Abstract: A system is provided for synchronizing clocks. The system includes a plurality of devices in a network, each device having a local clock. The system is configured to synchronize the local clocks according to a primary spanning tree, where the primary spanning tree has a plurality of nodes connected through a plurality of primary links, each node of the plurality of nodes representing a respective device of the plurality of devices. The system is also configured to compute a backup spanning tree before a failure is detected in the primary spanning tree, wherein the backup spanning tree includes one or more backup links that are different from the primary links. As such, upon detection of a failure in the primary spanning tree, the system reconfigures the plurality of devices such that clock synchronization is performed according to the backup spanning tree.

Abstract: A communication protocol system is provided for reliable transport of packets. A content addressable memory hardware architecture including an acknowledgment coalescing module in communication with a content addressable memory (CAM). The acknowledgment coalescing module coalesces multiple acknowledgement packets as a single acknowledgement packet to reduce the overall numbers of the packet transmission in the communication protocol system. In addition, the acknowledgment coalescing module may also provide a piggyback mechanism to carry acknowledge information in a regular data packet. Thus, the need to generate a new acknowledgement packet may be eliminated. Accordingly, the network congestion and latency may be reduced, and the communication and transmission efficiency are enhanced.

Abstract: Systems and methods of offloading multicast virtual network packet processing to a network interface card are provided. In an example implementation, a network interface card can route packets in a virtual network. The network interface card can be configured to receive a data packet having a multicast header for transmission to a plurality of destination virtual machines. The network interface card can retrieve a list of next hop destinations for the data packet. The network interface card can replicate the packet for each next hop destination. The network interface card can encapsulate each replicated packet with a unicast header that includes a next hop destination virtual IP address indicating the next hop destination and a source virtual IP address, and transmit the encapsulated packets.

Abstract: A system is provided for synchronizing clocks. The system includes a plurality of devices in a network, each device having a local clock. The system is configured to synchronize the local clocks according to a primary spanning tree, where the primary spanning tree has a plurality of nodes connected through a plurality of primary links, each node of the plurality of nodes representing a respective device of the plurality of devices. The system is also configured to compute a backup spanning tree before a failure is detected in the primary spanning tree, wherein the backup spanning tree includes one or more backup links that are different from the primary links. As such, upon detection of a failure in the primary spanning tree, the system reconfigures the plurality of devices such that clock synchronization is performed according to the backup spanning tree.

Abstract: A communication protocol system is provided for reliable transport of packets. In this regard, an initiator entity may determine that outgoing data is to be transmitted to a target entity. The initiator entity may transmit, to the target entity, a solicited push request requesting the outgoing data to be placed at the target entity. In response to the solicited push request, the initiator entity may receive a push grant from the target entity. In response to the push grant, the initiator entity may transmit to the target entity the outgoing data to be placed at the target entity.

Abstract: Systems and methods of error handling in a network interface card (NIC) are provided. For a data packet destined for a local virtual machine (VM), if the NIC cannot determine a valid translation memory address for a virtual memory address in a buffer descriptor from a receive queue of the VM, the NIC can retrieve a backup buffer descriptor from a hypervisor queue, and store the packet in a host memory location indicated by an address in the backup buffer descriptor. For a transmission request from a local VM, if the NIC cannot determine a valid translated address for a virtual memory address in the packet descriptor from a transmit queue of the VM, the NIC can send a message to a hypervisor backup queue, and generate and transmit a data packet based on data in a memory page reallocated by the hypervisor.

Abstract: A network interface card with traffic shaping capabilities and methods of network traffic shaping with a network interface card are provided. The network interface card and method can shape traffic originating from one or more applications executing on a host network device. The applications can execute in a virtual machine or containerized computing environment. The network interface card and method can perform or include several traffic shaping mechanisms including, for example and without limitation, a delayed completion mechanism, a time-indexed data structure, a packet builder, and a memory manager.

Abstract: A communication protocol system is provided for reliable transport of packets. A content addressable memory hardware architecture including a reorder engine and a retransmission engine may be utilized for the reliable transport of the packets. In this regard, a reorder engine includes a content addressable memory (CAM) and one or more processors in communication with the CAM. The one or more processors are configured to receive a first set of data packets when executed by the one or more processors. The one or more processors are configured to access the content addressable memory to process the first set of data packets. The one or more processors are configured to save data information of the first set of the data packets in the content addressable memory.

Abstract: A network interface card with traffic shaping capabilities and methods of network traffic shaping with a network interface card are provided. The network interface card and method can shape traffic originating from one or more applications executing on a host network device. The applications can execute in a virtual machine or containerized computing environment. The network interface card and method can perform or include several traffic shaping mechanisms including, for example and without limitation, a delayed completion mechanism, a time-indexed data structure, a packet builder, and a memory manager.

Abstract: A flow table management system can include a hardware memory module communicatively coupled to a network interface card. The hardware memory module is configured to store a flow table including a plurality of network flow entries. The network interface card further includes a flow table age cache configured to store a set of recently active network flows and a flow table management module configured to manage a duration for which respective network flow entries in the flow table stored in the hardware memory module remain in the flow table using the flow table age cache. In some implementations, age information about each respective flow in the flow table is stored in the hardware memory module in an age state table that is separate from the flow table.

Abstract: A communication protocol system is provided for reliable transport of packets. A content addressable memory hardware architecture including a reorder engine and a retransmission engine may be utilized for the reliable transport of the packets. In this regard, a reorder engine includes a content addressable memory (CAM) and one or more processors in communication with the CAM. The one or more processors are configured to receive a first set of data packets when executed by the one or more processors. The one or more processors are configured to access the content addressable memory to process the first set of data packets. The one or more processors are configured to save data information of the first set of the data packets in the content addressable memory.

Abstract: Systems and methods of tracking page state changes are provided. An input/output is communicatively coupled to a host having a memory. The I/O device receives a command from the host to monitor page state changes in a region of the memory allocated to a process. The I/O device, bypassing a CPU of the host, modifies data stored in the region based on a request, for example, received from a client device via a computer network. The I/O device records the modification to a bitmap by setting a bit in the bitmap that corresponds to a location of the data in the memory. The I/O device transfers contents of the bitmap to the CPU, wherein the CPU completes the live migration by copying sections of the first region indicated by the bitmap to a second region of memory. In some implementations, the process can be a virtual machine, a user space application, or a container.

Abstract: A system includes a first processor configured to analyze packets received over a communication protocol system and determine one or more congestion indicators from the analysis of the data packets, the one or more congestion indicators being indicative of network congestion for data packets transmitted over a reliable transport protocol layer of the communication protocol system. The system also includes a rate update engine separate from the packet datapath and configured to operate a second processor to receive the determined one or more congestion indicators, determine one or more congestion control parameters for controlling transmission of data packets based on the received one or more congestion indicators, and output a congestion control result based on the determined one or more congestion control parameters.

Abstract: A flow table management system can include a hardware memory module communicatively coupled to a network interface card. The hardware memory module is configured to store a flow table including a plurality of network flow entries. The network interface card further includes a flow table age cache configured to store a set of recently active network flows and a flow table management module configured to manage a duration for which respective network flow entries in the flow table stored in the hardware memory module remain in the flow table using the flow table age cache. In some implementations, age information about each respective flow in the flow table is stored in the hardware memory module in an age state table that is separate from the flow table.

Abstract: Systems and methods of tracking page state changes are provided. An input/output is communicatively coupled to a host having a memory. The I/O device receives a command from the host to monitor page state changes in a region of the memory allocated to a process. The I/O device, bypassing a CPU of the host, modifies data stored in the region based on a request, for example, received from a client device via a computer network. The I/O device records the modification to a bitmap by setting a bit in the bitmap that corresponds to a location of the data in the memory. The I/O device transfers contents of the bitmap to the CPU, wherein the CPU completes the live migration by copying sections of the first region indicated by the bitmap to a second region of memory. In some implementations, the process can be a virtual machine, a user space application, or a container.

Abstract: A system is provided for synchronizing clocks. The system includes a plurality of devices in a network, each device having a local clock. The system is configured to synchronize the local clocks according to a primary spanning tree, where the primary spanning tree has a plurality of nodes connected through a plurality of primary links, each node of the plurality of nodes representing a respective device of the plurality of devices. The system is also configured to compute a backup spanning tree before a failure is detected in the primary spanning tree, wherein the backup spanning tree includes one or more backup links that are different from the primary links. As such, upon detection of a failure in the primary spanning tree, the system reconfigures the plurality of devices such that clock synchronization is performed according to the backup spanning tree.

Abstract: A communication protocol system is provided for reliable transport of packets. In this regard, an initiator entity may determine that outgoing data is to be transmitted to a target entity. The initiator entity may transmit, to the target entity, a solicited push request requesting the outgoing data to be placed at the target entity. In response to the solicited push request, the initiator entity may receive a push grant from the target entity. In response to the push grant, the initiator entity may transmit to the target entity the outgoing data to be placed at the target entity.

Abstract: Systems and methods of error handling in a network interface card (NIC) are provided. For a data packet destined for a local virtual machine (VM), if the NIC cannot determine a valid translation memory address for a virtual memory address in a buffer descriptor from a receive queue of the VM, the NIC can retrieve a backup buffer descriptor from a hypervisor queue, and store the packet in a host memory location indicated by an address in the backup buffer descriptor. For a transmission request from a local VM, if the NIC cannot determine a valid translated address for a virtual memory address in the packet descriptor from a transmit queue of the VM, the NIC can send a message to a hypervisor backup queue, and generate and transmit a data packet based on data in a memory page reallocated by the hypervisor.

Abstract: Systems and methods of offloading multicast virtual network packet processing to a network interface card are provided. In an example implementation, a network interface card can route packets in a virtual network. The network interface card can be configured to receive a data packet having a multicast header for transmission to a plurality of destination virtual machines. The network interface card can retrieve a list of next hop destinations for the data packet. The network interface card can replicate the packet for each next hop destination. The network interface card can encapsulate each replicated packet with a unicast header that includes a next hop destination virtual IP address indicating the next hop destination and a source virtual IP address, and transmit the encapsulated packets.

Abstract: Systems and methods of error handling in a network interface card (NIC) are provided. For a data packet destined for a local virtual machine (VM), if the NIC cannot determine a valid translation memory address for a virtual memory address in a buffer descriptor from a receive queue of the VM, the NIC can retrieve a backup buffer descriptor from a hypervisor queue, and store the packet in a host memory location indicated by an address in the backup buffer descriptor. For a transmission request from a local VM, if the NIC cannot determine a valid translated address for a virtual memory address in the packet descriptor from a transmit queue of the VM, the NIC can send a message to a hypervisor backup queue, and generate and transmit a data packet based on data in a memory page reallocated by the hypervisor.