Abstract: Aspects of oversubscription monitoring are described. In one embodiment, oversubscription monitoring includes accumulating an amount of data that arrives at a network component over at least one epoch of time. Further, a core processing rate at which data can be processed by the network component is calculated. Based on the amount of data and the core processing rate, it is determined whether the network component is operating in an oversubscribed region of operation. In one embodiment, when the network component is operating in the oversubscribed region of operation, certain quality of service metrics are monitored. Using the monitored metrics, a network operation display object may be generated for identifying or troubleshooting network errors during an oversubscribed region of operation of the network component.

Abstract: A data segment of a data packet destined for an egress port of an egress node may be received at a first ingress node. An egress statement vector and an ingress statement vector may be identified at the first ingress node. A determination may be made, based on the egress statement vector and ingress statement vector, whether the first ingress node is authorized to transfer the data segment to the egress port before the other data segments of the data packet are received at the first ingress node. The data segment may be transferred to the egress port before the other data segments of the data packet are received at the first ingress node when the determination indicates the first ingress node is authorized. The data segment may be stored in a buffer of the first ingress node when the determination indicates the first ingress node is not authorized.

Abstract: A system and method to monitor network congestion is provided. The system includes a plurality of ingress, egress ports, and a plurality of queues coupled to the ingress and egress ports and configured to store incoming and outgoing packets. The system also includes a monitoring unit configured to monitor at least one attribute of packets in at least one queue when a start condition occurs, stop monitoring the attribute when an end condition occurs, determine a flow that caused the start condition based on the monitored attribute, and report the monitored attribute and the flow.

Abstract: Disclosed are various embodiments that relate identifying a source of corruption in a network made up of multiple network nodes. A network node is configured to provide corruption source identification while handling packets according to a cut-through scheme. According to some embodiments, a network node may perform a running error detection operation on a cut-through packet and then insert a debug indicator into the cut through packet. In other embodiments, the network node may process some packets according to a cut-through scheme while process other packets according to a store-and-forward scheme to detect packet corruption in a network.

Abstract: A system transfers data. The system includes an ingress node transferring data at a determined bandwidth. The ingress node includes a buffer and operates based on a monitored node parameter. The system includes a controller in communication with the ingress node. The controller is configured to allocate, based on the monitored node parameter, an amount of the determined bandwidth for directly transferring data to bypass the buffer of the ingress node.

Abstract: According to one general aspect, a method may include, in one embodiment, grouping a plurality of at least single-ported memory banks together to substantially act as a single at least dual-ported aggregated memory element. In various embodiments, the method may also include controlling read access to the memory banks such that a read operation may occur from any memory bank in which data is stored. In some embodiments, the method may include controlling write access to the memory banks such that a write operation may occur to any memory bank which is not being accessed by a read operation.

Abstract: A network device performs ingress based headroom buffering. The network device may be configured as an output queue switch and include a main packet buffer that stores packet data according to a destination egress port. The network device may implement one or more ingress buffers associated with ingress data ports in the network device. The ingress buffers may be separate from the main packet buffer. The network device may identify a flow control condition triggered by an ingress data port, such as when an amount of data stored in the main packet buffer received through the ingress data port exceeds a fill threshold. In response, the network device may send a flow control message to a link partner to cease sending network traffic through the ingress data port. The network device may store in-flight data from the link partner in an ingress buffer instead of the main packet buffer.

Abstract: Disclosed are various embodiments that provide an architecture of memory buffers for a network component configured to process packets. A network component may receive a packet, the packet being associated with a control structure and packet data, an input port set and an output port set. The network component determines one of a plurality of control structure memory partitions for writing the control structure, the one of the plurality of control structure memory partitions being determined based at least upon the input port set and the output port set; and determines one of a plurality of packet data memory partitions for writing the packet data, the one of the plurality of packet data memory partitions being determined independently of the input port set.

Abstract: A system and method for system and method for efficient buffer management for banked shared memory designs. In one embodiment, a controller within the switch is configured to manage the buffering of the shared memory banks by allocating full address sets to write sources. Each full address set that is allocated to a write source includes a number of memory addresses, wherein each memory address is associated with a different shared memory bank. A size of the full address set can be based on a determined number of buffer access contenders.

Abstract: Various example embodiments are disclosed. According to an example embodiment, an apparatus may include a switch fabric. The switch fabric may be configured to assign packets to either a first flow set or a second flow set based on fields included in the packets. The switch fabric may also be configured to send a first packet from the first flow set to a first flow set destination via a first path. The switch fabric may also be configured to determine, based at least in part on delays of the first path and a second path, whether sending a second packet from the first flow set to the first flow set destination via a second path will result in the second packet reaching the first flow set destination after the first packet reaches the first flow set destination, the second packet having been received by the router after the first packet.

Abstract: The systems and methods described herein allow for the scaling of output-buffered switches by decoupling the data path from the control path. Some embodiment of the invention include a switch with a memory management unit (MMU), in which the MMU enqueues data packets to an egress queue at a rate that is less than the maximum ingress rate of the switch. Other embodiments include switches that employ pre-enqueue work queues, with an arbiter that selects a data packet for forwarding from one of the pre-enqueue work queues to an egress queue.

Abstract: Processing techniques in a network switch help reduce latency in the delivery of data packets to a recipient. The processing techniques include speculative flow status messaging, for example. The speculative flow status messaging may alert an egress tile or output port of an incoming packet before the incoming packet is fully received. The processing techniques may also include implementing a separate accelerated credit pool which provides controlled push capability for the ingress tile or input port to send packets to the egress tile or output port without waiting for a bandwidth credit from the egress tile or output port.

Abstract: Disclosed are various embodiments for improving hash table utilization. A key corresponding to a data item to be inserted into a hash table can be transformed to improve the entropy of the key space and the resultant hash codes that can generated. Transformation data can be inserted into the key in various ways, which can result in a greater degree of variance in the resultant hash code calculated based upon the transformed key.

Abstract: Systems and methods for dynamically adjusting the gain in a receiver front end. The gain is adjusted in order to make an error margin for each incoming signal essentially equal. Signals are initially received together. The signals are split in order to allow for independent adjustments to the gain of each signal. The signals are then gain adjusted. After gain adjustments are made, the signals are recombined.

Abstract: A system and method for achieving lossless packet delivery in packet rate oversubscribed systems. Link-level packet rate control can be effected through the transmission of packet rate control messages to link partners of an oversubscribed system. The transmission of packet rate control messages can be triggered upon a determination that a packet arrival rate over a set of ingress ports exceeds a packet processing rate of a packet processing unit bound to the set of ingress ports. In one embodiment, the packet processing rate is artificially reduced due to a reduction in power consumption in the oversubscribed system.

Abstract: Disclosed are various embodiments for facilitating network flows in a networked environment. In various embodiments, a switch transmits data using an egress port that comprises an egress queue. The switch sets a congestion notification threshold for the egress queue. The switch generates a drain rate metric based at least in part on a drain rate for the egress queue, and the congestion notification threshold is adjusted based at least in part on the drain rate metric.

Abstract: Methods and apparatus for dynamic load balancing using virtual link credit accounting are disclosed. An example method includes receiving, at a network device, a data packet to be communicated using an aggregation group, the aggregation group including a plurality of virtual links having a common destination. The example method further includes determining a hash value based on the packet and determining an assigned virtual link of the plurality of virtual links based on the hash value. The example method also includes reducing a number of available transmission credits for the aggregation group and reducing a number of available transmission credits for the assigned virtual link. The example method still further includes communicating the packet to another network device using the assigned virtual link.

Abstract: A network device identifies elephant flows. The network device filters received network data according to an application-specific criteria and identifies the elephant flow from the filtered network data. To do so, the network device can employ a multi-stage filtering process to identify an elephant flow in the received network data. The network device separates the filtered network data into multiple macroflows using a first hash function, and identifies the macroflow with the highest rate. Then, the network device disaggregates the high rate macroflow into multiple microflows using a second hash function and identifies the highest rate microflow as the elephant flow. The network device maintains an elephant flow cache with entries for currently identified elephant flows. The network device may also take management actions on the elephant flows, and the management actions may be application specific.