more first lookup tables. The method further includes performing a lookup in a second lookup table based upon the security source segment and security destination segment in which the second lookup table is programmed in a content addressable memory. Based upon the result of the lookup in the second lookup table, processing a forwarding decision for the packet according to the security source segment and security destination segment.

Abstract: A method for reverse path forwarding (RPF) selection by a network device connected to a network includes receiving an advertisement message from each of a plurality of neighbor devices within the network, parsing the advertisement message to determine a color identification (ID) of each of the neighbor devices, and selecting, from among the neighbor devices, a RPF device based on the color ID of each of the neighbor devices.

Abstract: A method and system for multicast flow restoration following network failure detection. Specifically, in addressing the aftermath following a network failure, one or more embodiments disclosed herein propose a solution through which failure-impacted network multicast(s) may be identified and, subsequently, restored with or without third-party intervention. To that end, one or more embodiments disclosed herein employ(s) a centralized network controller configured to obtain aggregated network state, including network topology information, through numerous logical agents interspersed across a network. Thereafter, the aggregated network state may be leveraged to ascertain and remedy any network multicast disruptions.

Abstract: A logical table is configured with a first set of memory banks, where each logical row in the logical table comprises a corresponding memory row from each of the memory banks. Lookup instructions to access a logical row includes a bank set that lists the memory banks associated with that logical row. In response to a range of memory rows of one of the memory banks being reallocated to another logical table, a new memory bank is identified to store the data in the reallocated memory rows. Logical rows associated with the reallocated memory rows are mapped to the new memory bank. Bank sets in the lookup instructions that refer to the remapped logical rows are updated to list the new memory bank in place of the “old” memory bank.

Abstract: In general, embodiments described herein relate to methods and systems for automating the configuration of network devices. More specifically, embodiments of the invention relate to using configuration commands that specify protocol-specified relationships in order to generate granular (or specific) filtering rules (also referred to as rules). The rules are subsequently programmed into the network device.