Abstract: A method includes receiving in a network switch of a communication network communication traffic that originates from a source node and arrives over a route through the communication network traversing one or more preceding network switches, for forwarding to a destination node. In response to detecting in the network switch a compromised ability to forward the communication traffic to the destination node, a notification is sent to the preceding network switches. The notification is to be consumed by the preceding network switches and requests the preceding network switches to modify the route so as not to traverse the network switch.

Abstract: A method for communication in a packet data network including a subnet containing multiple nodes having respective ports. The method includes assigning respective local identifiers to the ports in the subnet, such that each port receives a respective local identifier that is unique within the subnet to serve as an address for traffic within the subnet that is directed to the port. In addition to the local identifiers, respective port identifiers are assigned to the ports, such that at least one of the port identifiers is shared by a plurality of the ports, but not by all the ports, in the subnet. The plurality of the ports are addressed collectively using the at least one of the port identifiers.

Abstract: A method for communication in a packet data network that includes at least first and second subnets interconnected by multiple routers and having respective first and second subnet managers. The method includes assigning respective local identifiers to ports for addressing of data link traffic within each subnet, such that the first subnet manager assigns the local identifiers in the first subnet, and the second subnet manager assigns the local identifiers in the second subnet. The routers are configured by transmitting and receiving control traffic between the subnet managers and the routers. Data packets are transmitted between network nodes in the first and second subnets via one or more of the configured routers under control of the subnet managers.

Abstract: A network interface device for a host computer includes a network interface, configured to transmit and receive data packets to and from a network. Packet processing logic transfers data to and from the data packets transmitted and received via the network interface by direct memory access (DMA) from and to a system memory of the host computer. A memory controller includes a first memory interface configured to be connected to the system memory and a second memory interface, configured to be connected to a host complex of the host computer. Switching logic alternately couples the first memory interface to the packet processing logic in a DMA configuration and to the second memory interface in a pass-through configuration.

Abstract: A network interface adapter includes a network interface and a client interface, for coupling to a client device so as to receive from the client device work requests to send messages over the network using a plurality of transport service instances. Message processing circuitry, coupled between the network interface and the client interface, includes an execution unit, which generates the messages in response to the work requests and passes the messages to the network interface to be sent over the network. A memory stores records of the messages that have been generated by the execution unit in respective lists according to the transport service instances with which the messages are associated. A completion unit receives the records from the memory and, responsive thereto, reports to the client device upon completion of the messages.

Abstract: A communication apparatus includes a plurality of switch ports, each switch port including one or more port buffers for buffering data that traverses the switch port. A switch fabric is coupled to transfer the data between the switch ports. A switch control unit is configured to reassign at least one port buffer of a given switch port to buffer a part of the data that does not enter or exit the apparatus via the given switch port, and to cause the switch fabric to forward the part of the data to a destination switch port via the at least one reassigned port buffer.

Abstract: A method for communication includes routing a first packet, which belongs to a given packet flow, over a first routing path through a communication network. A second packet, which follows the first packet in the given packet flow, is routed using a time-bounded Adaptive Routing (AR) mode, by evaluating a time gap between the first and second packets, routing the second packet over the first routing path if the time gap does not exceed a predefined threshold, and, if the time gap exceeds the predefined threshold, selecting a second routing path through the communication network that is potentially different from the first routing path, and routing the second packet over the second routing path.

Abstract: A method for communication includes allocating in a memory of a host device a contiguous, cyclical set of buffers for use by a transport service instance on a network interface controller (NIC). First and second indices point respectively to a first buffer in the set to which the NIC is to write and a second buffer in the set from which a client process running on the host device is to read. Upon receiving at the NIC a message directed to the transport service instance and containing data to be pushed to the memory, the data are written to the first buffer that is pointed to by the first index, and the first index is advanced cyclically through the set. The second index is advanced cyclically through the set when the data in the second buffer have been read by the client process.

Abstract: A method for communication includes sending a pause frame from a first node to a second node over a communication link between the nodes. In response to the pause frame, one or more data frames are immediately transmitted from the second node to the first node upon receipt of the pause frame at the second node.

Abstract: A network interface adapter provides a host processor with two complementary modes of submitting descriptors to be executed by the adapter: a normal mode, in which the host writes descriptors to a system memory and rings an assigned doorbell to notify the adapter; and a priority mode, in which the host writes the descriptor itself to a doorbell address of the adapter. In the priority mode, the adapter is relieved of the need to read the descriptor from the memory, and can thus begin execution as soon as it has resources available to do so.

Abstract: A communication method in a network operating in accordance with a standard that allocates a given number of bits m for layer-2 addressing of nodes in the network. The method includes accepting at a layer-2 switch in the network an assignment to one or more nodes in the network of respective layer-2 extended addresses, each including n=m+k bits, k>0. A given data packet is received at the switch for forwarding. The given data packet includes a layer-2 destination address and a layer-3 destination address in accordance with the standard. The layer-3 destination address includes t bits, t?k. The given data packet is forwarded from the switch to one of the nodes by reading from the given data packet and combining the layer-2 destination address and k bits from the layer-3 destination address so as to reconstruct the n bits of the extended layer-2 address of the one of the nodes.

Abstract: An input/output (I/O) device includes a host interface for connection to a host device having a memory and a network interface, which is configured to receive, over a network, data packets associated with I/O operations directed to specified virtual addresses in the memory. Packet processing hardware is configured to translate the virtual addresses into physical addresses and to perform the I/O operations using the physical addresses, and upon an occurrence of a page fault in translating one of the virtual addresses, to transmit a response packet over the network to a source of the data packets so as to cause the source to refrain from transmitting further data packets while the page fault is serviced.

Abstract: A method of communication includes receiving, in a network interface device, first and second requests from an initiator process running on an initiator host to transmit, respectively, first and second data to first and second target processes running on one or more target nodes, via a packet network. A single dynamically-connected initiator context is allocated for serving both the first and second requests. A first connect packet referencing the dynamically-connected (DC) initiator context is directed to the first target process so as to open a first dynamic connection with the first target process, followed by transmission of the first data over the first dynamic connection. The first dynamic connection is closed after the transmission of the first data, and a second connect packet is transmitted so as to open a second dynamic connection with the second target process, followed by transmission of the second data.

Abstract: A method for communication includes receiving a packet at a first node for transmission over a link to a second node. The data in the packet is divided into a sequence of cells of a predetermined data size. The cells have respective sequence numbers. The cells are transmitted in sequence over the link, while storing the transmitted cells in a buffer at the first node. The first node receives acknowledgments indicating the respective sequence numbers of the transmitted cells that were received at the second node. Upon receiving an indication at the first node that a transmitted cell having a given sequence number was not properly received at the second node, the stored cells are retransmitted from the buffer starting from the cell with the given sequence number.

Abstract: A network interface adapter includes an outgoing packet generator, adapted to generate an outgoing request packet for delivery to a remote responder responsive to a request submitted by a host processor and a network output port, coupled to transmit the outgoing request packet over a network to the remote responder. A network input port receives an incoming response packet from the remote responder, in response to the outgoing request packet sent thereto, as well as an incoming request packet sent by a remote requester. An incoming packet processor receives and processes both the incoming response packet and the incoming request packet, and causes the outgoing packet generator, responsive to the incoming request packet, to generate, in addition to the outgoing request packet, an outgoing response packet for transmission to the remote requester.

Abstract: A network interface adapter includes a network interface and a client interface, for coupling to a client device so as to receive from the client device work requests to send messages over the network using a plurality of transport service instances. Message processing circuitry, coupled between the network interface and the client interface, includes an execution unit, which generates the messages in response to the work requests and passes the messages to the network interface to be sent over the network. A memory stores records of the messages that have been generated by the execution unit in respective lists according to the transport service instances with which the messages are associated. A completion unit receives the records from the memory and, responsive thereto, reports to the client device upon completion of the messages.

Abstract: A method of communication includes receiving, in a network interface device, first and second requests from an initiator process running on an initiator host to transmit, respectively, first and second data to first and second target processes running on one or more target nodes, via a packet network. A single dynamically-connected initiator context is allocated for serving both the first and second requests. A first connect packet referencing the dynamically-connected (DC) initiator context is directed to the first target process so as to open a first dynamic connection with the first target process, followed by transmission of the first data over the first dynamic connection. The first dynamic connection is closed after the transmission of the first data, and a second connect packet is transmitted so as to open a second dynamic connection with the second target process, followed by transmission of the second data.

Abstract: A method for communication includes routing a first packet, which belongs to a given packet flow, over a first routing path through a communication network. A second packet, which follows the first packet in the given packet flow, is routed using a time-bounded Adaptive Routing (AR) mode, by evaluating a time gap between the first and second packets, routing the second packet over the first routing path if the time gap does not exceed a predefined threshold, and, if the time gap exceeds the predefined threshold, selecting a second routing path through the communication network that is potentially different from the first routing path, and routing the second packet over the second routing path.

Abstract: A network interface adapter includes a network interface and a client interface, for coupling to a client device so as to receive from the client device work requests to send messages over the network using a plurality of transport service instances. Message processing circuitry, coupled between the network interface and the client interface, includes an execution unit, which generates the messages in response to the work requests and passes the messages to the network interface to be sent over the network. A memory stores records of the messages that have been generated by the execution unit in respective lists according to the transport service instances with which the messages are associated. A completion unit receives the records from the memory and, responsive thereto, reports to the client device upon completion of the messages.

Abstract: A method for controlling access by processes running on a host device to a communication network includes assigning to each of the processes a respective doorbell address on a network interface adapter that couples the host device to the network and allocating instances of a communication service on the network, to be provided via the adapter, to the processes. Upon receiving a request submitted by a given one of the processes to its respective doorbell address to access one of the allocated service instances, the adapter conveys the data over the network using the specified instance of the service, subject to verifying, based on the doorbell address to which the request was submitted, that the specified instance was allocated to the given process.