Abstract: A method for all-to-all message exchange between program tasks including N>1 hierarchy levels ln, n=1 to N, in which a first level l1 includes a plurality of group tasks and each higher level l(n>1) includes at least one group of level l(n-1) groups to which that task belongs in respective hierarchy levels of the network topology; sending a message via the interconnection network to a respective destination task whose hierarchical identifier is determined; and using the hierarchical identifier to send the program task and the network topology, such that the resulting exchange pattern for the all-to-all message exchange exploits a hierarchical distance in the network topology in a desired manner.

Abstract: According to one embodiment, a method for handling congestion in a network includes determining that there is congestion on a first device in a network, setting a congestion indicator in a header of a packet to indicate an amount of congestion at the first device, sending the packet to all devices that send traffic to the first device, receiving the packet having the multi-bit indicator in a header thereof at a device that sends traffic to the first device, and reducing a congestion window by a factor of between about 5% and about 50% based on a severity of the congestion indicated by the multi-bit indicator, wherein the congestion window is reduced by a greater factor when the congestion is indicated as being more severe. Other systems and methods for handling congestion in a network are described according to more embodiments.

Abstract: Embodiments relate to creating a coherent load or congestion map that displays the simultaneous activity of all queues of physical and virtual switches and adapters in a network without forcing clock synchronization. An aspect includes sampling, by a central processing device, a status of all queues in a plurality of elements in a network. The sampled data flows are received from the plurality of elements in the network and an image is created of the network. The image includes the status of all sampled queues in the plurality of elements at a point in time. Accordingly, a load map is created without synchronizing clocks of the plurality of elements. The load map is assembled using segments of the image of the network.

Abstract: A reliability system for a Converged Enhanced Ethernet network may include a plurality of end points each comprising a layer 4 transport layer, where each end point is connected to a data center bridging (DCB) layer 2 network. The system may also include an adaptor between the layer 4 transport layer and the DCB layer 2 network to translate at least one of flow and congestion control feedback signals, provided by at least one of the DCB network and the transport layer, to consolidated feedback signals for controlling transmission by the transport layer.

Abstract: A method for all-to-all message exchange between program tasks including N>1 hierarchy levels ln, n=1 to N, in which a first level l1 includes a plurality of group tasks and each higher level l(n>1) includes at least one group of level l(n?1) groups to which that task belongs in respective hierarchy levels of the network topology; sending a message via the interconnection network to a respective destination task whose hierarchical identifier is determined; and using the hierarchical identifier to send the program task and the network topology, such that the resulting exchange pattern for the all-to-all message exchange exploits a hierarchical distance in the network topology in a desired manner.

Abstract: In one embodiment, a computer program product includes a computer readable storage medium having program instructions embodied therewith. The embodied program instructions are readable/executable by a processor to receive, by the processor, a packet via a network fabric, the network fabric having a plurality of interconnected fabric switches. The embodied program instructions are also readable/executable by the processor to determine, by the processor, a path through the network fabric by consulting a source-routing table. Moreover, the embodied program instructions are readable/executable by the processor to store, by the processor, source-routing information to a packet header for the packet, the source-routing information including the path. In addition, the embodied program instructions are readable/executable by the processor to send, by the processor, the packet according to an indication in the source-routing information.

Abstract: Methods and apparatus are provided for routing data packets between source and destination switches in a fat tree network. For each packet, a route is selected having three or less routing phases such that the route follows a shortest path across the network between the source and destination switches. The data packet is transmitted from the source switch to the destination switch, via the route, on one of first and second virtual channels unless the route includes a predetermined one of a down-up turn and an up-down turn. If the route includes the predetermined one of a down-up turn and an up-down turn, the data packet is transmitted, via the route, on the first virtual channel up to the switch 1 at which the turn occurs and on the second virtual channel from that switch. This provides full-connectivity in fat tree networks with deadlock free operation.

Abstract: In one embodiment, a system includes a network fabric having a plurality of fabric switches interconnected in the network fabric and a switch controller having logic adapted to configure the network fabric, determine one or more paths through the network fabric between any two hosts connected thereto, and create a source-routing table to store the one or more paths through the network fabric between any two hosts connected thereto. In another embodiment, a method includes receiving or creating a packet using a NIC of a host connected to a network fabric having a plurality of fabric switches interconnected therein, determining a path through the network fabric by consulting a source-routing table stored to the host, storing source-routing information to a packet header for the packet, the source-routing information including the path, and sending the packet to a first device or hop indicated by the path in the source-routing information.

Abstract: In one embodiment, a method includes receiving first overlay network traffic via a first input overlay tunnel at a multi-protocol virtual tunnel end point (VTEP) implemented in an accelerated network interface card (NIC) of a server. The method also includes routing the first overlay network traffic to a second overlay network tunnel which adheres to a second overlay network protocol in response to a determination that a destination of the first overlay network traffic is specified as the second overlay network tunnel. Moreover, the method includes receiving second overlay network traffic via the first input overlay tunnel at the multi-protocol VTEP. The method also includes bridging the second overlay network traffic to a first destination overlay network tunnel terminated at the multi-protocol VTEP in response to a determination that a destination of the second overlay network traffic is specified as the first destination overlay network tunnel.

Abstract: Embodiments relate to bypassing congestion points in a network. An aspect includes sampling queues of a plurality of switches in a network. When packet congestion is detected at a congestion point of a first switch, the packet flow contributing to the packet congestion is identified. A congestion notification message indicating the identified packet flow is then propagated to upstream switches, which are upstream from the first switch in the network. The congestion notification message is then snooped by the upstream switches. Virtual queues within the upstream switches are associated with the identified packet flow to hold packets associated with the identified packet flow. The packets associated with the identified packet flow are then re-routed to bypass the packet congestion in the first switch.

Abstract: In one embodiment, a method includes selecting a flow from a head of a first control queue or a second control queue. The method also includes providing service to the selected flow. Moreover, the method includes decreasing a service credit of the selected flow by an amount corresponding to an amount of service provided to the selected flow. In another embodiment, a computer program product includes a computer readable storage medium having program code embodied therewith. The embodied program code is readable/executable by a device to select, by the device, a flow from a head of a first control queue or a second control queue. The embodied program code is also readable/executable to provide, by the device, service to the selected flow, and decrease, by the device, a service credit of the selected flow by an amount corresponding to an amount of service provided to the selected flow.

Abstract: A network fabric may divide a physical connection into a plurality of VLANs as defined by IEEE 802.1Q. Moreover, many network fabrics use Priority Flow Control to identify and segregate network traffic based on different traffic classes or priorities. Current routing protocols define only eight traffic classes. In contrast, a network fabric may contain thousands of unique VLANs. When network congestion occurs, network devices (e.g., switches, bridges, routers, servers, etc.) can negotiate to pause the network traffic associated with one of the different traffic classes. Pausing the data packets associated with a single traffic class may also stop the data packets associated with thousands of VLANs. The embodiments disclosed herein permit a network fabric to individually pause VLANs rather than entire traffic classes.

Abstract: In one embodiment, a system includes a hardware processor and logic integrated with and/or executable by the processor. The logic is configured to classify a traffic flow into a traffic class based on at least one criteria related to the traffic flow and request that a credit manager remap flow credits corresponding to a first traffic class to flow credits corresponding to a second traffic class. In another embodiment, a method for providing credit-based flow control includes classifying a traffic flow into a traffic class based on at least one criteria related to the traffic flow, the traffic class being selected from a plurality of traffic classes. The method also includes storing an identifier indicating the traffic class of packets of the traffic flow according to a virtual local area network (VLAN) identifier in a three bit VLAN tag portion of a header of one or more of the packets.

Abstract: In one embodiment, a system includes processor; and logic integrated with and/or executable by the processor, the logic being adapted to: assign a VLAN type to each of a plurality of VLANs of an architecture; generate a VLAN list type-length-value (vTLV) message; and transmit information to resources based at least in part on the vTLV message, wherein the resources comprise at least one virtual switch and one or more of: at least one physical switch; at least one virtual port; at least one physical port; at least one virtual machine; at least one converged network adapter (CNA); and at least one fiber channel forwarder (FCF).

Abstract: Embodiments relate to proactively probing the packet queues of elements in a physical or virtual network to predict and prevent the occurrence of congestion points. An aspect includes receiving a first feedback request at a central controller connected to a plurality of switches in a network. The first feedback request includes a request to periodically probe a status of queues of switches in the network. A second feedback request is then transmitted to one or all the switches in a path leading to a designated destination. Responses to the second feedback request are received at the central controller from a designated proxy switch, which aggregated the responses into a single data packet. Accordingly, the responses extracted from the single data packet at the central controller are used to preventing future congestion points.

Abstract: Embodiments relate to proactively probing the packet queues of elements in a physical or virtual network to predict and prevent the occurrence of congestion points. An aspect includes receiving a first feedback request at a central controller connected to a plurality of switches in a network. The first feedback request includes a request to periodically probe a status of queues of switches in the network. A second feedback request is then transmitted to one or all the switches in a path leading to a designated destination. Responses to the second feedback request are received at the central controller from a designated proxy switch, which aggregated the responses into a single data packet. Accordingly, the responses extracted from the single data packet at the central controller are used to preventing future congestion points.

Abstract: In one embodiment, a system includes a processor and logic integrated with and/or executable by the processor, the logic being adapted to: receive a plurality of flows, each flow comprising packets of data, assign a service credit to each of the plurality of flows, assign a weight parameter to each of the plurality of flows, select a flow from a head of a first control queue unless the first control queue is empty or there is indication that the first control queue should be avoided, wherein a flow is selected from a head of a second control queue when the first control queue is empty or there is indication that the first control queue should be avoided, provide a number of units of service to the selected flow, and decrease the selected flow's service credit by an amount corresponding to the number of units of service provided thereto.

Abstract: In one embodiment, a method for providing multi-protocol overlay handling includes receiving first traffic via an input overlay tunnel at a multi-protocol virtual tunnel end point (VTEP)-enabled device, the first traffic including a plurality of overlay-encapsulated packets which adhere to a first overlay network protocol, and wherein the input overlay tunnel adheres to the first overlay network protocol; routing the first traffic to a second overlay network tunnel which adheres to a second overlay network protocol when a destination of the first traffic is specified as the second overlay network tunnel, the second overlay network tunnel being terminated at the multi-protocol VTEP-enabled device; and bridging the first traffic to a destination overlay network tunnel terminated at the multi-protocol VTEP-enabled device when the destination of the first traffic is specified as the destination overlay network tunnel, the destination overlay network tunnel being terminated at the multi-protocol VTEP-enabled devic

Abstract: Embodiments relate to bypassing congestion points in a network. An aspect includes sampling queues of a plurality of switches in a network. When packet congestion is detected at a congestion point of a first switch, the packet flow contributing to the packet congestion is identified. A congestion notification message indicating the identified packet flow is then propagated to upstream switches, which are upstream from the first switch in the network. The congestion notification message is then snooped by the upstream switches. Virtual queues within the upstream switches are associated with the identified packet flow to hold packets associated with the identified packet flow. The packets associated with the identified packet flow are then re-routed to bypass the packet congestion in the first switch.

Abstract: A virtual network is implemented on a physical network. A virtual network data packet is tunneled through the physical network via encapsulation within a physical network data packet and via transmission of the physical network data packet through the physical network. A network congestion notification capability of the virtual network is preserved and modified during transmission of virtual network data through the physical network and vice-versa. Congestion notification metadata can be copied from a header of a virtual network data packet to a header of a physical network data packet when the virtual network data packet is encapsulated into the physical network data packet. Congestion notification metadata can be copied from a header of a physical network data packet to a header of a virtual network data packet when the virtual network data packet is decapsulated from the physical network data packet.