Abstract: A method for transmitting MAC frames between remote and/or virtual machines, across network devices (i.e., switches, multilayer switches, and routers) that conventionally do not hold capacity to address MAC rewrites to any and all possible destinations within expanding data centers. More specifically, a network device retains MAC rewrite table entries corresponding to Top of Rack (ToR) switches versus to the hosts and virtual machines that reside under those ToR switches. This use of a ToR switch as an overlay routing intermediate point may reduce the number of required MAC addresses stored on a network device for the purposes of performing rewrites, thereby once again establishing the capability for packets to reach any arbitrary destination as data centers scale.

Abstract: A method and apparatus of a device that determines a match for a destination address using an exact match table and a longest prefix match table of a network element is described. In an exemplary embodiment, the network element receives a data packet that includes a destination address. The network element generates a key for the destination address, wherein the key represents more addresses than the destination address. The network element further performs an address lookup using the key in an exact match table. Furthermore, a match in the address lookup indicates a first transmitting interface of the network element. The network element additionally performs an address lookup using the destination address with a longest prefix match table, wherein a match in the address lookup indicates a second transmitting interface of the network element.

Abstract: A method and apparatus of a network element that installs a control plane data rule from system memory to specialized hardware memory in a network element is described. In an exemplary embodiment, the network element receives control plane data processing statistics of control plane data that is received by the network element, where the control plane data is policed using a plurality of control plane data policing rules stored in the system memory. The network element further determines that a candidate policing rule is being utilized greater than a threshold based on at least the control plane data processing statistics, where the candidate policing rule is one of the plurality of control plane data policing rules stored in the system memory. The network element additionally installs the candidate policing rule in the specialized hardware memory, where the candidate policing rule is subsequently used by the network element to police the control plane data.

Abstract: A method and apparatus of a device that includes a shared memory hash table that notifies one or more readers of changes to the shared memory hash table is described. In an exemplary embodiment, a device modifies a value in the shared memory hash table, where the value has a corresponding key. The device further stores a notification in a notification queue that indicates the value has changed. In addition, the device invalidates a previous entry in the notification queue that indicates the value has been modified. The device signals to the reader that a notification is ready to be processed.

Abstract: A method and apparatus of a device that determines a match for a destination address using an exact match table and a longest prefix match table of a network element is described. In an exemplary embodiment, the network element receives a data packet that includes a destination address. The network element generates a key for the destination address, wherein the key represents more addresses than the destination address. The network element further performs an address lookup using the key in an exact match table. Furthermore, a match in the address lookup indicates a first transmitting interface of the network element. The network element additionally performs an address lookup using the destination address with a longest prefix match table, wherein a match in the address lookup indicates a second transmitting interface of the network element.

Abstract: A method and apparatus of a device that determines a match for a destination address using an exact match table and a longest prefix match table of a network element is described. In an exemplary embodiment, the network element receives a data packet that includes a destination address. The network element generates a key for the destination address, wherein the key represents more addresses than the destination address. The network element further performs an address lookup using the key in an exact match table. Furthermore, a match in the address lookup indicates a first transmitting interface of the network element. The network element additionally performs an address lookup using the destination address with a longest prefix match table, wherein a match in the address lookup indicates a second transmitting interface of the network element.

Abstract: A method and apparatus of a device that determines a cause and effect of congestion in this device is described. In an exemplary embodiment, the device measures a queue group occupancy of a queue group for a port in the device, where the queue group stores a plurality of packets to be communicated through that port. In addition, the device determines if the measurement indicates a potential congestion of the queue group, where the congestion prevents a packet from being communicated within a time period. If potential congestion exists on that queue group, the device further gathers information regarding packets to be transmitted through that port. For example, the device can gather statistics packets that are stored in the queue group and/or new enqueue packets.

Abstract: A method and apparatus of a network element that processes a packet in the network element is described. In an exemplary embodiment, the network element receives a data packet that includes a destination address. The network element receives a packet, with a packet switch unit, wherein the packet was received by the network element on an ingress interface. The network element further determines if the packet is to be stored in an external queue. In addition, the network element identifies the external queue for the packet based on one or more characteristics of the packet. The network element additionally forwards the packet to a packet storage unit, wherein the packet storage unit includes storage for the external queue. Furthermore, the network element receives the packet from the packet storage unit and forwards the packet to an egress interface corresponding to the external queue.

Abstract: A method and apparatus of a device that broadcasts data to multiple hardware forwarding engines is described. In an exemplary embodiment, a central processing unit of the device receives the data to broadcast to the plurality of hardware forwarding engines. The device further writes the data to a broadcast log. In addition, the device transmits a signal to one or more co-processors that the data is available to be read, wherein each of the plurality of hardware forwarding corresponds to one of the one or more co-processors. Each of these co-processors reads the data in the broadcast log by receiving the signal that the data is ready to be read from the broadcast log. In addition, each co-processor determines a broadcast log entry for the data for that co-processor. Each co-processor further reads the data from the broadcast log entry via a direct memory access in memory that stores the broadcast log and the plurality of hardware forwarding engines use the data to process network traffic.

Abstract: A method and apparatus of a device that determines a cause and effect of congestion in this device is described. The device determines an effect of congestion in the device. The device measures a queue group occupancy of a queue group for a port in the device, where the queue group stores a plurality of packets to be communicated through that port. The device further determines if congestion exists on that queue group using the measurement, where the congestion prevents a packet of the plurality of packets from being communicated within a time period. If the congestion exists on that queue group, the device additionally gathers information regarding packets to be transmitted through that port. For example, the device can gather statistics packets that are stored in the queue group and/or new enqueue packets.

Abstract: A method and apparatus of a device that determines a cause and effect of congestion in this device is described. In an exemplary embodiment, the device measures a queue group occupancy of a queue group for a port in the device, where the queue group stores a plurality of packets to be communicated through that port. In addition, the device determines if the measurement indicates a potential congestion of the queue group, where the congestion prevents a packet from being communicated within a time period. If potential congestion exists on that queue group, the device further gathers information regarding packets to be transmitted through that port. For example, the device can gather statistics packets that are stored in the queue group and/or new enqueue packets.

Abstract: A method and apparatus of a device that determines a match for a destination address using an exact match table and a longest prefix match table of a network element is described. In an exemplary embodiment, the network element receives a data packet that includes a destination address. The network element generates a key for the destination address, wherein the key represents more addresses than the destination address. The network element further performs an address lookup using the key in an exact match table. Furthermore, a match in the address lookup indicates a first transmitting interface of the network element. The network element additionally performs an address lookup using the destination address with a longest prefix match table, wherein a match in the address lookup indicates a second transmitting interface of the network element.

Abstract: A method and apparatus of a device that determines a match for a destination address using an exact match table and a longest prefix match table of a network element is described. In an exemplary embodiment, the network element receives a data packet that includes a destination address. The network element generates a key for the destination address, wherein the key represents more addresses than the destination address. The network element further performs an address lookup using the key in an exact match table. Furthermore, a match in the address lookup indicates a first transmitting interface of the network element. The network element additionally performs an address lookup using the destination address with a longest prefix match table, wherein a match in the address lookup indicates a second transmitting interface of the network element.

Abstract: A method and apparatus of a device that updates a key range in a database for a writer of a network element that replicates changes to the database to a plurality of readers. In an exemplary embodiment, the device receives a key deletion notification for a key, where the key deletion notification is a notification to delete a key from the database and the database stores data used by the network element. The device further locates the key in an ordered data structure, the ordered data structure stores a plurality of keys in an ordered fashion. The device additionally deletes the in the ordered data structure and determines an upper and lower bound key for the deleted key. In addition, the device creates an empty key range from the upper and lower bound keys and creates an empty key range notification from the empty key range.

Abstract: A method and apparatus of a device that determines a match for a destination address using an exact match table and a longest prefix match table of a network element is described. In an exemplary embodiment, the network element receives a data packet that includes a destination address. The network element generates a key for the destination address, wherein the key represents more addresses than the destination address. The network element further performs an address lookup using the key in an exact match table. Furthermore, a match in the address lookup indicates a first transmitting interface of the network element. The network element additionally performs an address lookup using the destination address with a longest prefix match table, wherein a match in the address lookup indicates a second transmitting interface of the network element.

Abstract: Embodiments for communicating packets with a first port of a network element without the first port being communicatively coupled to another device (e.g., testing equipment) are described. In one embodiment, a packet is generated by testing equipment that is communicatively coupled to a second port of the network element. The packet includes a tag that uniquely identifies the first port. The network element communicates the packet from the second port to the first port based on the tag. The network element also removes the tag from the packet. The removal can occur before the packet is received at the first port or after the packet is received at an ingress module of the first port. In response to the removal of the tag, the network element enters the first port into a loopback mode that is internal to the first port.

Abstract: Improved utilization of connections that can be either available or blocked is provided by associating an atemporal connection state with each connection. If a connection is available, messages are transmitted on the connection normally. If a connection is blocked, the atemporal connection state is updated to reflect the changes that were made but not transmitted. In this manner, a record is kept that allows correct transmission of the information when the connection comes back up. More specifically, after a connection status changes from blocked to available, recovery messages are automatically generated from the atemporal connection state and transmitted on the connection.

Abstract: A method and apparatus of a device that uses a hardware shadow for a central processing unit failover is described. In an exemplary embodiment, a device receives a signal that the active central processing unit has failed, where the active central processing unit controls the processing functions of the network element and the network element includes a hardware forwarding engine and a hardware shadow. The hardware shadow additionally includes multiple shadow tables. For each shadow table, the device copies data from that shadow table to a corresponding table in the hardware forwarding engine, where the hardware shadow is a copy of the data stored in hardware tables for the hardware forwarding engine. In response to the copying, the device further switches control of the network element processing functions from the active central processing unit to a standby central processing unit.

Abstract: A method and apparatus of a network element that authenticates a transceiver and/or a field replaceable unit of the network element is described. The network element generates a stored transceiver signature using transceiver data stored in the removable transceiver and a nonce. In addition, the network element generates a hardware transceiver signature using data stored in secure storage of the network element and the nonce. If the stored transceiver signature and the hardware transceiver signature are equal, the network element uses the transceiver to communicate network data for the network element. Otherwise, the network element disables the transceiver.

Abstract: A method and apparatus of a device that broadcasts data to multiple hardware forwarding engines is described. In an exemplary embodiment, a central processing unit of the device receives the data to broadcast to the plurality of hardware forwarding engines. The device further writes the data to a broadcast log. In addition, the device transmits a signal to one or more co-processors that the data is available to be read, wherein each of the plurality of hardware forwarding corresponds to one of the one or more co-processors. Each of these co-processors reads the data in the broadcast log by receiving the signal that the data is ready to be read from the broadcast log. In addition, each co-processor determines a broadcast log entry for the data for that co-processor. Each co-processor further reads the data from the broadcast log entry via a direct memory access in memory that stores the broadcast log and the plurality of hardware forwarding engines use the data to process network traffic.