Abstract: A switch in a data network is configured to mediate data exchanges among network elements. The apparatus further includes a processor, which organizes the network elements into a hierarchical tree having a root node network element, vertex node network elements child node network elements that include leaf node network elements. The leaf node network elements are originate aggregation data and transmit the aggregation data to respective parent vertex node network elements. The vertex node network elements combine the aggregation data from at least a portion of the child node network elements, and transmit the combined aggregation data from the vertex node network elements to parent vertex node network elements. The root node network element is operative for initiating a reduction operation on the aggregation data.

Abstract: A method for communication, includes routing unicast data packets among nodes in a network using respective Layer-3 addresses that are uniquely assigned to each of the nodes. Respective Layer-2 unicast addresses are assigned to the nodes in accordance with an algorithmic mapping of the respective Layer-3 addresses. The unicast data packets are forwarded within subnets of the network using the assigned Layer-2 addresses.

Abstract: Methods and systems are disclosed for network congestion management. The methods and systems receive a first packet complying with a first network protocol comprising a first congestion indicator representative of a presence or absence of network congestion and further comprising a first set of data associated with a second network protocol, and provide an indication of the presence or absence of network congestion generated based, at least in part, on the first congestion indicator. The methods and systems also receive a first packet complying with a first network protocol comprising a first set of data associated with a second network protocol, and output a second packet complying with the first network protocol comprising a first congestion indicator representative of a presence of network congestion.

Abstract: A method in a network element that includes multiple interfaces for connecting to a communication network includes receiving from the communication network via an ingress interface a flow including a sequence of packets, and routing the packets to a destination of the flow via a first egress interface. A permission indication for re-routing the flow is received in the ingress interface. In response to receiving the permission indication, subsequent packets of the flow are re-routed via a second egress interface that is different from the first egress interface. Further re-routing of the flow is refrained from, until receiving another permission indication.

Abstract: Communication apparatus includes multiple interfaces configured for connection to a packet data network. A memory, coupled to the interfaces, is configured as a shared buffer to contain packets in multiple sets of queues for transmission to the network. Each set of queues receives in the shared buffer a respective allocation having an allocation size that varies over time in response to an amount of space in the shared buffer that is unused at any given time. A controller is configured to apply congestion control to a respective fraction of the packets that are queued for transmission from each set of queues in the shared buffer to the network, such that the respective fraction is set for each set of queues at any given time in response to a relation between a length of the queues in the set and the allocation size of the respective allocation at the given time.

Abstract: A method for communication includes configuring a router to forward data packets in a network in accordance with MPLS labels appended to the packets. A group of two or more of the interfaces is defined as a multi-path routing group in a forwarding table within the router. A plurality of records are stored in an ILM in the router, corresponding to different, respective label IDs, all pointing to the set of the entries in the forwarding table that belong to the multi-path routing group. Upon receiving in the router an incoming data packet having a label ID corresponding to any given record in the plurality, one of the interfaces in the group is selected, responsively to the given record and to the set of the entries in the forwarding table to which the given record points, for forwarding the incoming data packet without changing the label ID.

Abstract: A switching apparatus includes multiple ports, each including a respective buffer, and a switch controller. The switch controller is configured to concatenate the buffers of at least an input port and an output port selected from among the multiple ports for buffering traffic of a long-haul link, which is connected to the input port and whose delay exceeds buffering capacity of the buffer of the input port alone, and to carry out end-to-end flow control for the long haul link between the output port and the input port.

Abstract: An apparatus includes a bank of optical detectors, an input optical filter and a selector. The optical detectors are configured to output respective detection indications in response to detecting a presence of an optical signal. The input optical filter is configured to receive an input optical signal having an input wavelength, and to route the input optical signal to one of the optical detectors in the bank depending on the input wavelength. The selector is configured to select an output wavelength based on the detection indications of the optical detectors, and to cause generation and transmission of an output optical signal at the selected output wavelength.

Abstract: A communication network includes multiple nodes, which are arranged in groups such that the nodes in each group are interconnected in a bipartite topology and the groups are interconnected in a mesh topology. The nodes are configured to convey traffic between source hosts and respective destination hosts by routing packets among the nodes on paths that do not traverse any intermediate hosts other than the source and destination hosts.

Abstract: A network element includes circuitry and one or more interfaces. The interfaces are configured to connect to a communication network. The circuitry is configured to assign multiple egress interfaces corresponding to respective different paths via the communication network for routing packets to a given destination-address group, to hold, for the given destination-address group, respective state information for each of multiple sets of hash results, to receive via an ingress interface a packet destined to the given destination-address group, to calculate a given hash result for the packet and identify a given set of hash results in which the given hash result falls, and to forward the packet via one of the multiple egress interfaces in accordance with the state information corresponding to the given destination-address group and the given set of hash results.

Abstract: A method in a network element that includes multiple interfaces for connecting to a communication network includes receiving via an ingress interface packets that are not allowed to undergo re-routing and that are addressed to a destination via a first egress interface. The packets are forwarded via the first egress interface when there is a valid path from the first egress interface to the destination. When there is no valid path from the first egress interface to the destination, a second egress interface is selected from a group of multiple egress interfaces that have respective paths to the destination and are assigned to packets for which re-routing is allowed, and the packets are forwarded via the second egress interface until recovering a path to the destination.

Abstract: A switching apparatus includes multiple ports, each including a respective buffer, and a switch controller. The switch controller is configured to concatenate the buffers of at least an input port and an output port selected from among the multiple ports for buffering traffic of a long-haul link, which is connected to the input port and whose delay exceeds buffering capacity of the buffer of the input port alone, and to carry out end-to-end flow control for the long haul link between the output port and the input port.

Abstract: A method in a network element includes processing input packets using a set of two or more functions that are defined over parameters of the input packets. Each function in the set produces respective interim actions applied to the input packets and the entire set produces respective end-to-end actions applied to the input packets. An end-to-end mapping, which maps the parameters of at least some of the input packets directly to the corresponding end-to-end actions, is cached in the network element. The end-to-end mapping is queried with the parameters of a new input packet. Upon finding the parameters of the new input packet in the end-to-end mapping, an end-to-end action mapped to the found parameters is applied to the new input packet, without processing the new input packet using the set of functions.

Abstract: A method for communication, includes routing unicast data packets among nodes in a network using respective Layer-3 addresses that are uniquely assigned to each of the nodes. Respective Layer-2 unicast addresses are assigned to the nodes in accordance with an algorithmic mapping of the respective Layer-3 addresses. The unicast data packets are forwarded within subnets of the network using the assigned Layer-2 addresses.

Abstract: A system and method for accelerating input/output (IO) access operation on a virtual machine, The method comprises providing a smart IO device that includes an unrestricted command queue (CQ) and a plurality of restricted CQs and allowing a guest domain to directly configure and control IO resources through a respective restricted CQ, the IO resources allocated to the guest domain. In preferred embodiments, the allocation of IO resources to each guest domain is performed by a privileged virtual switching element. In some embodiments, the smart IO device is a HCA and the privileged virtual switching element is a Hypervisor.

Abstract: An apparatus includes a bank of optical detectors, an input optical filter and a selector. The optical detectors are configured to output respective detection indications in response to detecting a presence of an optical signal. The input optical filter is configured to receive an input optical signal having an input wavelength, and to route the input optical signal to one of the optical detectors in the bank depending on the input wavelength. The selector is configured to select an output wavelength based on the detection indications of the optical detectors, and to cause generation and transmission of an output optical signal at the selected output wavelength.

Abstract: Communication apparatus includes a switch, which includes switching logic, multiple ports for connection to a network, and a management port, and which is configured to assign both a first link-layer address and a second link-layer address to the management port. A host processor includes a memory and a central processing unit (CPU), which is configured to run software implementing a management agent for managing functions of the switch. A network interface controller (NIC) is connected to the management port and is configured to convey incoming management packets, which are directed by the switch to the first link-layer address, to the CPU for processing by the management agent, and to write directly to the memory data contained in incoming remote direct memory access (RDMA) packets, which are directed by the switch to the second link-layer address.

Abstract: A method of implementing a logical unit reset across a plurality of interfaces in a distributed storage system, comprising: initiating a session for implementing the logical unit reset across the plurality of interfaces in response to receiving at a central controller a logical unit reset command from an originator interface, and writing session-data including an indication that the originator interface implemented the respective logical unit reset locally; communicating a logical unit reset command from the central controller to each interface other than the originator interface; updating the session data in response to receiving an indication from an interface that the logical unit was successfully reset locally and when each one of the plurality of interfaces implemented the logical unit reset locally, communicating a success response to each one of the plurality of interfaces.

Abstract: According to an aspect of the presently disclosed subject matter, there is provided a system for managing data in a storage system, the system including a storage layer which provides storage resource, and a snapshot layer that includes: a volume-version data structure, a chunk-version data structure and a IO handler.

Abstract: Methods and systems are disclosed for network congestion management. The methods and systems receive a first packet complying with a first network protocol comprising a first congestion indicator representative of a presence or absence of network congestion and further comprising a first set of data associated with a second network protocol, and provide an indication of the presence or absence of network congestion generated based, at least in part, on the first congestion indicator. The methods and systems also receive a first packet complying with a first network protocol comprising a first set of data associated with a second network protocol, and output a second packet complying with the first network protocol comprising a first congestion indicator representative of a presence of network congestion.