Abstract: Network access node virtual fabrics configured dynamically over an underlay network are described. A centralized controller, such as a software-defined networking (SDN) controller, of a packet switched network is configured to establish one or more virtual fabrics as overlay networks on top of the physical underlay network of the packet switched network. For example, the SDN controller may define multiple sets of two of more access nodes connected to the packet switched network, and the access nodes of a given one of the sets may use a new data transmission protocol, referred to generally herein as a fabric control protocol (FCP), to dynamically setup tunnels as a virtual fabric over the packet switched network. The FCP tunnels may include all or a subset of the parallel data paths through the packet switched network between the access nodes for a given virtual fabric.

Abstract: A network system for a data center is described in which a switch fabric may provide full mesh interconnectivity such that any servers may communicate packet data to any other of the servers using any of a number of parallel data paths. Moreover, according to the techniques described herein, edge-positioned access nodes, optical permutation devices and core switches of the switch fabric may be configured and arranged in a way such that the parallel data paths provide single L2/L3 hop, full mesh interconnections between any pairwise combination of the access nodes, even in massive data centers having tens of thousands of servers. The plurality of optical permutation devices permute communications across the optical ports based on wavelength so as to provide, in some cases, full-mesh optical connectivity between edge-facing ports and core-facing ports.

Abstract: Techniques for detecting path failures and reducing packet loss as a result of such failures are described for use within a data center or other environment. For example, a source and/or destination access node may create and/or maintain information about health and/or connectivity for a plurality of ports or paths between the source and destination device and core switches. The source access node may spray packets over a number of paths between the source access node and the destination access node. The source access node may use the information about connectivity for the paths between the source or destination access nodes and the core switches to limit the paths over which packets are sprayed. The source access node may spray packets over paths between the source access node and the destination access node that are identified as healthy, while avoiding paths that have been identified as failed.

Abstract: This disclosure describes techniques that include storing, during parsing of a data unit or a network packet, information (i.e., “summary information”) that identifies how the network packet has been process and/or other aspects of the parsing process. In one example, this disclosure describes a method that includes parsing a packet header from a data unit, wherein parsing the packet header includes storing in result vector storage each of a plurality of data items derived from the packet header, the result vector storage having a result vector format defining fields within the result vector storage for storing each of the plurality of data items; storing in template storage, for each of the plurality of data items, summary information about the plurality of data items stored in the result vector storage; and processing, by the packet-processing integrated circuit and based on the summary information and the plurality of data items, the network packet.

Abstract: Network access node virtual fabrics configured dynamically over an underlay network are described. A centralized controller, such as a software-defined networking (SDN) controller, of a packet switched network is configured to establish one or more virtual fabrics as overlay networks on top of the physical underlay network of the packet switched network. For example, the SDN controller may define multiple sets of two of more access nodes connected to the packet switched network, and the access nodes of a given one of the sets may use a new data transmission protocol, referred to generally herein as a fabric control protocol (FCP), to dynamically setup tunnels as a virtual fabric over the packet switched network. The FCP tunnels may include all or a subset of the parallel data paths through the packet switched network between the access nodes for a given virtual fabric.

Abstract: This disclosure describes techniques for performing communications between devices using various aspects of Ethernet standards. As further described herein, a protocol is disclosed that may be used for communications between devices, where the communications take place over a physical connection complying with Ethernet standards. Such a protocol may enable reliable and in-order delivery of frames between devices, while following Ethernet physical layer rules, Ethernet symbol encoding, Ethernet lane alignment, and/or Ethernet frame formats.

Abstract: A new processing architecture is described that utilizes a data processing unit (DPU). Unlike conventional compute models that are centered around a central processing unit (CPU), the DPU that is designed for a data-centric computing model in which the data processing tasks are centered around the DPU. The DPU may be viewed as a highly programmable, high-performance I/O and data-processing hub designed to aggregate and process network and storage I/O to and from other devices. The DPU comprises a network interface to connect to a network, one or more host interfaces to connect to one or more application processors or storage devices, and a multi-core processor with two or more processing cores executing a run-to-completion data plane operating system and one or more processing cores executing a multi-tasking control plane operating system. The data plane operating system is configured to support software functions for performing the data processing tasks.

Abstract: This disclosure describes techniques for addressing and/or accounting for path failures (e.g., congestion, link failures, disconnections, or other types of failures) within a network environment. In one example, this disclosure describes a method that includes receiving, by a node connected to a plurality of interconnected nodes, a network packet to be forwarded to a destination node; identifying, by a forwarding plane within the node, a first link along a path to the destination node; determining, by the forwarding plane, that the first link is inoperable; storing, by the node and within the network packet, data identifying the node as having been visited; identifying, by the forwarding plane and from among the plurality of egress links from the node, a second link that is operable and is along an alternative path to the destination node; and transmitting the network packet over the second link.

Abstract: This disclosure describes techniques for performing communications between devices using various aspects of Ethernet standards. As further described herein, a protocol is disclosed that may be used for communications between devices, where the communications take place over a physical connection complying with Ethernet standards. Such a protocol may enable reliable and in-order delivery of frames between devices, while following Ethernet physical layer rules, Ethernet symbol encoding, Ethernet lane alignment, and/or Ethernet frame formats.

Abstract: A network system for a data center is described in which an access node sprays a data flow of packets over a logical tunnel to another access node. In one example, a method comprises establishing, by a plurality of access nodes, a logical tunnel over a plurality of data paths across a switch fabric between a source access node and a destination access node included within the plurality of access nodes, wherein the source access node is coupled to a source network device; and spraying, by the source access node, a data flow of packets over the logical tunnel to the destination access node, wherein the source access node receives the data flow of packets from the source network device, and wherein spraying the data flow of packets includes directing each of the packets within the data flow to a least loaded data path.

Abstract: The disclosure describes example techniques for determining a data rate at which destination blocks are to receive data unit on a communication mesh. The destination block may determine the data rate at which the destination block is to receive data unit and broadcast information indicative of the data rate on a congestion mesh. The congestion mesh may be configured to route the broadcasted information in a manner that accounts for the relative positions of the circuit blocks in the congestion mesh.

Abstract: This disclosure describes techniques that include associating a timestamp with a network packet, and carrying the timestamp or otherwise associating the timestamp with the network packet during some or all processing by the system described herein. In one example, this disclosure describes a method that includes receiving, at an ingress port of a device, an initial portion of a network packet; storing, by the device, timestamp information associated with receiving the initial portion of the packet; and determining, by the device, whether to transmit information derived from the initial portion of the network packet.

Abstract: An access node that can be configured and optimized to perform input and output (I/O) tasks, such as storage and retrieval of data to and from network devices (such as solid state drives), networking, data processing, and the like. For example, the access node may be configured to receive data to be processed, wherein the access node includes a plurality of processing cores, a data network fabric, and a control network fabric; receive, over the control network fabric, a work unit message indicating a processing task to be performed a processing core; and process the work unit message, wherein processing the work unit message includes retrieving data associated with the work unit message over the data network fabric.

Abstract: A network system for a data center is described in which a switch fabric provides interconnectivity such that any servers may communicate packet data to any other of the servers using any of a number of parallel data paths. Moreover, according to the techniques described herein, edge-positioned access nodes, permutation devices and core switches of the switch fabric may be configured and arranged in a way such that the parallel data paths provide single L2/L3 hop, full mesh interconnections between any pairwise combination of the access nodes, even in massive data centers having tens of thousands of servers. The access nodes may be arranged within access node groups, and permutation devices may be used within the access node groups to spray packets across the access node groups prior to injection within the switch fabric, thereby increasing the fanout and scalability of the network system.

Abstract: A new processing architecture is described that utilizes a data processing unit (DPU). Unlike conventional compute models that are centered around a central processing unit (CPU), the DPU that is designed for a data-centric computing model in which the data processing tasks are centered around the DPU. The DPU may be viewed as a highly programmable, high-performance I/O and data-processing hub designed to aggregate and process network and storage I/O to and from other devices. The DPU comprises a network interface to connect to a network, one or more host interfaces to connect to one or more application processors or storage devices, and a multi-core processor with two or more processing cores executing a run-to-completion data plane operating system and one or more processing cores executing a multi-tasking control plane operating system. The data plane operating system is configured to support software functions for performing the data processing tasks.

Abstract: A network system for a data center is described in which a switch fabric provides full mesh interconnectivity such that any servers may communicate packet data to any other of the servers using any of a number of parallel data paths. Moreover, according to the techniques described herein, edge-positioned access nodes, optical permutation devices and core switches of the switch fabric may be configured and arranged in a way such that the parallel data paths provide single L2/L3 hop, full mesh interconnections between any pairwise combination of the access nodes, even in massive data centers having tens of thousands of servers.

Abstract: A fabric control protocol is described for use within a data center in which a switch fabric provides full mesh interconnectivity such that any of the servers may communicate packet data for a given packet flow to any other of the servers using any of a number of parallel data paths within the data center switch fabric. The fabric control protocol enables spraying of individual packets for a given packet flow across some or all of the multiple parallel data paths in the data center switch fabric and, optionally, reordering of the packets for delivery to the destination. The fabric control protocol may provide end-to-end bandwidth scaling and flow fairness within a single tunnel based on endpoint-controlled requests and grants for flows. In some examples, the fabric control protocol packet structure is carried over an underlying protocol, such as the User Datagram Protocol (UDP).

Abstract: A highly-programmable access node is described that can be configured and optimized to perform input and output (I/O) tasks, such as storage and retrieval of data to and from storage devices (such as solid state drives), networking, data processing, and the like. For example, the access node may be configured to execute a large number of data I/O processing tasks relative to a number of instructions that are processed. The access node may be highly programmable such that the access node may expose hardware primitives for selecting and programmatically configuring data processing operations. As one example, the access node may be used to provide high-speed connectivity and I/O operations between and on behalf of computing devices and storage components of a network, such as for providing interconnectivity between those devices and a switch fabric of a data center.

Abstract: A network system for a data center is described in which a switch fabric provides full mesh interconnectivity such that any servers may communicate packet data to any other of the servers using any of a number of parallel data paths. Moreover, according to the techniques described herein, edge-positioned access nodes, permutation devices and core switches of the switch fabric may be configured and arranged in a way such that the parallel data paths provide single L2/L3 hop, full mesh interconnections between any pairwise combination of the access nodes, even in massive data centers having tens of thousands of servers. The access nodes may be arranged within access node groups, and permutation devices may be used within the access node groups to spray packets across the access node groups prior to injection within the switch fabric, thereby increasing the fanout and scalability of the network system.

Abstract: This disclosure describes techniques that include storing, during parsing of a data unit or a network packet, information (i.e., “summary information”) that identifies how the network packet has been process and/or other aspects of the parsing process. In one example, this disclosure describes a method that includes parsing a packet header from a data unit, wherein parsing the packet header includes storing in result vector storage each of a plurality of data items derived from the packet header, the result vector storage having a result vector format defining fields within the result vector storage for storing each of the plurality of data items; storing in template storage, for each of the plurality of data items, summary information about the plurality of data items stored in the result vector storage; and processing, by the packet-processing integrated circuit and based on the summary information and the plurality of data items, the network packet.